Title of Invention	NOVEL PIPERIDINES
Abstract	A process for producing crystalline form I of cabergoline, which process comprises crystallization of the desired form from a toluene/diethyl ether mixture comprising raw cabergoline, followed by recovery and drying of the resulting crystals. A new solvate form V of cabergoline, useful as an intermediate, is also provided.

Full Text

The present invention is concerned with novel piperidine derivatives, their manufacture and use as medicaments. In particular, the invention is concerned with the novel piperidine derivatives of general formula I wherein R1 represents aryl or heterocyclyl; R2 represents phenyl, naphthyl, acenaphthyl, cyclohexyl, pyridyl, pyrimidinyl, pyrazinyl, oxo-pyridinyl, diazinyl, triazolyl, thienyl, oxazolyl, oxadiazolyl, thiazolyl, pyrrolyl or furyl, which groups can be substituted by 1-3 halogen, hydroxy, cyano, trifluoromethyl, lower-alkyi, halo-lower-alkyi, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyi, cyano-lower-alkyi, carboxy-lower-alkyl, lower-alkanoyloxy-lower-alkyi, lower-alkoxy-carbonyloxy-lower-alkyl, lower-alkoxycarbonyl, or lower-alkoxy groups, or by lower-alkylenedioxy, and/or by a group Li-T1-L2- T2.L3-T3-L4-T4-L5-U; L1, L2, L3, L4 and L5 independently of one another represent a bond, C1-8-alkylene, C2-8-alkenylene or C2-8-alkylene or are absent; T1, T2, T3 and T4 independently of one another represent (a) a bond or are absent or represent one of the groups (b) -CH(OH)- (c) -CH(0R6)- (d) -CH(NR5R6)- (e) -CO-Grn/So 30.7.96 (f) -CR7R8- (g) -O- or -NR6- (h) -S(0)o-2 -(i) -SO2NR6 - (j) -NR6 SO2- (k) -CONR6 - (I) -NR6 co- Cm) -O-CO- (n) -CO-O- (0) -O-CO-O- (p) -O-CO-NR6- (q) -NR6 -CO-NR6- (r) -NR6 -CO-O- and the bonds emanating from (b), (d), (e) and (g)-(r) join to a C atom of the adjacent group and this C atom is saturated when the bond emanates from a hetero atom, and not more than two groups (b)-(f), three groups (g)-(h) and one group (i)-(p) are present; R3 represents hydrogen, hydroxy, lower-alkoxy or lower-alkenyloxy; and R4 represents hydrogen, lower-alkyl, lower-alkenyl, lower-alkoxy, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyl, benzyl, 0x0 or a group R4a-z1-X1- in which RA represents (a)H- (b) lower-alkyl- (c) lower-alkenyl- (d) hydroxy-lower-alkyl- (e) polyhydroxy-lower-alkyl- (f) lower-alkyl-O-lower-alkyl- (g) aryl- (h) heterocyclyl-(i) arylalkyl-(j) heterocyclylalkyl-(k) aryloxyalkyl- (1) heterocyclyloxylalkyl- (m) (R5R6)-N-(CH2)0-2-(n) (R5R6)-N- (O) lower-all (p) aryi-S(O)0-2- (q) heterocyclyl-S(O)0-2-(r) HO-SO3- or salt thereof (s) H2N-C(NH)-NH- (t) NC-, and the bonds emanating from (n)-(t) join to a C atom of the adjacent group and this C atom is saturated when the bond emanates from a hetero atom; Z represents (a) a bond, is absent or represents one of the groups (b) lower-alkylene- (c) lower-alkenylene- (d) -O-,-N(Ril)-,-S(O)0-2- (e) -CO- (f) -O-CO- (g) -O-CO-O- (h) -O-CO-N(R1)-, (i) -N(R11)-CO-O-G) -CO-NCRll)-(k) -N(R11)-CO- (1) -N(R11)-CO-N(R11)- (m) -CH(0R9)-, and the bonds emanating from (d) and (f)-(m) join to a C atom of the adjacent group and this C atom is saturated when the bond emanates from a hetero atom; Xi represents (a) a bond, is absent or represents one of the groups (b) -O- (c) -N(R11)-, (d) -S(O))0-2- (e) -(CH2)i.3- or R3 and R4 together represent a bond; R5 and R6 represent hydrogen, lower-all R7 and R8 together with the C atom to which they are attached represent a 3-7 membered ring which can contain one or two 0 or S atoms or SO or SO2 groups; R9 represents hydrogen, lower-alkyl, acyl or arylalkyl; R10 represents carboxyalkyl, alkoxycarbonylalkyl, alkyl or hydrogen; R11 represents hydrogen or lower-alkyl; U represents hydrogen, lower-alkyl, cycloalkyl, cyano, optionally substituted cycloalkyl, aryl or heterocyclyl; Q represents ethylene or is absent; X represents a bond, oxygen, sulphur or a group -CH-R''-, -CHOR9-, -O-CO, -CO- or C=NORT0-with the bond emanating from an oxygen or sulphur atom joining to a saturated C atom of group Z or to Rl; W represents oxygen or sulphur; Z represents lower-alkylene, lower-alkenylene, hydroxy-lower-alkylidene, -O-, -S-, -O-Alk-, -S-Alk-, -Alk-O- or -Alk-S-, in which Alk represents lower alkylene; provided that a) X is -CH-RT'- and either R2 contains a substituent L1-T1-T2-L3.T3-L4-T4-L5.U or R4 IS a substituent defined above other than hydrogen when Z represents -O- or -S-; b) X is -CH-R11- when Z represents -O-Alk- or -S-Alk-; and c) Z represents lower-alkenylene, -Alk-O- or -Alk-S- when X represents a bond; n is 1 or, when X represents -O-CO-, 0 or 1; and m is 0 or 1; and pharmaceutically usable salts thereof; with the exception of the compound 4-(4-fluorophenyl)-3-(3,4-methylenedioxybenzyloxy)piperidine and its hydrochloride. The term "lower" used here denotes groups with 1 -6, preferably 1-4, C atoms. Examples of lower alkyl and alkoxy groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl and, respectively, methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec.-butoxy and tert-butoxy. Lower-alkylenedioxy groups are preferably methylenedioxy, ethylenedioxy and propylenedioxy. Acetyl, propionyl and butyryl are examples of lower-alkanoyi groups, Cycloalkyl signifies a saturated, cyclic hydrocarbon group with 3-6 carbon atoms, i.e. cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl. C1-8-Alkylene groups are e.g. methylene, ethylene, propylene, 2-methyl-propylene, tetra-, penta- and hexamethylene; C2-8-alkenylene groups are e.g. vinylene and propenylene; C2-8-alkynylene groups are e.g. ethynylene. Acyl groups are alkanoyl groups, preferably lower-alkanoyi groups, or aroyI groups such as benzoyl. Aryl denotes mono-nuclear or poly-nuclear aromatic groups which can carry one or more substituents, such as, for example, phenyl, substituted phenyl, naphthyl, substituted naphthyl, tetrahydronaphthyl or substituted tetrahydronaphthyl. Examples of substitutents on such aryl groups are lower-alkyl, trifluoromethyl, nitro, amino, lower-alkenyl, lower-alkoxy, lower-alkylcarbonyloxy, hydroxy, halogen, cyano, carbamoyl and lower-alkylenedioxy, as well as optionally halo-, lower-alkyl-, lower-alkoxy- or dihydroxy-lower-alkylaminocarbonyl- substituted phenyl, phenoxy, phenylthio, phenyl-lower-alkyl or phenyl-lower-alkoxy. Further examples of substituents on aryl groups are lower-alkoxycarbonylphenyl, hydroxy-lower-alkyl-phenyl, benzyloxy, pyridylcarbonylamino-lower-alkyl, lower-alkenyloxy, lower-alkoxy-lower-alkoxy, methoxybenzyloxy, hydroxybenzyloxy, phenethyloxy, methylenedioxybenzyloxy, dioxolanyl-lower-alkoxy, cyclopropyl-lower-alkoxy, hydroxy-lower-alkoxy, carbamoyloxy-lower-alkoxy, pyridyl-carbamoyl-oxy-lower-alkoxy, benzoyloxy-lower-alkoxy; as well as optionally halo-, lower-alkyl-, lower-alkoxy- or dihydroxy-lower-alkylaminocarbonyl-substituted pyridyl, pyridyloxy, pyridylthio, pyridylamino, pyridyl-lower-alkyl, pyridyl-lower-alkoxy, pyrimidinyl, pyrimidinyloxy, pyrimidinylthio, pyrimidinylamino, pyrimidinyl-lower-alkyl, pyrimidinyl-lower-alkoxy, thienyl, thienyl-lower-alkyl, thienyl-lower-alkoxy, furyl, furyl-lower-alkyl and furyl-lower-alkoxy. The term heterocyclyl denotes monocyclic or bicyclic, saturated and unsaturated heterocyclic groups with 1 to 4 nitrogen atoms and/or 1 or 2 sulphur or oxygen atoms, which can be mono- or multiply-substituted, especially by (in the case of unsaturated heterocyclyl groups) alkyl, hydroxy, alkoxy, nitro or halogen or by substituents as defined above for aryl groups or (in the case of saturated heterocyclyl groups) by alkyl or alkoxy. Examples of heterocyclyl groups are pyridyl, thienyl, pyrazinyl, triazolyl, imidazolyl, benzthiazolyl, furyl, pyrimidinyl, morpholinyl, quinazolinyl, quinolyl, quinoxalinyl, isoquinolyl, benzo[b]thienyl, isobenzofuranyl, benzimidazolyl, 2-oxo-benzimidazolyl or thiazolyl. Examples of substituted heterocyclyl groups are nitrobenzthiazolyl, phenyl-tetrazolyl,phenyl-oxadiazolyl, phenyl-oxadiazolyl, thienyl-oxadiazolyl, furanyl-oxadiazolyl, benzyl-oxadiazolyl and phenyl-oxazolyl. Examples of saturated heterocyclyl groups are dioxolanyl, dioxanyl, dithiolanyl, dithianyl, pyrrolidinyl, piperidinyl, piperazinyl, 4-methylpiperazinyl, morpholinyl, thiomorpholinyl, 2-hydroxymethylpyrrolidinyl, 3-hydroxy-pyrrolidinyl, 3,4-dihydroxypyrrolidinyl, 4-hydroxypiperidinyl, 4-oxopiperidinyl, 3,5-dimethylmorpholinyl, 4,4-dioxothio- morpholinyl, 4-oxothiomorpholinyl, 2,6-dimethylmorpholinyl, Z-oxc-imidazolidinyl, 2-oxo-oxazolidinyl, 2-oxo-pyrrolidinyl, 2-oxo-[1,3]oxazinyl, 2-oxo-tetrahydro-pyrimidinyl and the like. In the case of R1, R4a and R9 the aryl, aroyi and heterocyclyl groups can be additionally substituted by heterocyclylalkyl, heterocyclylalkoxy or heterocyclylalkoxyalkyl, such as, for example, piperidinoalkyl, piperidinoaikoxy, piperidinoalkoxyalkyl, morpholinoalkyl, morpholinoalkoxy, morpholinoalkoxyalkyl, piperazinoalkyl, piperazinoalkoxy, piperazinoalkoxyalkyl or N-methylpiperazinoalkyl, N-methylpiperazinoalkoxy, N-methyl-piperazinoalkoxyalkyl, as well as alkylaminoalkyl, alkylamino-alkoxy, alkylamino-alkoxyalkyl, mono- and polyhydroxy-alkyl, -alkoxy, -alkoxyalkyl and -alkoxyalkoxy, carbamoylalkyloxy, lower-alkoxy, amino-lower-alkoxy, hydroxy-lower-alkoxy or by the -O-CH2CH(OH)CH2NRx group, in which NRx represents a mono-or di-lower-alkyl-amino, piperidino, morpholino, piperazino or N-methylpiperazino group. Examples of 5- and 6-membered heterocyclic rings denoted by NR5R6 are pyrrolidinyl, piperidinyl, piperazinyl, morpholinyl, thiomorpholinyl, 2-hydroxymethyl-pyrrolidinyl, 3-hydroxypyrrolidinyl, 3,4-dihydroxypyrrolidinyl, 4-hydroxypiperidinyl, 4-oxopiperidinyl, 3,5-dimethylmorpholinyl, 4,4-dioxothiomorpholinyl, 4-oxothiomorpholinyl, 2,6-dimethyl¬morpholinyl, 2-oxo-imidazolidinyl, 2-oxo-oxazolidinyl, 2-oxo-pyrrolidinyl, 2-oxo-[1,3]oxazinyl, 2-oxo-tetrahydro-pyrimidinyl and the like. Cyclopentyl, cyclohexyl, cycloheptyl, 1,3-dioxolanyl, 1,3-dioxanyl, 1,3-dithiolanyl and 1,3-dithianyl are examples of 3-7 membered rings denoted by CR7R8. The term polyhydroxy-alkyl denotes C1-C7-alkyl groups which can be substituted by 2-6 hydroxy groups, such as e.g. glyceryl, arabityl, sorbityl etc. The compounds of formula I have at least two asymmetric carbon atoms and can accordingly exist in the form of optically pure diastereomers, diastereomer mixtures, diastereomeric racemates or mixtures of diastereomeric racemates. The invention embraces all of these forms. Diastereomeric mixtures, diastereomeric racemates or mixtures of diastereomeric racemates can be separated according to usual methods, e.g. by column chromatography, thin-layer chromatography, HPLC and the like. Preferred compounds in accordance with the invention are those of the general formula wherein R1-R4, Q, W, X, Z, n and m have the significance given above. A further preferred group of compounds of formula I comprises compounds of the formula wherein R1 represents aryl or heterocyclyl; R2 represents phenyl, cyclohexyl, phenyl or cyclohexyl substituted by halogen, hydroxy, cyano, trifluoromethyl, lower-alkyl, halo-lower-alkyl, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyl, cyano-lower-alkyl, carboxy-lower-alkyl, lower-alkanoyloxy-lower-alkyl, lower-alkoxycarbonyloxy-lower-alkyl, lower-alkoxycarbonyl, lower-alkoxy or lower-alkylenedioxy or by a group L1-TT-L2-T2-L3-T3-L4-T4-L5-U; or naphthyl or acenaphthyl; L1, L2, L3, L4 and L5 independently of one another represent a bond, C1 -8-alkylene, C2-8-alkenylene or C2-8-alkynylene or are absent; T1, T2, T3 and T4 independently of one another represent (a) a bond or are absent or represent one of the groups (b) -CH(OH)- (c) -CH(0R6)- (d) -CH(NR5R6)- (e) -CO- (f) -CR7R8- (g) -O- or -NR6-, (h) -S(O)0-2-(i) -SO2NR6 - G) -NR6 SO2-(! with the bonds emanating from (b), (d), (e) and (g)-(p) joining to a C atom of the adjacent group and this C atom being saturated when the bond emanates from a hetero atom, and not more than two groups (b)-(f), three groups (g)-(h) and one group (i)-(p) being present; R3 represents hydrogen, hydroxy, lower-alkoxy or lower-all R4 represents hydrogen, lower-alkyl, lower-alkenyl, lower-alkoxy, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyl or benzyl; R5 and R6 are hydrogen, lower-alkyl or acyl or together with the N atom to which they are attached represent a 5- or 6-membered heterocyclic ring which can contain an additional N atom or an 0 or S atom; R7' and R8 together with the C atom to which they are attached represent a 3-7 membered ring which can contain one or two oxygen or sulphur atoms; U represents hydrogen, lower-alkyl, cycloalkyl, cyano, aryl or heterocyclyl; Q represents ethylene or is absent; X represents oxygen, sulphur or a group -CH2-, -CHOR9- or -OCO-and R9 represents hydrogen, lower-alkyl, acyl or arylalkyl; W is absent; or can represent oxygen or sulphur when R3 represents hydrogen; and Z represents lower-alkylene or is absent; and pharmaceutically usable salts thereof; with the exception of the compound 4-(4-fluorophenyl)-3-(3,4-methylenedioxybenzyloxy)piperidine and its hydrochloride. Furthermore, compounds of formulae I and lA in which W is absent and those in which Q is absent are preferred. X is preferably oxygen, sulphur or -CO-; Z is preferably methylene. Preferred groups R"" are phenyl and phenyl substituted by lower-alkyl, lower-alkenyl, lower-alkoxy, lower-alkylthio, halogen, hydroxy, hydroxy-lower-alkoxy, lower-alkoxy-lower-alkoxy, lower-alkylsulphinyl, lower-alkylsulphonyl, cyano, trifluoromethyl, trifluoromethoxy, carboxy, cyclobutylmethoxy-lower-alkyl, lower-alkylenedioxy, phenyl, phenoxy, lower-alkoxycarbonylphenyl, hydroxy-lower-alkylphenyl, 2,3-dihydroxy propylaminocarbonylphenyl, benzyloxy, benzoyl, pyridyl-lower-alkoxy-lower-alkyl or nicotinoylamino-lower-alkyl. Other preferred groups R1 are naphthyl, naphthyl substituted by hydroxy, oxo, lower-alkoxy, lower-alkenyloxy, lower-alkoxy-lower-alkoxy, di-lower-alkylamino, 2,3-dihydroxypropoxy, 2,3-dihydroxypropoxy-lower-alkoxy, 2,3-dimethoxypropoxy, lower-alkoxycarbonyl-lower-alkoxy, carbamoyl-lower-alkoxy, methoxybenzyloxy, hydroxybenzyloxy, phenethyloxy, methylenedioxybenzyloxy, dioxolanyl-lower-alkoxy, cyclopropyl-lower-alkoxy, hydroxy-lower-alkoxy, carbamoyloxy-lower-alkoxy, pyridyl-carbamoyloxy-lower-alkoxy, morpholino-lower-alkoxy, 3-morpholJn0-2-hydroxypropoxy, N-methyl-piperazino-N-lower-alkoxy, benzoyloxy-lower-alkoxy or picolyloxy; tetrahydronaphthyl or methyl-substituted tetrahydronaphthyl, or indanyl. Likewise preferred groups R1 are pyridyl, benzimidazolyl, di-lower-alkoxypyrimidinyl or 2- and 5-benzo[b]thienyl, 6- and 7-quinolyl, 6- and 7-isoquinolyl, 6- and 7-tetrahydroquinolyl, 6-and 7-tetrahydroisoquinolinyl, 6-quinoxalinyl, 6- and 7-quinazo¬linyl, as well as 6- and 7-quinolyl, 6- and 7-isoquinolyl, 6- and 7-tetrahydroquinolyl, 6- and 7-tetrahydroisoquinolyl, 6-quinoxa¬linyl or 6- and 7-quinazolinyl substituted by hydroxy, oxo, lower-alkoxy, lower-aikenyloxy, lower-alkoxy-lower-alkoxy, di-lower-alkylamino, 2,3-dihydroxypropoxy, 2,3-dihydroxypropoxy-lower-alkoxy, 2,3-dimethoxypropoxy, lower-alkoxycarbonyl-lower-alkoxy, carbamoyl-lower-alkoxy, methoxybenzyloxy, hydroxybenzyloxy, phenethyloxy, methylenedioxybenzyloxy, dioxolanyl-lower-alkoxy, cyclopropyl-lower-alkoxy, hydroxy-lower-alkoxy, carbamoyloxy-lower-alkoxy, pyridyl-carbamoyl-oxy-lower-alkoxy, morpholino-lower-alkoxy, 3-morphoIin0-2-hydroxypropoxy, N-methylpiperazino-N-lower-alkoxy, benzoyloxy-lower-alkoxy or picolyloxy. Preferred groups R2 are phenyl and phenyl substituted by halogen, hydroxy, cyano, trifluoromethyl, lower-alkyl, halo-lower-alkyl, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyl, cyano-lower-alkyl, carboxy-lower-alkyl, lower-alkanoyloxy-lower-alkyl, lower-alkoxycarbonyloxy-lower-alkyl, lower-alkoxycarbonyi, lower-alkoxy or lower-alkylenedioxy. Likewise preferred groups R2 are phenyl substituted by a group L1-T1-L2-T2-L3-T3-L4-T4-L5-U in which Ll and L2 are preferably absent or are C1-8-alkylene and L3is absent and U represents hydrogen, lower-alkyl, cyclo-lower-alkyl, phenyl, phenyl substituted by lower-alkyl, lower-alkoxy, lower-alkylthio, lower-alkylsulphinyl, lower-alkylenedioxy, halogen, benzoyl-lower-alkyl, halo-lower-alkyl, lower-alkanoyloxy or hydroxy; or naphthyl; or pyridyl, thienyl, pyrazinyl, triazolyl, imidazolyl, phenyl-oxadiazolyl, thienyl-oxadiazolyl, furyl-oxadiazolyl, phenyl-oxazolyl, benzthiazolyl, furyl, pyrimidinyl, nitrobenz-thiazolyl, phenyltetrazolyl or morpholinyl. In groups T1-T4 the meanings (a)-(c), (e)-(h), (m) and (n) are preferred. Examples of especially preferred groups R2 are phenyl or phenyl substituted by 2-benzothiazolyl-thio-lower-alkyl, 2-benzyloxy-3-methoxypropoxy, 2-benzoyloxy-3-methoxypropoxy, 2,3-dihydroxypropoxy, 2-hydroxy-3-benzylamino-propoxy, 2-hydroxy-3-phenoxypropoxy, 2-hydroxy-3-phenylthiopropoxy, 2-methoxy-3-phenoxypropoxy, 2-methoxy-3-benzyloxypropoxy, 2-methyl-3-fluoro-phenylbutyryloxy-lower-alkoxy, 2-lower-alkenyloxy-4-phenylbutyl, 3,4,5-trimethoxyphenyl-oxadiazolyl-lower-alkoxy, 6-nitr0-2-benzothiazolyl-thio-lower-alkyl, benzamido-lower-alkoxy, benzamido-lower-alkyl, benzoyl-lower-alkoxy and ketals thereof, benzoyl-lower-alkyl and ketals thereof, benzoyl-lower-alkyl-aminocarbonyl-lower-alkyl, benzoyl-lower-alkoxycarbonyl-lower-alkyl, benzoyl-lower-alkylaminocarbonyl, benzoyloxy, benzoyloxy-lower-alkyl-benzoyloxy-lower-alkoxy, benzoyloxy-lower-alkoxy, benzoyloxy-lower-alkyl, benzthiazolylthio-lower-alkoxy, benzthiazolylthio-lower-alkyl, benzylcarbamoyl-lower-alkoxy, benzyloxy-lower alkylcarbonyloxy-lower-alkyl, benzyloxy-lower-alkoxy, benzylthio-lower-alkoxy, carbamoyloxy-lower-alkoxy, carbamoyloxy-lower-alkyl, carboxy-lower-alkoxy, carboxy-lower-alkyl, cyano, cyano-lower-aikoxy, cyano-lower-alkyl, cyanophenyl-lower-alkoxy, cyclohexylcarbonyloxy-lower-alkyl, cyclopropylcarbonyloxy-lower-alkyl, cyclopropyloxy-benzyloxy-lower-alkoxy, dioxolanyl-lower-alkoxy, furyl-oxadiazolyl-lower-alkoxy, furoyloxy-lower-alkoxy, halo-phenoxy-lower-alkyl, halobenzoyl-lower-alkoxy, halobenzoyloxy-lower-alkyl, halobenzoyloxy-lower-alkoxy, halobenzyloxy-lower-alkoxy, halogen, halogen-lower-alky I, halophenoxy, halophenyl-oxadiazolyl-lower-alkoxy, hydroxy, hydroxy-benzoyloxy-lower-alkyl, hydroxy-benzyloxy-lower-alkoxy, hydroxy-lower-alkoxy, hydroxy-lower-alkyl, imidazolylcarbonyloxy-lower-alkyl, methoxybenzoyl-lower-alkyl, methoxybenzyloxy-lower-alkoxy, methylenedioxybenzoyl-lower-alkoxy, morpholino-lower-alkoxy, morpholinocarbonyioxy-lower-alkoxy, morpholinocarbonyloxy-lower-alkyl, N-methylaminophenyl-carbonyloxy-lower-alkyl, N-methyl-benzylamino-lower-alkoxy, N-methylpyrrolylcarbonyloxy-lower-alkoxy, N-lower-alkylbenzamido-lower-alkyl, naphthyl-lower-alkoxy, nicotinoyloxy-lower-alkoxy, nicotinoyloxy-lower-alkyl, lower-alkanoylbenzoyloxy-lower-alkyl, lower-alkanoyloxy-lower-alkoxy lower-alkanoyioxy-lower-alkyl, lower-alkenyl-benzyloxy-lower-alkoxy, lower-alkenyloxy, lower-alkenyloxy-benzyloxy-lower-alkoxy, lower-alkoxy, lower-alkoxy-benzoyloxy-lower-alkyl, lower-alkoxy-carbonyl, lower-alkoxy-lower-alkyl, lower-alkoxybenzoylamino-lower-alkyl, lower-alkoxy benzylcarbonyloxy-lower-alkyl, lower-alkoxy-benzyloxy-lower-alkoxy, lower-alkoxy-benzylthio-lower-alkoxy, lower-alkoxycarbonyl, lower-alkoxycarbonyl-lower-alkoxy, lower-alkoxycarbonyl-lower-alkyl, lower-alkoxyphenyl-oxadiazolyl-lower-alkoxy, lower-alkyl, lower-alky Ibenzyloxy-lower-alkoxy, lower-alky lenedioxy, lower-alky lenedioxybenzyloxy-lower-alkoxy, lower-alky Isulphonylbenzoyl-lower-alkoxy, lower-alkylthiobenzoyloxy-lower-alkoxy, lower-alky lthio-benzyloxy-lower-alkoxy benzoyloxybenzyl-lower-alkoxy, hydroxybenzyl-lower-alkoxy, lower-alkoxybenzyl-lower-alkoxy, lower-alkoxybenzylcarbonyloxy-alkoxy, phenoxy-benzyloxy-lower-alkoxy, phenoxycarbonyl-lower-alkyl, phenoxy-lower-alkenyloxy, phenoxy-lower-alkynyloxy, phenyl-lower-alkanoylamino-lower-alkyl, phenyl-lower-alkenyloxy, phenyl-lower-alkoxy, phenoxy-lower-alkyl, phenyl-lower-alkylamlnocarbonyl, phenoxy-lower-alkylcarbonyi-lower-alkoxy, phenyl-lower-alkylaminocarbonyl-lower-alkyl, phenylaminocarbonyloxy-lower-alkoxy, phenylaminocarbonyloxy-lower-alkyl, phenyl-hydroxy-lower-alkyl, phenyl-oxadiazolyl-lower-alkoxy phenyl-oxadiazolyl-lower-alkoxy, phenyl-oxadiazolyl-lower-alkyl, phenyl-oxazolyl-lower-alkoxy, phenyloxy-lower-alkoxy, phenylsulphamoyl-lower-alkyl, phenylsulphinyl-lower-alkyl, phenylsulphonyl-lower-alkoxy, phenylsulphonyl-lower-alkyl, phenyltetrazolyl-thio-lower-alkyl, phenylthio-lower-alkoxy, phenylthio-lower-alkyl, pyrazinylcarbonyloxy-lower-alkyl, pyridylaminocarbonyloxy-lower-alkoxy pyridylaminocarbonyloxy-lower-alkyl, pyridylcarbamoyloxy, pyridyl-lower-alkoxy-lower-alkoxy, pyridyl-lower-alkoxy-lower-alkyl, pyridyl-oxadiazolyl-lower-alkoxy, pyridylthio-lower-alkyl, pyrimidinyloxy-lower-alkoxy, pyrimidinylthio-lower-alkyl, thenoyloxy-lower-alkoxy, thenoyloxy-lower-alkyl, thienyl-oxadiazolyl-lower-alkoxy, triazolyl-lower-alkoxy, trifluoromethylbenzyloxy-lower-alkoxy or trifluoromethyl. Preferred groups R4 are 2-oxo-imidazolidin-l-yl-lower-alkyl, 4-hydroxy-piperidin-1-yl-lower-alkoxy, 4-hydroxy-piperidin-1 -yl-lower-alkoxy-lower-alkyl, 4-methyl-piperazin-1 -yl-lower-alkoxy, 4-methyl-piperazin-1 -yl-lower-alkoxy-lower-alkyl, 4-methyl-piperazin-1-yl-lower-alkyl-carbamoyloxy-lower- alkyl, 1,2,4-triazolyl-lower-alkyl, amino, amino-lower-alkyl, amino-lower-alkyl-amino ami no-lower-alky l-amino-lower-alky I, amino-lower-alkoxy, amino-lower-alkoxy-lower-alkyl, aminocarbonyloxy-lower-alkyl, benzyloxy or benzyloxy substituted by lower-alkyl, lower- alkenyl, lower-alkoxy, trifluoromethoxy, lower-alkylthio, hydroxy or halogen, benzyloxy-lower-alkyl or benzyloxy-lower-alkyl substituted by lower-alkyl, lower-alkenyl, lower-alkoxy or halogen, carbamoyloxy-lower-alkyl, cyano-lower-alkyl, di-lower-alkyl-amino, di-lower-a Iky l-amino-lower-alky I, di-lower-alkyl-amino-lower-alkyl-(N-lower-alkyl)-amino- lower-alkyl. di-lower-alkyl-amino-lower-alkyl-amino di-lower-alkyl-amino-lower-alkyl-amino-lower-alkyl, di-lower-alkyl-amino-lower-alkoxy di-lower-alkyl-amino-lower-alkoxy-lower-alkyl, dihydroxy-lower-alkoxy, dihydroxy-lower-alkoxy-lower-alkyl dihydroxy-lower-alkyl-amino, dihydroxy-lower-alkyl-amino-lower-alkyl guanidinyl-lower-alkoxy-lower-alkyl, guanidinyl-lower-aikyi, hydroxy, hydroxy-lower-alkyl, sulpiiooxy-lower-alkyl, hydroxy-lower-alkoxy, hydroxy-lower-alkoxy-lower-alkyl, morpholin-4-yl-lower-alkoxy, morpholin-4-yl-lower-alkoxy-lower-alkyl, morpholin-4-yl-lower-alkyl-carbamoyloxy-lower-alkyl, naphthyl-alkoxy or naphthyl-alkoxy substituted by lower-alkoxy, ower-alkoxy, ower-alkoxy-lower-alkoxy ower-alkoxy-lower-alkoxy-lower-alkyl, ower-alkoxy-lower-alkyl, ower-alkyl, lower-alky Isulphonylamino-lower-alky I, phenoxy-lower-alkyl or phenoxy-lower-alkyl substiuted by lower-alkyl, lower-alkoxy, phenyl-thio-lower-alkyl or phenyl-thio-lower-alkyl substituted by lower-alkyl, lower-alkoxy, piperazin-4-yl-lower-alkoxy, piperazin-4-yl-lower-alkoxy-lower-alkyl, piperidin-1 -yl-lower-alkyl-carbamoyloxy-lower-alkyl, piperidin-4-yl-lower-alkoxy, piperidin-4-yl-lower-alkoxy-lower-alkyl, pyridyl-lower-alkoxy, pyridyl-lower-alkoxy-alkyl, pyridylthio-lower-alkyl, pyrimidinyioxy-lower-alkyl or pyrimidinyloxy-lower-alkyl substituted by lower-aikoxy, tetrazolyl-lower-alkyl, trifluoromethylsulphonylamino-lower-alkyl or hydrogen. Other preferred groups of compounds of formula I are those in which R2 represents cyciohexyl or benzoyloxycyclohexyl; those in which R2 represents naphthyl, tetrahydronaphthyl or acenaphthyl; those in which R2 represents pyridyl or oxopyridyl or pyridyl or oxopyridyl substituted by 3H-2-thioxo-benzthiazolyl, lower-alkoxyphenyl-lower-alkoxy-lower-aikoxy, phenyl-lower-alkoxy-lower-alkoxy, phenyl-lower-alkyl, phenoxy-lower-alkyl or phenyl-lower-alkoxy-lower-alkyl; those in which R2 represents pyrimidinyl or pyrimidinyl substituted by benzodioxanyl-lower-alkoxy, biphenylyloxy, cyclohexyl-lower-alkoxy, cyclohexyloxy-lower-alkoxy, halophenyl-lower-alkoxy, halophenyl-oxadiazolyl-lower-alkoxy, indanyl-lower-alkoxy, naphthyl-lower-alkoxy, N-lower-alkyl-phenyl-lower-alkoxy-lower-alkylamino, lower-alkythio, lower-alkoxy, lower-alkoxyphenyl-lower-alkoxy-lower-alkoxy, lower-alkoxyphenyl-lower-alkylamino, lower-alkyl-pyridyl-lower-alkoxy, phenyl-lower-alkoxy-lower-alkoxy, phenyl-lower-alkoxy-lower-alkylthio, phenyl-lower-alkoxy-lower-alkylamino, phenyl-lower-alkenoxy, phenoxy-phenyl-lower-alkoxy, phenoxy-phenoxy, phenyl-lower-alkynyloxy, phenyl-lower-alkoxy-lower-alkoxy, phenylthio-lower-alkoxy, phenyl-oxazolyl-lower-alkoxy, phenyl-lower-alkynyloxy, phenyl-lower-alkenyloxy, phenyl-lower-alkylamino or phenyl-pyridyl-lower-alkylamino; and finally those in which R2 represents halobenzoyloxy-lower-alkyl-triazolyl, phenyl-lower-alkoxy-lower-alkyl-triazolyl or phenyl-lower-alkoxy-lower-alkoxy-lower-alkyl-triazolyl. Especially preferred are the following compounds: 4-[2-[7-[(3R,4R)-4-[4-(3-benzyioxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]-naphthalen-2-yloxy]-ethyl]-morpholine (R)-3-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]-naphthalen-2-yloxy]-propane-1,2-diol (S)-3-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]-naphthalen-2-yloxy]-propane-1,2-diol (R)-3-[2-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]-naphthalen-2-yloxy]-ethoxy]-propane- 1,2-diol (S)-3-[2-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]- piperidin-3-yloxymethyl]-naphthalen-2-yloxy]-ethoxy]-propane- 1,2-diol 1-[2-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin- 3-yloxymethyl]-naphthalen-2-yloxy]-ethyl]-4-methyI-piperazine 1-[(3R,4S-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yl]- 2-naphthalen-2-yl-ethanone (3R,4S,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-(l,4- dimethoxy-naphthalen-2-ylmethoxy)-piperidin-5-ol 3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-[7-[(R)-2,3- dihydroxy-propoxymethyl]-naphthalen-2-ylmethoxy]-piperidine (3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-[7-[(S)-2,3- dihydroxy-propoxymethyl]-naphthalen-2-ylmethoxy]-piperidine (3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-[6-[(R)-2,3- dihydroxy-propoxymethyl3-naphthalen-2-ylmethoxy]-piperidine (3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-[6-[(S)-2,3- dihydroxy-propoxymethyl]-naphthalen-2-ylmethoxy]-piperidine 4-[(3R,4S,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3- (naphthalen-2-ylmethoxy)-piperidin-5-yloxy]-butan-1-ol 3-[(3R,4S,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3- (naphthalen-2-ylmethoxy)-piperidin-5-yloxy3-propan-1-ol 1-{2-[(3R,4R,5S)-4-[4-(3-ben2yloxy-propoxy)-phenyl]-3- (naphthalen-2-ylmethoxy)-piperidin-5-yloxy]-ethyl}-4-methyl- piperazine (3R,4R,5R)-4-[2-[4-[4(3-benzyloxy-propoxy)-phenyl]-5- (naphthalen-2-ylmethoxy)-piperidin-3-ylmethoxy]-ethyl}- morpholine (3R,4S,5S)-4-[4-(3-benzyIoxy-propoxy)-phenyl]-3-(4-methoxy- benzyloxy)-piperidin-5-ol (3R,4s,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3,5-bis-(4- methoxy-benzyloxy)-piperidine (3S,4R,5R)-4-[2-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5- (naphthalen-2-ylmethoxy)-piperidin-3-ylmethoxy]-ethyl]- morpholine (3S,4R,5R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-methoxy- methyl-5-(naphthalen-2-ylmethoxy)-piperidine (3S,4R,5R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen- 2-ylmethoxy)-piperidin-3-ylmethyl [3-(4-methy!-piperazin-1 - yl)-propyl3-carbamate (3S,4R,5R)-4-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5- (naphthalen-2-ylmethoxy)-piperidin-3-ylmethylsulphanyl]- pyridine 2-(4-cyclohexyl-butoxy)-5-[(3R,4R)-3-( 1,4-dimethoxy- naphthalen-2-ylmethoxy)-piperidin-4-yl]-pyrimidine (3'R,4'R)-6-(3-cyclohexyl-propoxy)-3'-(1,4-dimethoxy- naphthalen-2-ylmethoxy)-r,2',3',4',5',6'-hexahydro- [3,4']bipyridine (3S,4R,5R)-[4-[4-(3-benzyloxy-propoxy)-phenyI3-5-(naphthalen- 2-ylmethoxy)-piperidin-3-yl]-methanol (3S,4R,5R)-N-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5- (naphthalen-2-ylmethoxy)-piperidin-3-ylmethyl]-N,N',N'- trimethyl-ethane-1,2-diamine (3S,4R,5R)-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen- 2-ylmethoxy)-piperidin-3-ylmethyl]-diethyl-amine 1-[(3R,4S,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(2- morpholin-4-yl-ethoxymethyl)-piperidin-3-yl]-2-naphthalen-2- y(-ethanone (3R,4R)-3-(1,4-dimethoxy-naphtha)en-2-ylmethoxy)-4-[4-[3-(2- methoxy-phenoxy)-propoxy]-phenyl]-piperidine (3R,4s,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3,5-bis-(3,4,5- trimethoxy-benzyloxy)-piperidine (3R,4R,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl3-3-(naphthaien- 2-ylmethoxy)-5-[1,2,4]triazol-l -yimethyl-piperidine (3R,4R)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]-phenyl]-3- (quinolin-7-ylmethoxy)-piperidine 2-(7-{(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyi]-piperidin-3-yloxymethyl}-naphthalen-2-ylmethoxy)-ethanol 7-{(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl3-piperidin-3-yloxymethyl}-naphthalen-2-ylmethyl)-dimethyl-amine (3R,4R)-3-(4-benzyloxy-naphthaIen-2-ylmethoxy)-4-(4-fluoro- phenyl)-piperidine (3'R,4'R)-3'-(1,4-dimethoxy-naphthaien-2-ylmethoxy)-6-[3-(2- methoxybenzyloxy)-propoxy]-1',2',3',4',5',6'-mexahydro- [3,4']bipyridine (3R,4R)-3-(1,4-dimethoxy-naphthalen-2-ylmethoxy)-4-[4-[3-(2- metlhoxy-benzyloxy)-propoxy]-plnenyl]-piperidine (3S,4R,5R)-1-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5- (naphthalen-2-ylmethoxy)-piperidin-3-ylmetlnyl3-imidazolidin-2- one (3R,4R)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy3-plienyl]-3-(2- 0X0-1,2-dilnydro-quinolin-7-yimethoxy)-piperidine, (3R,4R)-3-(isoquinolin-7-ylmethoxy)-4-[4-[3-(2-methoxy- benzyloxy)-propoxy]-phenyl]-piperidine, (3R,4R)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]-phenyl]-3- (1,2,3,4-tetrahydro-quinolin-7-ylmethoxy)-piperidine, l-[2-[7-[(3R,4R)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]- piperidin-3-yloxymethyl]-naphthalin-2-yloxy]-ethyl]-4-methyl- piperazine, l-[2-[7-[(3R,4S,5S)-5-hydroxy-4-[4-[-3-(2-methoxy-benzyloxy)- propoxy]-piperidin-3-yloxymetliyl]-naphtlnalin-2-yloxy]-etliyl]-4- methyl-piperazine, (3R,4S,5S)-3-(l,4-dimethoxy-naphtlialin-2-ylmethoxy)-4-[4-[3- (2-methoxy-benzyloxy)-propoxy]-phenyl]-piperidin-5-ol, (3R,4R,5S)-3-(1,4-dimethoxy-naphthalin-2-ylmethoxy)-4-{4-[3- (2-metlioxy-benzyloxy)-propoxy]-plienyl}-5-(1H-tetrazol-5- ylmethyl)-piperidine and (3'RS,4'RS)-3'-(1,4-dimethoxy-naphthalen-2-ylmetinoxy)-4-[3-(2-metlioxy-benzyloxy)-propoxy]-1',2',3',4',5',6'-hexalnydro-[1,4']bipyridin-2-one. The term "pharmaceutically usable salts" embraces salts with inorganic or organic acid such as hydrochloric acid, hydrobromic acid, nitric acid, sulphuric acid, phosphoric acid, citric acid, formic acid, maleic acid, acetic acid, succinic acid, tartaric acid, methanesulphonic acid, p-toluenesulphonic acid and the like. The compounds of formula I can be manufactured in accordance with the invention by cleaving off the protecting group(s) from a compound of formula II •■ ••111 in which P1 represents a protecting group and the remaining symbols have the significance given in claim 1 and hydroxy groups which may be contained in R1, R2 and R4 are present in protected form, if desired, functionally modifying reactive groups in the thus-obtained compound of formula I and/or converting the compound of formula I into a pharmaceutically usable salt, with the manufacture of 4-(4-fluorophenyl)-3-(3,4-methylenedioxy-benzyloxy)piperidine and its hydrochloride being excluded. The cleavage of a protecting group P1 and hydroxy protecting groups which may be present can be carried out in a manner known per se. Examples of protecting groups P1 are usual amino protecting groups such as tert-butoxycarbonyl, benzyloxy-carbonyl, vinyloxycarbonyl, alkylsilylalkyloxycarbonyl such as 2-(trimethylsilyl)ethoxycarbonyl, and trichloroethoxycarbonyl. Examples of hydroxy protecting groups are ether protecting groups such as tetrahydropyranyl, allyl, 2-(trimethylsilyl)ethoxy-methyl, trityl, tert-butyldimethylsilyl or ester protecting groups such as acetyl. The cleavage of these protecting groups is effected by acidic or basic hydrolysis, by hydrogenolysis, by reductive methods or by means of Lewis acids. A solution of a mineral acid such as hydrochloric acid, hydrobromic acid, sulphuric acid, phosphoric acid and the like in an inert solvent or solvent mixture is advantageously used for the acidic hydrolysis. Suitable solvents are alcohols such as methanol or ethanol, ethers such as tetrahydrofuran or dioxan, chlorinated hydrocarbons such as methylene chloride, and the like. Alkali metal hydroxides and alkali metal carbonates such as potassium hydroxide or sodium hydroxide or potassium carbonate or sodium carbonate, organic amines such as piperidine, and the like can be used for the basic hydrolysis. Inert organic solvents as referred to above for the acidic hydrolysis can be used as solubilizers. The reaction temperature for the acidic and basic hydrolysis can be varied in a range from 0 °C to the reflux temperature, with the reaction preferably being carried out at between about 0°C and room temperature. The tert-butoxycarbonyl group is conveniently cleaved off with hydrochloric acid, hydrogen chloride, trifluoro-acetic acid or formic acid in the presence or absence of an inert solvent. Furthermore, the tert-butoxycarbonyl group can be cleaved off by means of anhydrous zinc bromide in the presence of an inert solvent, preferably methylene chloride. The cleavage of the trichloroethoxycarbonyl group can be advantageously effected reductively with zinc in glacial acetic acid. The reaction temperature can lie in a range of 0°C to 40°C , with the reaction preferably being carried out at room temperature. The cleavage of the 2-(trimethylsilyl)ethoxycarbonyl group can be effected by means of fluoride ions in the presence of an inert solvent such as acetonitrile, dimethyl sulphoxide, dimethylformamide or tetrahydrofuran, preferably by means of tetrabutylammonium fluoride in tetrahydrofuran, at temperatures from about 0°C to about room temperature. The compounds of formula II are novel and are also an object of the invention. Their preparation is described in more detail hereinafter in Schemes 1-15 and in the Examples. In accordance with Scheme 1 compounds of general formula 3. can be obtained by reacting compounds of general formula 1 in a manner known per se with metal-organic derivatives, preferably lithium or magnesium derivatives, prepared from compounds of general formula 2. wherein Ra represents hydrogen or a substituent which is inert under the reaction conditions or in which reactive groups are present in protected form. Preferably, compounds 2. in which Ra represents halogen, lower-alkoxy or benzyloxy are used and these substituents are utilized for the synthesis of another desired substituent at an appropriate later stage of the reaction sequence. The reaction with such a metal-organic compound 2. is effected according to methods known per se, for example in a solvent which is inert under the reaction conditions, such as an ether, at a temperature between about -78°C and 75°C . The compounds of general formula 6 can be obtained therefrom in the presence of an acid or another water-cleaving reagent, optionally in the presence of a base, in an organic solvent. As acids there come into consideration e.g. hydrochloric acid, trifluoroacetic acid or p-toluenesulphonic acid, and as the water-cleaving reagent there can be used e.g. phosphorus oxytrichloride in pyridine. The reaction temperature lies between 0-120°C ; as solvents there can be used e.g. toluene, dimethylformamide or alcohols. Compounds of general formula 6 can also be obtained directly starting from a compound of general formula 4 in which Tf is an activating group such as trifluoromethylsulphonyl (triflate) by reaction with a metal-organic compound, especially a tin derivative of general formula 5 in which R is lower-alkyl, e.g. butyl, or a corresponding arylboric acid derivative using a suitable catalyst such as e.g. tetrakis-triphenylphosphine-palladium in an inert solvent such as dioxan, dimethoxyethane or dimethylformamide at temperatures between room temperature and 1 50°C Compounds of general formula Z can be obtained from compounds of general formula 6 by hydroboration and subsequent basic oxidative working-up. The hydroboration can be effected according to methods known per se, for example in a solvent which is inert under the reaction conditions, such as an ether, e.g. 1,2-dimethoxyethane, at a temperature between about 0°C and 70°C , and with a diborane-containing or diborane-liberating reagent such as e.g. borane in tetrahydrofuran or a mixture of sodium borohydride and boron trifluoride etherate. The carbo-boranes which are formed as intermediates can be converted into the secondary alcohols of general formula 1_ by reaction with bases, e.g. potassium hydroxide, and an oxidizing agent, e.g. hydrogen peroxide, at a temperature between about room temperature and 120°C . Compounds of general formula 8. in which Ra is halogen, cyano, trifluoromethyl, lower-alkyl, lower-alkoxy-lower-alkyl, lower-alkoxy or lower-alkylenedioxy can be obtained from 1_ by alkylation with a compound which yields the group R1. The alkylation of the secondary alcohol is effected according to methods known per se, for example in a solvent which is inert under the reaction conditions, such as an ether, e.g. tetrahydro¬furan or 1,2-dimethoxyethane, or dimethylformamide, with the aid of an alcoholate-forming base, e.g. sodium hydride, at a temperature between about 0°C and 40°C and using a halide, preferably chloride or bromide, or a suiphonic acid ester, e.g. a mesylate or tosylate, as the compound which yields R1i. Compounds of formula Z in which Ra is lower-alkoxy can be converted into compounds of general formula 9£ by an alkyl-aryl ether cleavage. The ether cleavage is effected according to methods known per se by, preferably starting from compounds in which Ra has the meaning methoxy, reacting the alkyl-aryl ether with mineral acids such as hydrobromic acid or hydroiodic acid or preferably with Lewis acids such as boron trichloride or boron tribromide in a solvent which is inert under the reaction conditions, such as e.g. a halogenated hydrocarbon, at a temperature between about -10°C and room temperature. Compounds of general formula 9 can be used as starting materials for the preparation of compounds of general formula 10 in which Rb is a group -Tl-L1-T2-L3-TS-L4-T4-U, T"! is oxygen, (m), (o) or (p) and the remaining symbols L2,3,4, T2.3,4 and U can have the meanings referred to earlier. The linkage of the group -L2-T2-L3-T3-L4-T4-U can be effected selectively by reaction with a derivative of the group to be introduced which carries a suitable leaving group, although the desired group can also be built up stepwise. The selective linkage with the phenolic alcohol is effected according to alkylation or acylation methods which are known per se in the presence of a base such as potassium carbonate. Chlorides, bromides, iodides, tosylates or mesylates come into consideration as alkylating agents. The reaction is effected in a solvent which is inert under the reaction conditions, such as e.g. an ether such as tetrahydrofuran or an aromatic hydrocarbon such as e.g. toluene, pyridine, acetone or methyl ethyl ketone, at a temperature between about 0°C and 100°C . Suitable acylating agents are activated derivatives such as optionally activated esters, acid halides, acid anhydrides or mixed acid anhydrides. The reaction is effected in a solvent which is inert under the reaction conditions, such as e.g. an ether such as tetrahydrofuran, an aromatic hydrocarbon such as e.g. toluene, a chlorinated hydrocarbon such as methylene chloride or chloroform, and the like at a temperature between about 0°C and 50°C . Reactive groups such as keto or hydroxy groups contained in addition to the leaving group in the group to be introduced are preferably present in a form which is protected in a suitable manner, e.g. in the form of acetals, esters, carbamates, silyl derivatives and the like. After cleavage of these protecting groups a stepwise synthesis of the group -T'-L2-T2-L3-T3-L4-T4-U can be continued. The thus-obtained compounds containing a hydroxy group in the piperidine ring can be alkylated as described above for the conversion of Z into 8. Compounds of formulae 12-1 6 can be prepared in accordance with Scheme 2 starting from compounds of general formula 11 in which Rc is chlorine, bromine, iodine as well as hydroxy in the form of an activated derivative such as e.g. the triflate and R15 is hydrogen or a group which is inert under the reaction conditions by carrying out palladium-catalyzed couplings in a manner known per se with carbon monoxide, cyanides, amines or compounds of the general formulae H2C=CH-R19 or HC=C-R19 wherein R19 is -COOR16, -CN or -OR20. As palladium catalysts there can be used complexes, prepared in situ, of e.g. PdCl2(CH3CN)2 or Pd(0Ac)2 with 1,1'-bis(diphenyl-phosphino)ferrocene, 1,3-bis(diphenylphosphino)propane or tri(o-tolyl)phosphine. The group -HC=CH-RT9 or -C=C-R19 in the thus-obtained compounds can be derivatized for a further stepwise synthesis of a substituent L1-T1-L2-T2-L3-T3-L4-T4-U. A C=C triple bond can be converted into a double bond and the latter can be converted into a single bond. A cyano group can be converted into an amide, an aldehyde, an acid, an ester or an amine. Compounds of formula 13. with R17,18 = benzyl can be debenzylated and the thus-formed sec. or prim, amino group can also be utilized for a further derivatization. All of these transformations or derivatizations, which are presented in a non-limiting manner in Schemes 3-9, can be undertaken according to methods known per se. Compounds of general formulae 17-22 can be obtained in accordance with Scheme 3 from compounds of general formula 12, obtained by reaction of compounds of general formula 11 with carbon monoxide by means of palladium catalysis. Compounds of general formulae 24-29 can be obtained in accordance with Scheme 4 from compounds of general formula 23., obtained by reaction of compounds of general formula 11. with acrylic acid esters by means of palladium catalysis. Compounds of general formulae 31-34 can be obtained in accordance with Scheme 5 from compounds of general formula 30, obtained by reaction of compounds of general formula 11 with acrylonitrile by means of palladium catalysis. Compounds of general formulae 36-40 can be obtained in accordance with Scheme 6 from compounds of general formula 35., obtained by reaction of compounds of general formula 11 with vinyl ethers by means of palladium catalysis. The piperidones of general formula 41 can be used as starting materials for the synthesis of the piperidine derivatives I analogously as described for the piperidone 1. They can be obtained analogously to the process of A.H. Beckett et al described in the Journal of Medicinal and Pharmaceutical Chemistry Vol 1(1), 37-58 (1959). The piperidones of general formula 41 can be obtained by intramolecular ring-closure of a propionic acid derivative of general formula 42., in which R4 is as defined earlier or represents a substituent, which is inert under the reaction conditions or wherein reactive groups are present in an appropriately protected form. Preferably, R4 is choosen in a manner to make it possible to optionally construe another desired substituent at an appropriate later stage of the reaction sequence, p1 has the meaning of methyl or benzyl. The ring closure is carried out in the presence of a base such as e.g. sodium alcoholate, sodium hydride or sodium dispersion in xylene. The subsequent decarbalkoxylation of a thus-obtained compound of general formula 43 or 44 by means of hydrochloric acid leads to compounds of general formula 41. Derivatives of general formula 43. in which R4 signifies allyl or benzyl can also be prepared in a direct manner by C-alkyl-ation of the sodium salt of a compound of general formula 45. by means of allyldimethylanilinium bromide or benzyldimethyl-anilinium bromide analogously to the process described by A.H.Beckett et al. (see above). Derivatives of general formula 41 in which R4 signifies hydroxymethyl which is suitably protected at the hydroxy function can also be obtained from the compound of general formula 45. by reduction to the diol analogously to the process described by E.Jaeger und J.H.Biel in J.Org.Chem. 30(3), 740-744 (1965), introduction of a suitable protecting group for the primary alcohol, e.g. trityl, and oxidation of the secondary alcohol obtained. Furthermore, derivatives of general formula 46. can be prepared by hydroxymethylating compounds of general formula 6 analogously to the process of K. Willcocks et al. described in the Journal of Labelled Compounds and Radiopharmaceuticals Vol. XXXIII, No.8, 783-794 (1993). Compounds of general formula II in which R3 has the meaning hydrogen and W has the meaning oxygen or sulphur can be obtained starting from compounds of general formula 47 by epoxidation. Compounds of general formula 47 can be prepared according to the process described by M.Ferles and M.Jankovsky in Coll.Czechoslov.Chem.Commun. Vol, 35, 2802-2809 (1970). The epoxides can then be opened by reaction with suitable thio-phenolates and phenolates as described by R. Paioni in German Offenlegungsschrift 2738477. The further synthesis to compounds of formula II can be effected as described previously. Scheme 7 In accordance with Scheme 7 compounds of general formula 51 can be obtained from compounds of general formula 46 by firstly reducing the double bond using complex hydrides such as lithium aluminium hydride as described by J.M. Lundbeck et al. in European Patent Application E.P. 0 374 674 or sodium dihydrido-bis-(2-methoxyethoxy)aluminate in a solvent which is inert under the reaction conditions, such as tetrahydrofuran, dioxan or toluene, at temperatures between room temperature and 11 0°C or hydrogenating the double bond with hydrogen using a catalyst, with compounds of general formula 48. being obtained. Compounds of general formula 48. can be converted into the corresponding aldehydes of general formula 49. by a usual oxidation process, e.g. using oxalyl chloride and dimethyl sulphoxide as described by A.J. Mancuso and D. Swern in Synthesis 1981, 165. The condensation of aldehydes of general formula 49. with Grignard or lithium compounds in a solvent which is inert under the reaction conditions, such as ether, tetrahydrofuran or dioxan, at temperatures between -80°C and room temperature leads to compounds of general formula 5.0 which can be converted according to known processes into the corresponding ester or ether compounds of general formula 51. Scheme 8 In accordance with Scheme 8 compounds of general formula ^ are obtained by brominating compounds of general formula 1 in a solvent which is inert under the reaction conditions, such as chloroform or methylene chloride, and using a buffer salt such as disodium hydrogen phosphate at temperatures between 0°C and 50°C to firstly form compounds of general formula 52., reaction of which with an alkali metal salt of a thiol in a solvent such as acetone, acetonitrile or dimethylformamide at temperatures between room temperature and 100°C gives compounds of general formula .53.. Condensation of these with Grignard or lithium compounds in inert solvents such as ether, tetrahydrofuran or dioxan at temperatures between -80°C and room temperature then yields compounds of general formula 54. Scheme 9 In accordance with Scheme 9 compounds of general formula 56 can be obtained by dihydroxylating compounds of general formula 6 to compounds of general formula 55. Alkylation of these yields, according to previously described processes, compounds of general formula .56. The dihydroxylation can be effected according to processes known per se, for example in a solvent which is inert under the reaction conditions, such as acetone or tert-butanol, at a temperature between 0°C and 50°C, preferably at room temperature, with a hydroxylating reagent such as e.g. a mixture of osmium tetroxide and hydrogen peroxide. The compounds prepared in Schemes 2-9 can, moreover, be used as described above as starting materials for a further synthesis of a substituent -Ll -Tl -L2-T2-L3-T3-L4-T4-U optionally present in R2, Furthermore, compounds of general formula II in which an ethylene bridge Q is present can be prepared in accordance with the processes described in Schemes 1-9 as well as the processes described hereinbefore and in more detail in the Examples. The tropinones of general formula 57 usable as starting materials can be prepared, inter alia, according to the processes described by M.Lounasmaa and CJ.Johansson in Tetrahedron Letters, No.29, 2509 (1974) or O.Kovacs et al. in Helv.Chim.Acta Vol. XXXVII, 802 (1954). Derivatives of general formfula 57 can be obtained from the compound of general formula 58 according to the process described by O.Kovacs et al. in Helv.Chim.Acta Vol. XXXVII, 802 (1954) by reduction to the diol, introduction of a suitable protecting group for the primary alcohol, e.g. trityl, and oxidation of the secondary alcohol obtained. Herein, R4 is as defined earlier or is a substituent which is inert under the raction conditions or wherein any reactive groups are present in protected form and are preferably choosen in a manner to make the construction of another desired substituent at an appropriate, later stage of the raction sequence possible. Furthermore, derivatives of general formula 59 in which R4 signifies hydroxymethyl can be prepared by hydroxymethylating compounds of general formula 60 analogously to the process of K.Willcocks et al. described in Journal of Labelled Compounds and Radiopharmaceuticals Vol. XXXIII, No.8, 783-794 (1993). Furthermore, there exists the possibility of preparing derivatives of general formula 57 starting from correspondingly substituted acetonedicarboxylic acid derivatives by a reaction with succindialdehyde and an amine analogously to procedures known in the literature, with the corresponding tropinone derivative being synthesized. The substituted acetone¬dicarboxylic acid derivatives used as starting materials can be prepared according to the procedures described by l.lto and S.I.Nagai in Chem.Pharm.Bull. 22(9) 2131 (1974) or T.Arslan and S.A.Benner in J.Org.Chem. 58, 2260 (1993). One possible synthetic route to 4-aryl-piperidines which are substituted in each of positions 3 and 5 with 0 or N atoms is shown in Scheme 10. Oxirane compounds of general formula LXI can be formed from olefins 6, for example, via a bromohydrin which is formed as an intermediate and which can be obtained by the addition of bromine in aqueous dioxan. Subsequently, the bromohydrin can be ring-closed to the epoxide 61 by the addition of aqueous sodium hydroxide solution. Treatment of such an oxirane with methyllithlum, butyllithium or a lithium amide in aprotic solvents such as ether or tetrahydrofuran at temperatures between -80°C and +6O°C leads to allyl alcohols 62. which, with a free OH or after the introduction of an ether function R20, can be further processed. Hydroboration of these allyl alcohol derivatives 62., as described earlier for the preparation of compounds of general formula Z, yields the free or monofunction-alized dihydroxy derivatives 63.. For the structural variation of the group R20 (R4azi. or H), -ZR1 and Ra, depending on the target molecule being prepared, groups R20 and -ZRi can be introduced in a different sequence and group Ra can be modified to Rb, a group of the general formula -T1-L2-T2-L3-T3-L4-T4-U. It can be advisable to provide one of the two OH functions intermediately with a protecting group and to cleave this off at a later stage of the synthesis or to choose the groups -ZR1 and R20 such that, if desired, it is possible to synthesize another desired substituent at a suitable later stage of the reaction sequence. Starting from monoether-protected derivatives 65 the free OH function can, for example, be stereochemically inverted by reaction with formic acid, triphenylphosphine and an azodicarboxylic acid ester in an inert solvent such as tetrahydrofuran according to Mitsunobu [Synthesis 1981, 1], with compounds of general formula M being obtained. The use of diphenylphosphoryl azide in place of formic acid under similar conditions provides a possibility of introducing, starting from compounds 66 by a renewed inversion at the same centre, an azido function which can be converted into a primary amino function, for example, by reduction with triphenylphosphine/water in tetrahydrofuran at temperatures between room temperature and 80°C [Synth. Commun. 17, 377 (1987)]. There are thus obtained compounds of general formula 67. which can be subsequently alkylated or acylated. In accordance with Scheme 11 cinnamic acid derivatives ^, which are known from the literature, can be converted with malonic acid monoester monoamides 63. in protic solvents such as ethanol or methanol or aprotic solvents such as N,N-dimethyl-formamide, dimethyl sulphoxide, tetrahydrofuran or acetonitrile using bases such as, for example, potassium tert-butylate or sodium hydride at temperatures between room temperature and 130°C into cyclic imides 70. Reduction of these imides 70 with hydride reducing reagents such as lithium aluminium hydride, diisobutyl aluminium hydride or sodium dihydrido-bis-(2-methoxyethoxy)aluminate in aprotic solvents such as ethers, tetrahydrofuran or dioxan at temperatures between room temperature and 120°C yields the piperidine mono- and dimethanols Zl, which can be provided at the piperidine nitrogen with a suitable protecting groups. Mono- and dihydroxy compounds of general formula 71 can now be selectively functionalized stepwise in an analogous manner to that described earlier for mono- and dihydroxy compounds Z, 10., 62., 6.2., 64 or by conversion into the corresponding bromo, chloro or iodo compounds or aryl- or alkylsulphonic acid esters and subsequent nucleophilic substitution with alcoholates, phenolates or thiophenolates according to conventional methods. Thereby, ZRl, Z1R4a can represent substituents as defined earlier in general formula I or suitable precursors, which are inert under the reaction conditions or in which reactive groups are present in appropriately protected form, preferably chosen such that, if desired, it is possible to synthesize another desired substituent at a suitable later stage of the reaction sequence. Ra and Rb correspond to the definitions set forth above. Alternatively, monohydroxy compounds Zl, dihydroxy compounds Zl or derivatives 73. of the dihydroxy compounds Zi, the hydroxy function of which has been structurally modified, can be converted into the aldehydes Zd by oxidation, for example according to Swern (dimethyl sulphoxide, oxalyl choride) [J. Org. Chem. 43, 2480 (1978)]. Addition of a Grignard compound or lithium compound according to known methodology in an inert solvent such as tetrahydrofuran or 1,2-dimethoxyethane at temperatures between -78°C and room temperature then yields the alcohols 76. (R9 = H), which can be optionally alkylated, acylated or again oxidized, for example according to Swern, and thus give derivatives 76. (R9 other than H) or, respectively ketones ZZ- Compounds of general formula 73. and 80 can be obtained starting from dihydroxy compounds 71 by simultaneous conversion of both hydroxy functions analogously to that described above via dialdehydes 715.. The transformation of aldehydes 74, 75. into ketones ZZ, 80. can also be effected via an oxidation to the acids [for example with sodium chlorite, amidosulphonic acid and isopropenyl acetate in a solvent such as acetone/water at 0°C to room temperature according to J. Am, Chem Soc. 110, 2242 (1988)], subsequent amide coupling to N-methyl-N-methoxy amides with N,0-dimethylhydroxylamine according to known methods as well as reaction thereof with organolithium or organomagnesium compounds in an inert solvent such as tetrahydrofuran or 1,2-dimethoxyethane at temperatures between -78°C and room temperature as described, for example, in [Synthesis 1986, 944]. Ketones ZZ can be converted into oximes ZE in which R10 can have the significance defined in general formula I by reaction with optionally substituted hydroxylamine derivatives in a solvent such as pyridine in the presence of catalytic or stoichiometric amounts of a strong acid at temperatures between room temperature and 120°C . Compounds of general formulae 88. and 90, which contain heterocyclic substituents in the 4-position of the piperidine ring, can be synthesized stepwise in accordance with Scheme 12, e.g. as described hereinafter. 4-Heteroaryl-1,2,3,6-tetrahydro-pyridine derivatives M can be obtained, for example, from 1,2,3,6-tetrahydro-pyridine derivatives 81 activated in the form of an enol triflate by condensation with suitable functionalized heteroaromatic compounds activated, for example, in the form of tin compounds. Coupling reactions of this type are preferably carried out in an inert solvent such as 1,2-dimethoxyethane, tetrahydrofuran or N,N-dimethylformamide using a catalyst such as tetrakis-(triphenylphosphine)-palladium at temperatures up to 130°C . In place of tin compounds there can also be used analogous boric acid derivatives 82. under comparable reaction conditions or a vinyl-tin compound 81. which is analogous to the enol triflate 8J_ can be reacted with heterocyclic halo compounds or triflates 82. likewise under comparable conditions; in both cases the reactions lead to the same products. 4-Heteroaryl-l ,2,3,6-tetrahydro-pyridine derivatives 86. can, however, also be obtained from pyridyl-heteroaryl-biaryl derivatives such as 84: according to known methods: N-methylation, partial hydrogenation of the methylated pyridine ring with a suitable hydride reagent such as sodium borohydride and subsequent conversion of the N-methyl function into a suitable protecting group by demethylating carbamoylation [as described, for example, in J. Org. Chem. 49, 2081 (1984)]. Compounds of general formulae 87 and 89 can be obtained by hydroboration and subsequent basic oxidative working-up of compounds of general formulae 83. and 86- The hydroboration can be effected according to methods known per se, for example in a solvent which is inert under the reaction conditions, such as an ether, e.g. 1,2-dimethoxyethane, at a temperature between about 0°C and 70°C , and with a reagent which contains or liberates diborane, such as e.g. borane in tetrahydrofuran, borane-dimethyl sulphide or a mixture of sodium borohydride and boron trifluoride etherate. The carboboranes which are formed as intermediates can be converted into the secondary alcohols of general formula 87 and 89. by reaction with bases, e.g. potassium hydroxide, and an oxidizing agent, e.g. hydrogen peroxide, sodium perborate or sodium percarbonate, with a combination of base and oxidizing agent or with trimethylamine N-oxide without the addition of base at a temperature between about room temperature and 120°C . Compounds of general formulae 88. and 9.0 in which -ZRi represents a substituent containing an aryl or heteroaryl function can be obtained from compounds of general formulae 8Z and 89. by alkylation with a compound which yields the group -ZRi, Alkylation of the secondary alcohol is effected according to methods known per se, for example in a solvent which is inert under the reaction conditions, such as an ether, e.g. tetrahydro-furan or 1,2-dimethoxyethane, or dimethylformamide, with the aid of an alcoholate-forming base, e.g. sodium hydride, at a temperature between about 0°C and 400°C and using a halide, preferably a chloride or bromide, or a sulphonic acid ester, e.g. a mesylate or tosylate, as the compound which yields -ZRl. The group Ra can be structurally modified prior to or after the alkylation described above. Modification reactions of group Ra to Rb, a group of the general formula -TT-L2-T2-L3-T3-L4-T4-U, include usual transformation reactions such as removal and re-introduction of a functional group, alkylation and acylation of alcohol and amine functions, oxidations of sulphides to sulphoxides and sulphones as well as other transformation reactions which are well d0°C umented in the literature. Examples of specific structural transformations of group Ra to group RP are compiled in Scheme 13: 2-Methylsulphonyl pyridine and pyrimidine derivatives 91, which are already appropriately substituted in the 3-position of the piperidine, can be converted into the correspondingly substituted heteroaryl compounds with aicoholates, thiolates and amines in tetrahydrofuran, 1,2-dimethoxyethane, dimethyl-formamide or dimethyl sulphoxide at temperatures between room temperature and about 150°C . Phenolic pyridine or pyrazine derivatives 92., which have a OH or OZRl function in the 3-position of the piperidine, can be alkylated at the phenolic 0 function using a base and an alkylating agent according to known methods, in which case varying amounts of N-alkylation products can result. On the other hand, when the reaction is carried out with an alcohol in the presence of triphenylphosphine and an azodicarboxylic acid ester in a solvent such as tetrahydrofuran or 1,2-dimethoxyethane according to Mitsunobu [Synthesis 1981, 1], then O-alkylation products are formed almost exclusively. Accordingly, in the reaction products of general formulae 93-96 -OR22, -R6NR22 and -SR22 each represent a group -T 1-L2-T2-I_3-T3-L4-T4_U, in which T1 = oxygen, nitrgen or sulphur. Compounds of general formulae 104. 105 as wel as 108 to 110 can be obtained from oxirane compounds 98. in accordance with Scheme 14. Oxirane compounds 98 can be obtained by oxidation of the corresponding olefins by means of peracids such as peracetic acid or perbenzoic acid, preferably 3-chloro-perbenzoic acid. They can be converted into azido compounds 101 with azide anions in protic solvents such as ethanol or methanol or in aprotic solvents such as N,N-dimethylformamide, aceto-nitrile or dimethyl sulphoxide with or without the addition of Lewis acids such as lithium perchlorate or magnesium sulphate at temperatures between 50°C and 150°C, with varying amounts of epoxide-opened products having the azido function in the 3-position and the OH function in the 4-position of the piperidine ring being formed. The undesired isomeric compounds having the azido function in the 3-position of the piperidine ring can be separated, for example, by chromatography on silica gel. After the introduction of a suitable ether function in the 3-position the azido compounds can be converted by condensation with a suitable acetylene compound 103. such as, for example, propargyl alcohol in an apolar solvent such as toluene or xylene at temperatures between 60°C and 160°C , into the two isomeric N-triazolyl compounds of general formulae 104 and 105. Both give potent renin inhibitors after the introduction of a suitable side-chain on the substituents of the triazole ring using specific modification reactions of group Ra to Rb such as removal and re-introduction of a functional group, alkylation and acylation of alcohol and amine functions, oxidations of sulphides to sulphoxides and sulphones as well as other transformations which are well d°C umented in the literature and after cleavage of the protecting group on the nitrogen atom of the piperidine ring. Compounds of general formula 106 can be synthesized by the nudeophilic opening of oxiranes of general formula 98. with an anion obtained from the substituted pyridone. The nudeophilic opening can be effected according to methods known per se, for example in a solvent which is inert under the reaction conditions, such as e.g. aceto-nitrile, 1,2-dimethoxyethane or N,N-dimethylformamide, at a temperature between about room temperature and 120°C and using a catalyst, e.g. ammonium chloride or lithium perchlorate. with the isomeric epoxide-opened product which °C curs in varying amounts conveniently being separated by chromatography on silica gel. Compounds of general formula 109 can be obtained starting from compounds of general formula 98. by firstly performing a nucleophilic opening of the oxiranes by means of cyanide ions to give compounds of formula 99.. The nucleophilic opening can be effected according to methods known per se, for example in a solvent which is inert under the reaction conditions, such as e.g. acetonitrile, 1,2-dimethoxyethane or N,N-dimethyl-formamide, at a temperature between about room temperature and 120°C and using a catalyst, e.g. ammonium chloride, zinc trifluoroacetate or lithium tetrafluoroborate, especially lithium perchlorate, with the isomeric epoxide-opened product which °C curs in varying amounts conveniently being separated by chromatography on silica gel. Compounds of general formula 1 07 can be obtained from compounds of general formula 99 by the direct addition of ammonia or via the corresponding thioamides of general formula 100. The addition can be effected according to methods known per se, for example by reacting the nitrile under pressure with ammonia and ammonium chloride or by reacting sulphuretted hydrogen, preferably in the form of a hydrogen sulphide, with the nitrile to give the thioamide of general formula 100. This can be further converted, e.g. according to the pr°C edure described in Helv.Chim.Acta Vol. 69, 1224 (1986), by alkylation with methyl iodide or ethyl iodide into the correspond¬ing sulphonium derivative, ammonolysis of which, e.g. with ammonium chloride, leads to the amidine of general formula 107. Compounds of general formula 109 can be prepared by a ring-closure reaction of the amidine of general formula 1 07 with a corresponding malondialdehyde. The synthesis of the pyrimidine unit can be effected according to pr°C edures known per se, for example by reaction of the amidine with a diacetal or enamine of the 2-substituted malondialdehyde in a solvent which is inert under the reaction conditions, such as e.g. methanol, at a temperature between about room temperature and 120°C . Depending on the target molecule under preparation, starting from compounds 106 and 109 firstly -ZRi can be introduced and subsequently group Ra can be modified to Rb or a reversed synthetic route can be used. Scheme 15 Compounds of general formula 113 can be obtained from compounds of general formula 99. in accordance with Scheme 1 5 by firstly alkylating the secondary alcohol with a compound which yields the group Z-R1, whereby, if desired, the further synthesis of the desired substituents can be effected at a later stage of the reaction sequence. The alkylation of the secondary alcohol is effected according to procedures known per se, for example in a solvent which is inert under the reaction conditions, such as an ether, e.g. tetrahydrofuran or 1,2-dimethoxyethane, or dimethylformamide, with the aid of an alcoholate-forming base, e.g. sodium hydride, at a temperature between about 0°C and 40°C and using a halide, preferably a chloride or bromide, or a sulphonic acid ester, e.g. a mesylate or tosylate, as the compound which yields Z-R1. The reaction of compounds of general formula 111 with hydroxylamine in the presence of a base such as e.g. sodium methylate, conveniently at temperatures between 40°C and 100°C , gives amidoxines of general formula 11 2. Compounds of general formula 11 3 are obtained by reacting a reactive functional derivative of a carboxylic acid of general formula 11 8 with an amidoxime of formula 11 2. The reaction is conveniently effected by heating for several hours to about 70°C to 130°C in an inert solvent, e.g. in dimethylformamide. The non-cyclized conden¬sation product which is formed as an intermediate cyclizes spontaneously under the given reaction conditions. As reactive functional derivatives of carboxylic acids of general formula 1 1 8 there can be used the corresponding imidazolides, which can be prepared from the corresponding free carboxylic acids according to procedures known per se, e.g. by reaction with 1,1'-carbonyl-diimidazole in an inert organic solvent, e.g. in dimethyl¬formamide. Furthermore, as reactive functional derivatives of the carboxylic acids there can also be used carboxylic acid chlorides which can be prepared from the corresponding free carboxylic acids by means of thionyl chloride or oxalyl chloride. Compounds of general formula 116 can be obtained from compounds of general formula 114 firstly, as mentioned above, by alkylating compounds of general formula 11 5. These are then converted into reactive, functional derivatives of the carboxylic acid and reacted with hydrazides of general formula 11 9. The reaction is conveniently effected at room temperature to 50°C in an inert organic solvent, e.g. in dimethylformamide. The non-cyclized condensation product which thereby results can be isolated and then cyclized to compounds of general formula 11 6 by heating for several hours with polyphosphoric acid at about 100°C . Compounds of general formula 117 can be obtained from compounds of general formula 11 5 in accordance with Scheme 15 by reacting reactive, functional derivates of the carboxylic acids with amidoximes of general formula 1 20. The reaction is conveniently effected by heating for several hours to about 70°C to 130°C in an inert solvent, e.g. in dimethylformaide. The non-cyclized condensation product which is formed as an intermediate cyclises spontaneously under the given reaction conditions. The compounds of general formulae 114 and 11 8 - 120 belong to generally known classes of compound and will therefore be readily accessible to any person skilled in the art. Furthermore, compounds of general formula II in which R2 has the meaning of a 5-membered aromatic group can also be prepared very similarly to the synthesis route described in Scheme 12, in which the specifically functionalized 6-membered aromatic synthone 82. must be replaced by a corresponding 5-membered aromatic synthone. Piperidines of general formula I can also exist in optically pure form. Separation into antipodes can be effected according to methods known per se, either preferably at an early stage of the synthesis by salt formation with an optically active acid such as, for example, (+)- or (-)- mandelic acid and separation of the diastereomeric salts by fractional crystallization or preferably at a later stage by derivatization with a chiral auxilary substance such as, for example, (+)- or (-)- camphamoyi chloride and separation of the diastereomeric products by chromatography and/or crystallization and subsequent cleavage of the bond to the chiral auxilary substance. In order to determine the absolute configuration of the piperidine obtained, the pure diastereomeric salts and derivatives can be analyzed by conventional spectro- scopic methods, with X-ray spectroscopy on single crystals being an especially suitable method. The compounds of formula I and their pharmaceutically usable salts have an inhibitory activity on the natural enzyme renin. The latter passes from the kidneys into the blood and there brings about the cleavage of angiotensinogen with the formation of the decapeptide angiotensin I which is then cleaved in the lungs, the kidneys and other organs to the °C tapeptide angiotensin II. Angiotensin II increases blood pressure not only directly by arterial constriction, but also indirectly by the liberation of the sodium ion-retaining hormone aldosterone from the adrenal gland, with which is ass°C iated an increase in the extracellular fluid volume. This increase is attributed to the action of agiotensin II itself or to the hepapeptide angiotensin III which is formed therefrom as a cleavage product. Inhibitors of the enzymatic activity of renin bring about a decrease in the formation of angiotensin I and as a consequence of this the formation of a smaller amount of angiotensin II. The reduced concentration of this active peptide hormone is the direct reason for the blood pressure-lowering activity of renin inhibitors. The in-vivo potency of renin inhibitors can, as described by W.Fischli et al. in Hypertension, Vol. 18 (1), 22-31 (1991) or Hypertension Vol. 22 (1), 9-17 (1993) be demonstrated experimentally by means of the tests described hereinafter. The tests can be carried out in analogy to those described by D.T.Pals et al. in Hypertension Vol 8, 1105-1112 (1986) or J.Boger et al. in J.Med.Chem. 28, 1779-1790 (1985) or J.F.Dellaria et al. in J.Med.Chem. 30, 2137-2144 (1987) or T.Kokubu et al. in Bi°C hem.Biophys.Res.Commun. 118, 929-933 (1984). In vitro test with pure human renin The test is carried out in Eppendorf test tubes. The incubation mixture consists of (1) 100 ml of human renin in buffer A (0.1 M sodium phosphate solution, pH 7.4, containing 0.1% bovine serum albumin, 0.1% sodium azide and 1 mM ethylene- diaminetetraacetic acid), sufficient for a renin activity of 2-3 ng of angiotensin l/ml/hr.; (2) 145 ml of buffer A: (3) 30 ml of 10 mM human tetradecapeptide renin substrate (hTD) in 10 mM hydr°C hloric acid: (4) 15 mi of dimethyl sulphoxide with or without inhibitor and (5) 10 ml of a 0.03 molar solution of hydroxyquinoline sulphate in water. The samples are incubated for three hours at 37°C and, respectively, 4°C in triplicate. 2 x 100 ml samples per test tube are used in order to measure the production of angiotensin I via RIA (standard radioimmunoassay; clinical assay solid phase kit). Cross reactivities of the antibody used in the RIA are: angiotensin I 100%; angiotensin II 0.0013%; hTD (angiotensin l-Val-lle-His-Ser-OH) 0.09%. The production of angiotensin I is determined by the difference between the test at 37°C and that at 4°C . The following controls are carried out: (a) Incubation of hTD samples without renin and without inhibitor at 37°C and 4°C . The difference between these two values gives the base value of the angiotensin I production. (b) Incubation of hTD samples with renin, but without inhibitor at 37°C and 4°C. The difference between these values gives the maximum value of the angiotensin I production. In each sample the base value of the angiotensin I production is subtracted from the angiotensin I production which is determined. The difference between the maximum value and the base value gives the value of the maximum substrate hydrolysis (= 100%) by renin. The results are given as IC50 values which denote that concentration of the inhibitor at which the enzymatic activity is inhibited by 50%. The IC50 values are determined from a linear regression curve from a logit-log plot. The results obtained in this test are compiled In the following Table: Table Compound IC50 values in µMolA A 0.011 B 0.026 C 0.070 D 0.040 E 0.041 F 0.057 G 0.033 H 0.073 I 0.317 J 0.017 K 2.600 L 3.080 M 0.008 N 0.012 0 0.017 P 0.006 Q 0.005 R 0.003 S 0.002 T 0.005 U 0.024 V 0.002 W 0.002 X 0.003 Y 0.003 Z 0.001 A A 0.001 BB 0.003 CC 0.002 DD 0.001 EE 0.0004 FF 0.0006 GG 0.001 HH 0.006 I I 0.002 J J 0.002 KK 0.012 LL 0.001 MM 0.0005 NN 0.001 00 0.006 PP 0.002 QQ 0.002 RR 0.270 SS 132 TT 0.0005 UU 0.0001 VV 0.002 WW 0.009 XX 0.0008 YY 0.0005 ZZ 0.00003 A = (3RS,4RS)-2-[4-(3-Naphthalen-2-ylmethoxy-piperidin-4- yl)-phenoxy]-ethyl thiophene-2-carboxylate hydr°C hloride (Example 58-4) B = (3RS,4RS)-2-[4-(3-Naphthalen-2-ylmethoxy-piperidin-4- yl)-phenoxy]-ethyl 2-chloro-benzoate hydr°C hloride (Example 54-2) C = (3RS,4RS)-2-[4-[3-[4-(2-methoxy-benzyloxy)-naphthalen- 2-ylmethoxy]-piperidin-4-yl]-phenoxy]-ethyl benzoate hydr°C hloride (Example 55-2) D = (3RS,4RS)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3-(2,3- dihydro-benzo[1,4]dioxin-6-ylmethoxy)-piperidine (Example 86- 54) E = (3RS,4RS)-3-(Naphthalen-2-ylmethoxy)-4-[4-(3-phenyl- [1,2,4]oxadiazol-5-ylmethoxy)-phenyl]-piperidine trifluoro- acetate (Example 86-34) F = (3RS,4RS)-3-(Naphthalen-2-ylmethoxy)-4-[4-(3-phenyl- isoxazol-5-ylmethoxy)-phenyl]-piperidine trifluoroacetate (Example 86-36) G = (3RS,4RS)-3-(Naphthalen-2-ylmethoxy)-4-[4-(3- phenylsulphanyl-propyl)-phenyl]-piperidine (Example 86-19) H = (3RS,4RS)-3-[4-[4-[2-(Benzothiazol-2-ylsulphanyl)- ethyl]-phenyl]-piperidin-3-yloxymethyl]-naphthalen-1-ol (Example 86-23) I = (3RS,4RS,5SR)-3-(4-Benzyloxy-naphthalen-2-ylmethoxy)- 4-(4-fluoro-phenyl)-5-propyl-piperidine (Example 64) J = (3SR,4RS,5RS)-4-(4-Benzyloxymethyl-phenyl)-3- methoxymethyl-5-(naphthalen-2-ylmethoxy)-piperidine (Example 86-60) K= (SR)- or (RS)-l-[(3RS,4SR)-4-(4-fluoro-phenyl)-piperidln- 3-yl]-2-naphthalen-2-yl-ethyl benzoate hydr°C hloride (Example 75 b) L= (1RS,2RS,3RS,5SR)-2-(4-Benzyloxy-naphthalen-2- ylmethoxy)-3-(4-fluoro-phenyl)-8-aza-bicyclo[3.2.1 ]°C tane (Example 84 e) M = (3RS,4RS)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3- (naphthalen-2-ylmethoxy)-piperidine N = 4-[2-[7-[(3RS,4RS)-4-[4-(3-Benzyloxy-propoxy)-phenyl]- piperidin-3-yloxymethyl]-naphthalen-2-yloxy]-ethyl]-morpholine hydr°C hloride (1:2) (Example 90-07) 0= Mixture of (RS)- and (SR)-3-[7-[(3RS,4RS)-4-[4-(3- benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]- naphthalen-2-yloxy]-propane-1,2-diol (Example 90-08) P = Mixture of (RS)- and (SR)-3-[2-[7-[(3RS,4RS)-4-[4-(3- benzyloxy-propoxy)-phenyl]-piperidin-3-yIoxymethyl]- naphthalen-2-yloxy]-ethoxy]-propane-1,2-diol hydr°C hloride( 1:1) (Example 98) Q= 1-[2-[7-[(3RS,4RS)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]-naphthalen-2-yloxy]-ethyl]-4-methyl-piperazine hydr°C hloride (1:3) (Example 90-13) R = 1 -[(3RS,4SR)-4-[4-(3-Benzyloxy-propoxy)-phenyl]- piperidin-3-yl]-2-naphthalen-2-yl-ethanone hydr°C hloride (1:1) (Example 100) S = (3RS,4SR,5SR)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3- (1,4-dimethoxy-naphthalen-2-ylmethoxy)-piperidin-5-ol (Example 109-04) T= Mixture of (3RS,4RS)- and (3SR,4SR)-4-[4-(3-benzyloxy- propoxy)-phenyl]-3-[7-[(RS)-2,3-dihydroxy-propoxymethyl]- naphthalen-2-ylmethoxy]-piperidine (Example 106-02) U= Mixture of (3RS,4RS)- and (3SR,4SR)-4-[4-(3-benzyloxy- propoxy)-phenyl]-3-[6-[(RS)-2,3-dihydroxy-propoxymethyl]- naphthalen-2-ylmethoxy]-piperidine (Example 106-01) V = 4-[(3RS,4SR,5SR)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3- (naphthalen-2-ylmethoxy)-piperidin-5-yloxy]-butan-l-ol (Example 110-08) W = 3-[(3RS,4SR,5SR)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3- (naphthalen-2-ylmethoxy)-piperidin-5-yloxy]-propan-l-ol (Example 110-07) X = 1 -{2-[(3RS,4RS,5SR)-4-[4-(3-Benzyloxy-propoxy)- phenyl]-3-(naphthalen-2-ylmethoxy)-piperidin-5-yloxy]-ethyl}- 4-methyl-piperazine (Example 110-02) Y = 4-|2-[(3RS,4RS,5SR)-4-[4-(3-Benzyloxy-propoxy)- phenyl]-3-(naphthalen-2-ylmethoxy)-piperidin-5-yloxy]-ethyl}- morpholine (Example 110-09) Z = (3RS,4SR,5SR)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3-(4- methoxy-benzyloxy)-piperidin-5-ol (Example 109-28) AA = (3R,4s,5S)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3,5-bis- (4-methoxy-benzyloxy)-piperidine (Example 109-27) BB = (3SR,4RS,5RS)-4-[2-[4-[4-(3-Benzyloxy-propoxy)-phenyl]- 5-(naphthalen-2-ylmethoxy)-piperidin-3-ylmethoxy]-ethyl]- morpholine (Example 149-04) CC = (3SR,4RS,5RS)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3- methoxymethyl-5-(naphthalen-2-ylmethoxy)-piperidine (Example 148) DD = (3SR,4RS,5RS)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-5- (naphthaien-2-ylmethoxy)-piperidin-3-ylmethyl [3-(4-methyl- piperazin-1-yl)-propyl]-carbamate (Example 150-01) EE = (3SR,4RS,5RS)-4-[4-[4-(3-Benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3-ylmethylsulphanyl]-pyridine (Example 149-02) FF = 2-(4-Cyclohexyl-butoxy)-5-[(3RS,4RS)-3-(l ,4-dimethoxy-naphthalen-2-ylmethoxy)-piperidin-4-yI]-pyrimidine (Example 139-03) GG = (3'RS,4'RS)-6-(3-Cyclohexyl-propoxy)-3'-(1,4-dimethoxy-naphthalen-2-ylmethoxy)-1',2',3',4',5',6•-hexahydro-[3,4']-bipyridine (Example 140-01) HH = (3SR,4RS,5RS)-[4-[4-(3-Benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3-yl]-methanol hydr°C hloride (Example 149-02) II = (3SR,4RS,5RS)-N-[4-[4-(3-Benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3-ylmethyl]-N,N',N'-trimethyl-ethane-1,2-diamine (Example 149-06) JJ = (3SR,4RS,5RS)-[4-[4-(3-Benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3-ylmethyl]-diethyI-amine (Example 149-05) KK = 1 -[(3RS,4SR,5SR)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-5-(2-morpholin-4-yl-ethoxymethyl)-piperidln-3-yl]-2-naphthalen-2-yl-ethanone (Example 101) LL = (3RS,4RS)-3-(1,4-Dimethoxy-naphthalen-2-ylmethoxy)-4-[4-[3-(2-methoxy-phenoxy)-propoxy]-phenyl]-piperidine (Example 123-27) MM =(3R,4s,5S)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3,5-bis-(3,4,5-trimethoxy-benzyloxy)-piperidine (Example 109-29) NN = (3RS,4RS,5SR)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-5-[1,2,4]triazol-1 -ylmethyl-piperidine hydr°C hloride (Example 149-07) GO = (3RS,4RS)-4-[4-[3-(2-Methoxy-benzyloxy)-propoxy]-phenyl]-3-(quinolin-7-ylmethoxy)-piperidine (Example 120-07) PP = 2-(7-{(3RS,4RS)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl}-naphthalen-2-ylmethoxy)-ethanol (Example 106-03) .= 7-{(3RS,4RS)-4-[4-(3-Benzyloxy-propoxy)-phenyl]-piperidin-3-y loxy methyl }-naphthalen-2-ylmethyl)-dimethyl-amine (Example 106-03) RR = (3R,4R)-3-(4-Benzyloxy-naphthalen-2-ylmethoxy)-4-(4- fluoro-phenyl)-piperidine (Example 154-06) SS = (3S,4S)-3-(4-Benzyloxy-naphthalen-2-ylmethoxy)-4-(4- fluoro-phenyl)-piperidine (Example 154-07) TT = (3'RS,4'RS)-3'-(1,4-Dlmethoxy-naphthalen-2-ylmethoxy)- 6-[3-(2-methoxybenzyloxy)-propoxy]-r,2',3',4',5',6'-hexahydro- [3,4']bipyridine (Example 140.02) UU = (3RS,4RS)-3-(l ,4-Dimethoxy-naphthalen-2-ylmethoxy)-4- [4-[3-(2-methoxy-benzyloxy)-propoxy]-phenyl]-piperidine (Example 123.32) W = (3SR,4RS,5RS)-1 -[4-[4-(3-Benzyloxy-propoxy)-phenyl]-5- (naphthalen-2-ylmethoxy)-piperidin-3-ylmethyl]-imidazolidin-2- one (Example 149,08) WW = (3RS,4RS)-4-[4-[3-(2-Methoxy-benzyloxy)-propoxy]- phenyl]-3-(2-oxo-1,2-dihydro-quinolin-7-ylmethoxy)-pJperidine (Example 120.10) XX = (3RS,4RS)-3-(lsoquinolin-7-ylmethoxy)-4-[4-[3-(2- methoxy-benzyloxy)-propoxy]-phenyl]-piperidine (Example 120.11) YY = (3RS,4RS)-4-[4-[3-(2-Methoxy-benzyloxy)-propoxy]- phenyl]-3-(l ,2,3,4-tetrahydro-quinolin-7-ylmethoxy)-piperidine (Example 120.12) ZZ = (3RS,4SR,5SR)-3-(l ,4-Dimethoxy-naphthalin-2- ylmethoxy)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]-phenyl]- piperidin-5-ol (Example 112-11) The compounds of formula I as well as their pharma-ceutically usable salts can be used as medicaments, e.g. in the form of pharmaceutical preparations. The pharmaceutical preparations can be administered enterally such as orally, e.g. in the form of tablets, coated tablets, dragees, hard and soft gelatine capsules, solutions, emulsions or suspensions, nasally, e.g. in the form of nasal sprays, or rectally, e.g. in the form of suppositories. However, the administration can also be effected parenterally such as intramuscularly or intravenously, e.g. in the form of injection solutions. The compounds of formula I as well as their pharma-ceutically usable salts can be processed with pharmaceutically inert, inorganic or organic excipients for the production of tablets, coated tablets, dragees and hard gelatine capsules. Lactose, corn starch or derivatives thereof, talc, stearic acid or its salts etc can be used e.g. as such excipients for tablets, dragees and hard gelatine capsules. Suitable excipients for soft gelatine capsules are e.g. vegetable oils, waxes, fats, semi-solid and liquid polyols etc. Suitable excipients for the production of solutions and syrups are e.g. water, polyols, sucrose, invert sugar, glucose etc. Suitable excipients for injection solutions are e.g. water, alcohols, polyols, glycerol, vegetable oils bile acids, lecithin etc. Suitable excipients for suppositories are e.g. natural or hardened oils, waxes, fats, semi-liquid or liquid polyols etc. Moreover, the pharmaceutical preparations can contain preservatives, solubilizers, viscosity-increasing substances, stabilizers, wetting agents, emulsifiers, sweeteners, colorants, flavorants, salts for varying the osmotic pressure, buffers, masking agents or antioxidants. They can also contain still other thereapeutically valuable substances. n accordance with the invention the compounds of general formula I as well as their pharmaceutically usable salts can be used in the control or prevention of high blood pressure and cardiac insufficiency, as well as glaucoma, cardiac infarct, kidney insufficiency and restenosis. The compounds in accordance with the invention can also be administered in combination with one or more agents having cardiovascular activity, e.g. a- and p-bl°C kers such as phentol- amine, phenoxybenzamine, prazosin, terazosin, tolazine, atenolol, metoprolol, nadolol, propranolol, timolol, carteolol etc.; vaso- dilators such as hydralazine, minoxidil, diazoxide, nitroprusside, flosequinan etc.; calcium antagonists such as amrinone, bencyclane, diltiazem, fendiline, flunarizine, nicardipine, nimodipine, perhexilene, verapamil, gallopamil, nifedipine etc.; ACE inhibitors such as cilazapril, captopril, enalapril, lisinopril etc.; potassium activators such as pinacidil; anti-serotoninergics such as ketanserin; thromboxane synthetase inhibitors; angio¬tensin II antagonists; as well as diuretics such as hydroc hloro¬thiazide, chlorothiazide, acetazolamide, amiloride, bumetanide, benzthiazide, ethacrynic acid, furosemide, indacrinone, metolazone, spironolactone, triamterene, chlorthalidone etc.; sympatholytics such as methyldopa, clonidine, guanabenz, reserpine; and other agents which are suitable for the treatment of high blood pressure, cardiac insufficiency or vascular disorders in humans and animals assoc iated with diabetes or kidney disorders such as acute or chronic kidney failure. Such combinations can be used separately or in preparations which contain several components. The dosage can vary within wide limits and will, of course, be fitted to the individual requirements in each particular case. In general, in the case of oral administration a daily dosage of about 3 mg to about 3 g, preferably about 10 mg to about 1 g, e.g. approximately 300 mg per adult person (70 kg), divided into preferably 1-3 individual doses which e.g. can be of equal amount, should be sufficient, although the upper limit given can also be exceeded when this is found to be indicated. Usually, children receive a reduced dose appropriate to their age and body weight. The following Examples are intended to illustrate the present invention, but they are not intended to be limiting in any manner. All temperatures are given in degrees Celsius. The following abbreviations are used: B°C DME DMF tert-Butoxycarbonyl 1,2-Dimethoxyethane Dimethylformamide TBAF : Tetrabutyiammonium fluoride EDC: N-Ethyl-N'-(3-dimethylaminopropyl)-carbodiimide hydroc hloride THP: Tetrahydropyranyl TR°C : Trichloroethoxycarbonyl. Ik. ■! TPTU: 0-( 1,2-Dihydr0-2-oxo-1 -pyridyl)-N,N,N N tetramethyluronium-tetrafluoroborate >!■. il HBTU: 0-(1 H-Benzotriazol-1 -yl)-N,N,N N - tetramethyluronium-hexafluorophosphate SEM: 2-(Trimethylsilyl)-ethoxymethyl Example 1 (a) A solution of 23.6 g (100 mmol) of 1,3-dibromobenzene in 250 ml of absolute ether was cooled to -75°C . A solution of 62.5 ml (100 mmol) of n-butyllithium (1.6M in hexane) was added dropwise within 45 minutes. The resulting suspension was stirred at -75°C for 2.5 hours. Subsequently, a solution of 19.0 g (100 mmol) of 1-benzyl-4-piperidone in 100 ml of absolute ether was added dropwise within 30 minutes at -70°C to -75°C and thereafter the mixture was stirred for 2 hours. Subsequently, the mixture was partitioned between ether and saturated ammonium chloride solution, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product was purified by chromatography on silica gel with a 1:1 mixture of methylene chloride and hexane as the eluent. There were obtained 28.3 g (82% of theory) of 1-benzyl-4-(3-bromophenyl)-piperidin-4-ol as a yellow oil; MS: 345, 347 (M)+. (b) A solution of 28.2 g (81.4 mmol) of 4-(3-bromophenyl)- piperidin-4-ol in 600 ml of toluene was treated with 30 g (157 mmol) of p-toluenesulphonic acid monohydrate and heated to reflux on a water separator for 4 hours. Subsequently, the reaction mixture was cooled to room temperature and adjusted to pH 10 with 3N sodium hydroxide solution. Thereafter, it was firstly extracted three times with 500 ml of methylene chloride. The combined organic phases were washed three times with 200 ml of water each time, dried over magnesium sulphate and then evaporated under reduced pressure. The crude product was purified by chromatography on silica gel with a 1:1 mixture of methylene chloride and hexane as the eluent. There were obtained 9.5 g (36% of theory) of 1-benzyl-4-(3-bromophenyl)-1,2,3,6-tetrahydro-pyridine as a light yellow oil; MS: 327, 329 (M+H)+. (c) 3.15 g (83.3 mmol) of sodium borohydride were added portionwise at room temperature to a suspension of 9.5 g (28.9 mmol) of l-benzyl-4-(3-bromophenyl)-l,2,3,6-tetrahydro-pyridine in 65 ml of absolute dimethoxyethane (DME). Thereafter, a solution of 17.7 ml (20.0 g 140.9 mmol) of boron trifluoride etherate in 11 ml of DME was added dropwise at 15-20°C and the mixture was stirred at room temperature for 2 hours. Sub¬sequently, a solution of 18.3 g (326 mmol) of potassium hydroxide in 100 ml of water was added dropwise within 30 minutes at 20-25°C. Finally, 55 ml of 30% hydrogen peroxide solution were added dropwise within 30 minutes at 20-25°C . The mixture was stirred at room temperature for 30 minutes and heated to reflux for 3 hours. After cooling the reaction mixture the separated boric acid was filtered off. Subsequently, the filtrate was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and the solvent was removed under reduced pressure. The crude product was purified by chromatography on silica gel with a 1:1 mixture of ethyl acetate and methylene chloride as the eluent. There were obtained 6.3 g (63% of theory) of (3RS,4RS)-l-benzyl-4-(3-bromophenyl)-piperidin-3-ol as a colourless oil. MS: 345, 347 (M)+. (d) A solution of 691 mg (2.00 mmol) of (3RS,4RS)-1-benzyl-4- (3-bromophenyl)-piperidin-3-ol in 3 ml of absolute tetrahydro- furan was treated with 163 mg (2.20 mmol) of lithium carbonate and cooled to -50°C . A solution of 722 mg (4.00 mmol) of p- trimethylsilylethyl chloroformate [Synthesis 346 (1987)] in 4 ml of toluene was added dropwise thereto at -50°C . The reaction mixture was warmed to room temperature ana stirred for 24 hours. Subsequently, the mixture was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (0.8 g) was purified by chromatography on silica gel with methylene chloride as the eluent. There were obtained 470 mg (43% of theory) of 2-trimethylsilylethyl (3RS,4RS)-4-(3-bromophenyl)-3-(2-trimethylsilyl-ethoxycarbonyloxy)-piperidine-1-carboxylate as a light yellow oil, which was used directly in the next step. (e) A solution of 470 mg (0.863 mmol) of 2-trimethylsilylethyl (3RS,4RS)-4-(3-bromophenyl)-3-(2-trimethylsilyl-ethoxy-carbonyloxy)-piperidine-1-carboxylate in 3 ml of absolute tetrahydrofuran was treated with 2.65 ml (2.91 mmol) of tetrabutylammonium fluoride solution (1.1M in THF) and stirred at room temperature for 2.5 hours. Subsequently, the mixture was partitioned between methylene chloride and saturated sodium carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (440 mg) was purified by chroma¬tography on silica gel with a 6.5:1:0.1 mixture of methylene chloride, MeOH and 25% ammonia as the eluent. There were obtained 180 mg (81% of theory) of (3RS,4RS)-4-(3-bromo-phenyl)-piperidin-3-ol as a light yellow oil. MS: 255, 257 (M)+. (f) A solution of 180 mg (0.702 mmol) of (3RS,4RS)-4-(3-bromophenyl)-piperidin-3-ol in 1 ml of absolute dimethyl-formamide was treated at 0 °Cwith 0.1 ml (73 mg, 0.72 mmol) of triethylamine. A solution of 167 mg (76.5 mmol) of di-tert-butyl dicarbonate in 0.5 ml of dimethylformamide was added thereto at 0°C . The mixture was warmed to room temperature and stirred for 20 hours. The solvent was distilled off at 50-55°C at 0.1 mm Hg. Subsequently, the residue obtained was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product was purified by chromatography on silica gel with a 4:1 mixture of methylene chloride and ethyl acetate. There were obtained ZZO mg (92% or theory) of tert-butyl (3RS,4RS)-4-(3-bromophenyl)-3-hydroxy-piperidine-1-carboxylate as a colourless solid; MS: 299, 301 (M-C4H8)+. (g) A solution of 168 mg (0.47 mmol) of tert-butyl (3RS,4RS)-4-(3-bromophenyl)-3-hydroxy-piperidine-1 -carboxylate and 157 mg (0.71 mmol) of 2-bromomethylnaphthalene in 2 ml of dimethylformamide was treated with 28 mg (0.7 mmol) of sodium hydride (60% dispersion in refined oil) and the mixture was stirred at room temperature for 3 hours. Subsequently, the reaction mixture was partitioned between ethyl acetate and water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product was purified by chromatography on silica gel with a 1:4 mixture of ethyl acetate and hexane as the eluent. There were obtained 173 mg (74% of theory) of tert-butyl (3RS,4RS)-4-(3-bromophenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow oil; MS: 439, 441 (M-C4H8)+. (h) A solution of 173 mg (0.35 mmol) of tert-butyl (3RS,4RS)-4-(3-bromophenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate in 6 ml of methanol was treated with 6 ml of a 2N solution of hydrogen chloride in MeOH and stirred at 50°C for 4 hours. Subsequently, the mixture was partitioned between ethyl acetate and a 5% sodium hydrogen carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product was purified by chromatography on silica gel with a 10:1:0.1 mixture of methylene chloride, MeOH and 25% ammonia and the eluent. There were obtained 126 mg (91% of theory) of (3RS,4RS)-4-(3-bromophenyl)-3-(naphthalen-2-ylmethoxy)-piperidine as a light yellow oil. MS: 396, 398 (M+H)+. Example 2 The following compounds were obtained by cleavage of the B°C group in an analogous manner to that described in Example 1 (h): 1) - (3RS,4RS)-3-(4-Methoxy-benzyloxy)-4-phenyl-piperidine as a light yellow oil, MS: 298 (M+H)+, from tert-butyl (3RS,4RS)-3-(4-methoxy-benzyloxy)-4-phenyl-piperidine-1-carboxylate; 2) - (3RS,4RS)-4-(4-bromophenyl-3-(4-methoxy-benzyloxy)-piperidine as a colourless oil, MS: 376, 378 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-bromophenyl-3-(4-methoxy-benzyloxy)-piperidine-1 -carboxylate; 3) - (3RS,4RS)-3-(4-methoxy-benzyloxy)-4-(3-trifluoro-methylphenyl)-piperidine as a colourless oil, MS: 366 (M+H)+, from tert-butyl (3RS,4RS)-3-(4-methoxy-benzyloxy)-4-(3-trifluoromethylphenyl)-piperidine-l-carboxylate; 4) - (3RS,4RS)-3-(4-methoxy-benzyloxy)-4-p-tolyl-piperidine as a colourless solid, MS: 312 (M+H)+, from tert-butyl (3RS,4RS)-3-(4-methoxy-benzyloxy)-4-p-tolyl-piperidine-1-carboxylate; 5) - (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-phenyl-piperidine as a light yellow oil, MS: 318 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-phenyl-piperidine-1-carboxylate; 6) - (3RS,4RS)-4-(4-bromophenyl)-3-(naphthalen-2-yl-methoxy)-piperidine as a colourless solid, MS: 396, 398 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-bromophenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate; 7) - (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-(3-trifluoro-methyl-phenyl)-piperidine as a colourless oil, MS: 386 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-(3-trifluoromethyl-phenyl)-piperidine-1-carboxylate; 8) - (3RS,4RS)-4-cyclohexyl-3-(naphthaien-2-ylmethoxy)- piperidine as a light yellow oil, MS: 324 (M+H)+, from tert-butyl (3RS,4RS)-4-cyclohexyl-3-(naphthalen-2-ylmethoxy)-piperidine- 1-carboxylate; 9) - (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-p-tolyl- piperidine as a colourless solid, MS: 332 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-p-tolyl-piperidine-1- carboxylate; 10) - (3RS,4RS)-4-naphthalen-2-yl-3-(naphthalen-2-yl-methoxy)-piperidine as a colourless oil, MS: 367 (M)+, from tert-butyl (3RS,4RS)-4-naphthalen-2-yl-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate; 11) - (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-(5,6,7,8-tetrahydro-naphthalen-2-yl)-piperidine as a colourless oil, MS: 372 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-(5,6,7,8-tetrahydro-naphthalen-2-yl)-piperidine-1-carboxylate; 12) - (3RS,4RS)-4-naphthalen-1-yl-3-(naphthalen-2-yl-methoxy)-piperidine as a colourless solid, MS: 367 (M)+, from tert-butyl (3RS,4RS)-4-naphthalen-1 -yl-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 13) - (3RS,4RS)-4-(3,4-olourless resin, MS: 37dimethoxy-phenyl)-3-(naphthalen-2-yl methoxy)-piperidine as a c7 (M)+, from tert-butyl (3RS,4RS)-4-(3,4-dimethoxy-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 14) - (3RS,4RS)-4-acenaphthen-5-yl-3-(naphthalen-2-yl-methoxy)-piperidine as a colourless solid, MS: 394 (M+H)+, from tert-butyl (3RS,4RS)-4-acenaphthen-5-yl-3-(naphthalen-2-yImethoxy)-piperidine-1-carboxylate; 15) - (3RS,4RS)-4-(4-chlorophenyl)-3-(3-phenoxy-benzyloxy)-piperidine as a colourless solid, MS: 394, 396 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-chlorophenyl)-3-(3-phenoxy-ben2yloxy)-piperidine-1 -carboxylate; 16) - (3RS,4SR)-3-(naphthalen-2-ylmethoxy)-4-phenyl-piperidine hydroc hloride as a colourless powder, MS: 318 (M+H)+, from tert-butyl (3RS,4SR)-3-(naphthalen-2-ylmethoxy)-4-phenyl-piperidine-1-carboxylate. The B°C compounds used as the starting materials were prepared as follows: The following compounds were obtained in an analogous manner to that described in Example 1 (b)-(c) and (f)-(g): (a) From 4-phenyl-piperidin-4-ol there was obtained by elimination 4-phenyl-1,2,3,6-tetrahydro-pyridine as a light yellow oil; MS: 159 (M)+. Subsequent hydroboration gave (3RS,4RS)-4-phenyl-piperidin-3-ol as a colourless solid; MS: 177 (M)+. Introduction of the B°C group yielded tert-butyl (3RS,4RS)-3-hydroxy-4-phenyl-piperidine-1-carboxylate as a colourless solid; MS: 277 (M)+. After alkylation with 4-methoxybenzyl bromide there was obtained tert-butyl (3RS,4RS)-3-(4-methoxy-ben2yloxy)-4-phenyl-piperidine-1-carboxylate as a colourless solid; MS: 340 (M-C4H9)+. (b) From 4-(4-bromophenyl)-piperidin-4-ol there was obtained by elimination 4-(4-bromophenyl)-1,2,3,6-tetrahydro-pyridine as a light yellow solid; MS: 237, 239 (M)+. Subsequent hydroboration gave (3RS,4RS)-4-(4-bromophenyl)-piperidin-3-ol as a colourless solid; MS: 255, 257 (M)+. Introduction of the B°C group yielded tert-butyl (3RS,4RS)-4-(4-bromophenyl)-3-hydroxy-piperidine- 1-carboxylate as a colourless solid; MS: 299, 301 (M-C4H8)+. After alkylation with 4-methoxybenzyl bromide there was obtained tert-butyl (3RS,4RS)-4-(4-bromophenyl)-3-(4-methoxy-benzyloxy)-piperidine-1-carboxylate as a light yellow oil; MS: 418, 420 (M-C4H9)+. (c) From 4-(3-trifluoromethylphenyl)-piperidin-4-ol there was obtained by elimination 4-(3-trifluoromethylphenyl)-l ,2,3,6-tetrahydro-pyridine as a colourless solid; MS: 227 (M)+. Subse¬quent hydroboration gave (3RS,4RS)-4-(3-trifluoromethylphenyl)-piperidin-3-ol as a colourless solid; MS: 245 (M)+, Introduction of the B°C group yielded tert-butyl (3RS,4RS)-3-hydroxy-4-(3-trifluoromethylphenyl)-piperidine-1-carboxylate as a colourless solid; MS: 289 (M-C4H8)+. After alkylation with 4-methoxybenzyl bromide there was obtained tert-butyl (3RS,4RS)-3-(4-methoxy-benzyloxy)-4-(3-trifluoromethylphenyl)-piperidine-1-carboxy-late as a light yellow oil; MS: 408 (M-C4H9)+. (d) From 1-benzyl-4-(p-tolyl)-piperidin-4-ol there was obtained by elimination 1-benzyl-4-(p-tolyl)-1,2,3,6-tetrahydro-pyridine as a light yellow solid; MS: 263 (M)+. Subsequent hydro¬boration gave (3RS,4RS)-1-benzyl-4-(p-tolyl)-piperidin-3-ol as a colourless solid; MS: 281 (M)+. (e) A solution of 2.5 g (8.9 mmol) of (3RS,4RS)-1-benzyl-4-(p-tolyl)-piperidin-3-ol in 100 ml of methanol was hydrogenated at 5 bar at room temperature for 18 hours using a palladium (10%)-carbon catalyst. For the working up, the catalyst was filtered off, washed with methanol and the solution obtained was evaporated under reduced pressure. For purification, the residue was chro-matographed on silica gel using a 5:1:0.1 mixture of methylene chloride, methanol and ammonia as the eluent. There were obtained 1.15 g (68% of theory) of (3RS,4RS)-4-(p-tolyl)-piperidin-3-ol as a colourless solid; MS: 191 (M)+. (f) From (3RS,4RS)-4-(p-tolyl)-piperidin-3-ol by introduction of the B°C group there was obtained tert-butyl (3RS,4RS)-3-hydroxy-4-(p-tolyl)-piperidine-1-carboxylate as a colourless solid; MS: 291 (M)+. After alkylation [with] 4-methoxybenzyl bromide there was obtained tert-butyl (3RS,4RS)-3-(4-methoxy-benzyloxy)-4-(p-tolyl)-piperidine-1-carboxylate as a colourless oil; MS: 354 (M-C4H9)+. The following compounds were obtained in an analogous manner to that described in Example 1 (g): (g) By alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-phenyl-piperidine-1-carboxylate with 2-bromomethylnaphthalene there was obtained tert-butyl (3RS,4RS)-3-(napththalen-2-ylmethoxy)-4-phenyl-piperidine-l-carboxylate as a light yellow oil; MS: 417 (M)+. (h) By alkylating tert-butyl (3RS,4RS)-4-(4-bromophenyl)-3-hydroxy-piperidine-1-carboxylate with 2-bromomethyl¬naphthalene there was obtained tert-butyl (3RS,4RS)-4-(4-bromophenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless solid; MS: 495, 497 (M)+. (i) By alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-(3-trifluoromethylphenyl)-piperidine-l -carboxylate with 2-bromomethylnaphthalene there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-(3-trifluoromethyl-phenyl)-piperidine-l-carboxylate as a light yellow oil; MS: 485 (M)+. (j) A solution of 4.0 g tert-butyl (13.8 mmol) of tert-butyl (3RS,4RS)-3-hydroxy-4-phenyl-piperidine-l -carboxylate in 100 ml of methanol was hydrogenated at 150 bar at 100°C for 18 hours using a rhodium(5%)-aluminium oxide catalyst. For the working up, the catalyst was filtered off, washed with methanol and the solution obtained was evaporated under reduced pressure. For purification, the residue was chromatographed on silica gel using a 4:1 mixture of hexane and ethyl acetate as the eluent. There were obtained 2.32 g (59% of theory) of tert-butyl (3RS,4RS)-4-cyclohexyl-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless solid; MS: 283 (M)+. (k) By alkylating tert-butyl (3RS,4RS)-4-cyclohexyl-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate with 2-bromomethylnaphthalene there was obtained tert-butyl (3RS,4RS)-4-cyclohexyl-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow oil; MS: 423 (M)+. (I) By alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-(p-tolyl)-piperidine-1-carboxylate with 2-bromomethylnaphthalene there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-p-tolyl-piperidine-1-carboxylate as a colourless oil; MS: 431 (M)+ The remaining starting materials were obtained as follows: (m) From 2-bromonaphthalene and 1-benzyl-4-piperidone there was obtained in an analogous manner to Example 1 (a) 1 -benzyl-4-naphthalen-2-yl-piperidin-4-ol as a light yellow oil; MS: 317 (M)+. Elimination in an analogous manner to that described in Example 1(b) yielded 1-benzyl-4-naphthalen-2-yl-1,2,3,6-tetrahydro-pyridine as a light brown oil; MS: 299 (M)+. Subse¬quent cleavage of the benzyl group analogously to Example 1 (d) gave 2-trimethylsilylethyl 4-naphthalen-2-yl-1,2,3,6-tetra-hydro-pyridine-1-carboxylate as a colourless solid; 4-MS: 325 (M-C2H4)+. By treatment with tetrabutylammonium fluoride in tetrahydrofuran analogously to Example 1 (e) there was obtained 4-naphthalen-2-yl-1,2,3,6-tetrahydro-pyridine as a colourless solid; MS: 209 (M)+. Subsequent hydroboration in an analogous manner to that described in Example 1 (c) gave (3RS,4RS)-naphthalen-2-yl-4-piperidin-3-ol as a colourless solid; MS: 227 (M)+. Introduction of the B°C group in analogy to Example 1 (f) yielded tert-butyl (3RS,4RS)-3-hydroxy-4-naphthalen-2-yl-piperidine-1-carboxylate as a colourless oil; MS: 327 (M)+. After alkylation with 2-bromomethylnaphthalene in an analogous manner to the procedure described in Example 1 (g) there was obtained tert-butyl (3RS,4RS)-4-naphthalen-2-yl-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil; MS: 467 (M)+. (n) In an analogous manner to that described in Example 2(e), by catalytically hydrogenating (3RS,4RS)-1-benzyl-4-naphthalen-2-yl-piperidin-3-ol there was obtained (3RS,4RS)-4-(5,6,7,8- tetrahydro-naphthalen-2-yl)-piperidin-3-ol as a colourless solid; MS: 231 (M)+. Introduction of the B°C group in an analogous manner to that described in Example 1 (f) yielded tert-butyl (3RS,4RS)-3-hydroxy-4-(5,6,7,8-tetrahydro-naphthalen-2-yl)-piperidine-1-carboxylate as a colourless oil; MS: 331 (M)+. After alkylation with 2-bromomethylnaphthalene in an analogous manner to the procedure described in Example 1 (g) there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-(5,6,7,8-tetrahydro-naphthalen-2-yl)-piperidine-1-carboxylate as a colourless oil; MS: 471 (M)+. (o) From 1-benzyl-4-naphthalen-1-yl-1,2,3,6-tetrahydro-pyridlne (EP-A-372 776) by hydroboration in an analogous manner to Example 1(c) there was obtained (3RS,4RS)-1-benzyl-4-naphthalen-1-yl-piperidin-3-ol as a colourless solid; MS: 317 (M)+. The benzyl group was removed by catalytic hydrogenation [palladium (10%)-charcoal, ethanol, 80°C , 24 hours, 50 bar, 21% of theory] in an analogous manner to that described in Example 2(e). (3RS,4RS)-4-Naphthalen-1-yl-piperidin-3-ol was obtained as a beige solid; MS: 227 (M)+. Introduction of the B°C group in an analogous manner to that described in Example 1 (f) yielded tert-butyl (3RS,4RS)-3-hydroxy-4-naphthalen-1 -yl-piperidine-1 -carboxylate as a colourless solid; MS: 327 (M)+. After alkylation with 2-bromomethylnaphthalene, in analogy to the procedure described in Example 1 (g) there was obtained tert-butyl (3RS,4RS)-4-naphthalen-1-yl-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless solid; MS: 467 (M)+. (p) From 1-benzyl-4-(3,4-dimethoxy-phenyl)-1,2,3,6-tetrahydro-pyridine (JP 60 146 872) by hydroboration in an analogous manner to that described in Example 1 (c) there was obtained (3RS,4RS)-1 -benzyl-(3,4-dimethoxy-phenyl)-piperidin-3-ol as a colourless solid; MS: 327 (M)+, The benzyl group was removed by catalytic hydrogenation [palladium (10%)-charcoal, methanol, room temperature, 18 hours, 5 bar, 81% of theory] in an analogous manner to that described in Example 2(e). (3RS,4RS)-4-(3,4-Dimethoxy-phenyl)-piperidin-3-ol was obtained as a colourless solid; MS: 237 (M)+. Introduction of the B°C group in an analogous manner to that described in Example 1(f) yielded tert-butyl (3RS,4RS)-3-hydroxy-4-(3,4-dimethoxy-phenyl)-piperidine-1-carboxylate as a light yellow oil; MS: 337 (M)+. After alkylation with 2-bromomethylnaphthalene in analogy to the procedure described in Example 1 (g) there was obtained tert-butyl (3RS,4RS)-4-(3,4-dimethoxy-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow oil; MS: 477 (M)+ (q) From 5-bromo-acenaphthene and 1-benzyl-4-piperidone there was obtained in an analogous manner to Example 1 (a) 4-acenaphthen-5-yl-1-benzyl-piperidin-4-ol as a yellow oil; MS: 343 (M)+. Elimination in an analogous manner to that described in Example 1(b) yielded 4-acenaphthen-5-yl-1-ben2yl-1,2,3,6-tetrahydro-pyridine as a light brown oil; MS: 325 (M)+. Subsequent hydroboration in an analogous manner to that described in Example 1(c) gave (3RS,4RS)-l-benzyl-acenaphthen-5-yl-4-piperidin-3-ol as a yellow oil; MS: 343 (M)+. The benzyl group was removed by catalytic hydrogenation [palladium (10%)-charcoal, methanol, room temperature, 18 hours, 5 bar, 95% of theory] in an analogous manner to that described in Example 2(e). (3RS,4RS)-4-Acenaphthen-5-yl-piperidin-3-ol was obtained as a colourless solid; MS: 253 (M)+. Introduction of the B°C group in an analogous manner to that described in Example 1 (f) yielded tert-butyl (3RS,4RS)-4-acenaphthen-5-yl-3-hydroxy-piperidine-1-carboxylate as a colourless solid; MS: 353 (M)+. After alkylation with 2-bromomethylnaphthalene in analogy to the procedure described in Example 1(g) there was obtained tert-butyl (3RS,4RS)-4-acenaphthen-5-yl-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate as a yellow solid; MS: 493 (M)+. (r) From 4-(4-chlorophenyl)-piperidin-4-ol by elimination in an analogous manner to that described in Example 1 (b) there was obtained 4-(4-chlorophenyl)-1,2,3,6-tetrahydro-pyridine as a light yellow solid; MS: 1 93, 195 (M)+. Hydroboration in an analogous manner as Example 1 (c) gave (3RS,4RS)-4-(4-chloro-phenyl)-piperidin-3-ol as a colourless solid; MS: 211, 213 (M)+. Introduction of the B°C group in an analogous manner to that described in Example 1(f) yielded tert-butyl (3RS,4RS)-4-(4-chlorophenyl)-3-hydroxy-piperidine-1-carboxylate as a colourless solid; MS: 255, 257 (M-C4H8)+=. After alkylation with 4-phenoxybenzyl chloride in analogy to the procedure described in Example 1 (g) there was obtained tert-butyl (3RS,4RS)-4-(4-chlorophenyl)-3-(4-phenoxy-benzyloxy)-piperidine-1-carboxylate as a colourless oil; MS: 437, 439 (M-C4H9)+. (s) From (3RS,4SR)-4-phenyl-piperidin-3-ol [J.A.Gauthier et al., US 4132710] by introduction of the B°C group there was obtained tert-butyl (3RS,4SR)-3-hydroxy-4-phenyl-piperidine-1-carboxylate as a colourless solid; m.p.: 134-134.5°C. Subsequent alkylation with 2-bromomethylnaphthalene gave tert-butyl (3RS,4SR)-3-(naphthalen-2-ylmethoxy)-4-phenyi-piperidine-1-carboxylate as a colourless solid; MS: 417 (M)+. Example 3 130 mg (0.31 mmol) of tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-methoxy-benzyloxy)-piperidine-1-carboxylate were dissolved in 5 ml of methanol, treated with 5 ml of a 2N solution of hydrogen chloride in methanol and stirred at 50°Cfor 4 hours. Subsequently, the mixture was partitioned between ethyl acetate and aqueous 5% sodium hydrogen carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was distilled off under reduced pressure. For purification, the crude product was chromatographed on silica gel with a 10:1:0.1 mixture of methylene chloride, methanol and ammonia as the eluent. There were obtained 76 mg (78% of theory) of (3RS,4RS)-4-(4-fluoro-phenyl)-3-(4-methoxy-benzyloxy)-piperidine as a colourless oil. MS:316(M+H)+. The tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-methoxy-benzyloxy)-piperidine-1-carboxylate used as the starting material was prepared as follows: (a) 20.0g (93.6mmol) of (3Rs,4Rs)-4-(4-fluorophenyl)-1,2,3,6-tetrahydropyridine hydroc hloride were suspended in 160 ml of absolute dimethoxyethane. 10.6 g (280 mmol) of sodium borohydride were added portionwise at room temperature. Thereafter, a solution of 62 ml (500 mmol) of boron trifluoride etherate in 30 ml of dimethoxyethane was added dropwise at 1 5-20°C and the mixture was stirred at room temperature for 2.5 hours. Subsequently, a solution of 65 g (1.16 mmol) of potassium hydroxide in 340 ml of water was added dropwise at 20-25°C within 60 minutes. 55 ml of hydrogen peroxide solution (30%) were then added dropwise at 20-25°C within 30 minutes. The mixture was stirred at room temperature for 30 minutes and boiled under reflux for 3 hours. After cooling the reaction mixture the precipitated boric acid was filtered off. Subse¬quently, the filtrate was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and the solvent was distilled off under reduced pressure. The crude product was purified by chromatography on silica gel with a 3:1:0.1 mixture of methylene chloride, methanol and ammonia as the eluent. There were obtained 9.1 g (50% of theory) of (3RS,4RS)-4-(4-fluorophenyl)-piperidin-3-ol as a colourless oil. MS: 195 (M)+. (b) 4.10 g (21.0 mmol) of (3RS,4RS)-4-(4-fluorophenyl)-piperidin-3-ol were dissolved in 35 ml of absolute dimethyl-formamide. Thereto there were added at 0°C 3.2 ml (23.0 mmol) of triethylamine and subsequently dropwise a solution of 5.04 g (23.1 mmol) of di-tert-butyl dicarbonate in 15 ml of dimethyl-formamide. The mixture was warmed to room temperature and stirred for 20 hours. The solvent was distilled off at 0.1 mm Hg at 50-55°C. Subsequently, the residue obtained was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (7.09 g) was purified by chromatography on silica gel with a 2:3 mixture of ethyl acetate and hexane as the eluent. There were obtained 5.45 mg (88% of theory) of tert-butyl (3RS,4RS)-4-(4-fluoro- phenyl)-3-hydroxy-piperidine-1-carboxylate; MS: 239 (M - C4H8)+. (c) 200 mg (0.68 mmol) of tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-1-carboxylate and 159 mg (1.01 mmol) of 4-methoxybenzyl chloride were dissolved in 3 ml of dimethylformamide. 40 mg (1.01 mmol) of a 60% sodium hydride suspension were added and the mixture was stirred at room temperature for 3 hours. Subsequently, the reaction mixture was partitioned between ethyl acetate and water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product was purified by chromatography on silica gel with a 1:3 mixture of ethyl acetate and hexane as the eluent. There were obtained 250 mg (90% of theory) of tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-methoxy-benzyloxy)-piperidine-1-carboxylate as a light yellow oil; MS: 358 (M - C41-19)+. Example 4 The following compounds were prepared in an analogous manner to that described in Example 3: 1) (3RS,4RS)-4-(4-fluorophenyl)-3-(naphthalen-2-yl-methoxy)-piperidine as a colourless oil, MS: 336 (M+1)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate; 2) (3RS,4RS)-3-(3-benzyloxy-benzyloxy)-4-(4-fluorophenyl)-piperidine as a colourless solid, MS: 392 (M+1)+, from tert-butyl (3RS,4RS)-3-(3-benzyloxy-benzyloxy)-4-(4-fluorophenyl)-piperidine-1 -carboxylate; 3) (3RS,4RS)-4-(4-fluorophenyl)-3-(4-methoxy-quinazolin-2 ylmethoxy)-piperidine as a colourless solid, MS: 368 (M+1)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-methoxy-quinazolin-2-ylmethoxy)-piperidine-1-carboxylate; 4) (3RS,4RS)-3-(benzo[b]thiophen-5-ylmethoxy)-4-(4-fluoro-phenyl)-piperidine as a colourless solid, MS: 342 (M+1)+, from tert-butyl (3RS,4RS)-3-(benzo[b]thiophen-5-ylmethoxy)-4-(4-fluoro-phenyl)-piperidine-l-carboxylate; 5) (3RS,4RS)-4-(4-fluorophenyl)-3-(indan-5-ylmethoxy)-piperidine as a colourless solid, MS: 326 (M+1)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(indan-5-yl-methoxy)-piperidine-1 -carboxylate, 6) (3RS,4RS)-4-(4-fluoro-phenyl)-3-(5,6,7,8-tetrahydro-naphthalen-2-ylmethoxy)-piperidine as a colourless solid, MS: 340 (M+1)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(5,6,7,8-tetra-hydronaphthalen-2-ylmethoxy)-piperidine-l-carboxylate; 7) (3RS,4RS)-4-(4-fluoro-phenyl)-3-(isoquinolin-6-yl- methoxy)-piperidine as a colourless solid, MS: 337 (M+1)+, from tert-butyl (3RS,4RS)-4-(4-fluoro-phenyl)-3-(isoquinolin-6-yl- methoxy)-piperidine-1-carboxylate. The B°C derivatives used as the starting materials were obtained as follows in an analogous manner to the alkylation procedure described in Example 3 (c): - tert-Butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate as a light yellow oil, MS: 436 (M+1)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-1-carboxylate and 2-naphthylmethyl bromide; - tert-butyl (3RS,4RS)-3-(3-benzyloxy-benzyloxy)-4-(4-fluoro-phenyl)-piperidine-l-carboxylate as a colourless solid, MS: 492 (M+1)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-1-carboxylate and 3-benzyloxy-benzyl chloride [J. Med. Chem. 31(3), 606 (1988)]; - tert-butyl (3RS,4RS)-4-(4-tluorophenyl)-:5-(.4-metnoxy-quinazolin-2-ylmethoxy)-piperidine-l-carboxylate as a colour¬less solid, MS: 492 (M+l)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-l-carboxylate and 2-bromo-methyl-4-methoxy-quinazoline; - tert-butyl (3RS,4RS)-3-(benzo[b]thiophen-5-ylmethoxy)-4-(4-fluoro-phenyl)-piperidine-l-carboxylate as a light yellow resin, MS: 442 (M+l)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-1-carboxylate and 5-bromomethyl-benzo[b]-thiophene [J. Med. Chem. 34(1), 65(1991)]; - tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(indan-5-yl-methoxy)-piperidine-l-carboxylate as a colourless solid, MS: 426 (M+1)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-1-carboxylate and 5-chloromethylindane [Red. Trav. Chim. Pays-Bas ZZ, 792 (1988)]; - tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-(5,6,7,8-tetra-hydro-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate as a light yellow resin, MS: 440 (M+l)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-l -carboxylate and 6-chloromethyl-l,2,3,4-tetrahydro-naphthalene [J. Chem. S°C . 684(1941)]; - tert-butyl (3RS,4RS)-4-(4-fluoro-phenyl)-3-(isoquinolin-6-ylmethoxy)-piperidine-l-carboxylate as a light yellow resin, MS: 437 (M+l)+, from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-l-carboxylate and 6-bromomethyliso-quinollne hydrobromide. 2-Bromomethyl-4-methoxy-quinazoline (a) By brominating 2-methyl-4-methoxy-quinazoline [Recl. Trav. Chim. Pays-Bas 76, 401 (1957)] with N-bromosuccinimide in carbon tetrachloride in an analogous manner to the procedure described for the preparation of 6-bromomethylquinoxaline [J. Het. Chem. 11, 595(1974)] from 6-methylquinoxaline there was obtained 2-bromomethyl-4-methoxy-quinazoline as a light yellow solid; MS: 252, 254 (M)+. 6-Bromomethyl-isoquinoline hydrobromide (b) From isoquinoline-6-carboxylic acid [J.Am.Chem.S°C . 61, 183(1939)] by esterification with ethanol/sulphuric acid there was obtained ethyl isoquinoline-6-carboxylate as a colourless solid; MS: 201 (M)+. Subsequent reduction yielded 6-isoquinoline-methanol as a yellow solid which was used directly in the next step. (c) A solution of 190 mg (1.19 mmol) of 6-isoquinoline-methanol in 1 ml of glacial acetic acid was treated with 2 ml of 30% HBr in glacial acetic acid and the mixture was heated at 70°C for 45 minutes. The reaction mixture was cooled, treated with 20 ml of diethyl ether and stirred at 0°C for 30 min. The resulting solid was filtered off, washed with diethyl ether and dried in a high vacuum. There was obtained 6-bromomethyl-isoquinoline hydrobromide (73% of theory) as a light brown solid; MS: 221, 223 (M)+- Example 5 70 mg (0.141 mmol) of β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate were dissolved in 1.0 ml of tetrabutyl-ammonium fluoride solution (1M in tetrahydrofuran) and stirred at room temperature for one hour. Subsequently, the mixture was partitioned between methylene chloride and aqueous 5% sodium hydrogen carbonate solution, then the organic phase was dried over magnesium sulphate and finally the solvent was distilled off under reduced pressure. The crude product (72 mg) was purified by chromatography on silica gel with a 10:1:0.1 mixture of methylene chloride, methanol and ammonia as the eluent. There were obtained 41 mg (83% of theory) of (3RS,4RS)-4-(4-fluoro-phenyl)-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine as a colourless solid. MS: 352 (M+H)+. The p-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate used as the starting material was prepared as follows: (a) 17.87 g (82.64 mmol) of ethyl 4-hydroxy-naphthalene-2-carboxylate [J.Agric.Chem S°C .Japan 24, 313 (1950)] were suspended in 900 ml of methylene chloride, the suspension was cooled to 0-5°Cand subsequently treated with 17.9 ml (91.02 mmol) of 2-(trimethylsilyl)-ethoxymethyl chloride (SEM chloride) and 28.3 ml (165.31 mmol) of N-ethyldiisopropylamine. The yellow solution was warmed to room temperature and stirred for 2 hours. The solvent was distilled off under reduced pressure and the crude product (58 g), without further purification, was chromatographed on silica gel using a 3:2 mixture of methylene chloride and hexane as the eluent. There were obtained 15.81 g (99% of theory) of ethyl 4-(2-trimethyl-silylethoxy-methoxy)-naphthalene-2-carboxylate as a light yellow oil; MS: 322, 324 (M)+. (b) A solution of 28.31 g (81.70 mmol) of ethyl 4-(2-trimethyl-siiylethoxy-methoxy)-naphthalene-2-carboxylate in 480 ml of diethyl ether was added dropwise within 90 minutes at -5 to 0°C under argon to a suspension of 3.29 g (86.69 mmol) of lithium aluminium hydride in 230 ml of diethyl ether. The reaction mixture was warmed to room temperature and stirred for 2 hours. For the working-up, the mixture was cooled to 0°C, treated dropwise with 25 ml of ethyl acetate and with 50 ml of saturated potassium sodium tartrate solution. A light yellowish solution containing a white precipitate resulted. The solution was warmed to room temperature [and] decanted off from the precipitate. The residue was suspended three times with diethyl ether and the solvent was decanted off each time. The combined organic phases were washed with water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (26.4 g) was chromatographed on silica gel using a 3:7 mixture of ethyl acetate and hexane. There were obtained 23.72 g (95% of theory) of [4-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-yl]-methanol as a light yellow oil; MS: 304 (M)+. (c) 23.72 g (77.91 mmol) of [4-(2-trimethylsilyl-ethoxy- methoxy)-naphthalen-2-yl]-methanol were dissolved in 350 m of carbon tetrachloride and the solution was cooled to 0°C . Thereupon, 350 ml of acetonitrile and 26.54 g (1.012 mmol) of triphenylphosphine were added. The light yellow solution was stirred at 0°C for 30 minutes, warmed to room temperature and stirred for a further 2 hours. A further 10.14 g (38.7 mmol) of triphenylphosphine were added and the reaction mixture was stirred at room temperature for 90 minutes. Subsequently, the mixture was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product was chromatographed on silica gel using a 3:7 mixture of methylene chloride and hexane as the eluent. There were obtained 15.81 g (63% of theory) of 2-chloromethyl-4-(p-trimethylsilyl- ethoxymethoxy)-naphthalene as a light yellow oil; MS: 322, 324 (M)+. (d) A solution of 4.00 g (20.5 mmol) of (3RS,4RS)-4-(4- fluorophenyl)-piperidin-3-ol in 1 50 ml of ethanol was treated with 2.80 g (26.4 mmol) of sodium carbonate and refluxed. A solution of 2.50 ml (21.1 mmol) of benzyl bromide in 50 ml of ethanol was added dropwise within one hour and thereafter the mixture was held at reflux temperature for 2 hours. The pale brownish suspension was filtered and the filtrate was concentrated under reduced pressure. Subsequently, the residue was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and finally the solvent was distilled off under reduced pressure. The crude product was chromatographed on silica gel using a 2:3 mixture of ethyl acetate and hexane as the eluent. There were obtained 4.34 g (74% of theory) of (3RS,4RS)-l-benzyl-4-(4-fluoro- phenyl)-piperidin-3-ol as a colourless solid; MS: 285 (M)+. (e) In an analogous manner to that described in Example 1 (g), by alkylating (3RS,4RS)-l-benzyl-4-(4-fluoro-phenyl)-piperidin- 3-ol with 2-chloromethyl-4-(p-trimethylsilylethoxymethoxy)- naphthalene there was obtained (3RS,4RS)-1-benzyl-4-(4-fIuoro-phenyl)-3-[4-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine as a light yellow oil; MS: 572 (M+H)+. (f) In an analogous manner to that described in Example 1 (d) by cleavage of the benzyl group by means of β-trimethylsilylethyl chloroformate from (3RS,4RS)-1-benzyl-4-(4-fluoro-phenyl)-3-[4-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine there was obtained β-trimethylsilylethyl (3RS,4RS)-4- (4-fluorophenyl)-3-[4-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate as a light yellow oil; MS: 626 (M+H)+. (g) 4.65 g (7.43 mmol) of β-trimethylsilylethyl (3RS,4RS)-4- (4-fluorophenyl)-3-[4-(2-trimethylsilyl-ethoxymethoxy)- naphthalen-2-ylmethoxy]-piperidin-1-carboxylate were dissolved in 40 ml of methanol, treated with 40 ml of a 2N solution of hydrogen chloride in methanol and stirred at 50°C for 90 minutes. Subsequently, the mixture was partitioned between methylene chloride and aqueous 5% sodium hydrogen carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was distilled off under reduced pressure. The crude product (6.8 g) was purified by chromatography on silica gel with a 3:7 mixture of ethyl acetate and hexane. There were obtained 2.93 g (80% of theory) of p-trimethylsilylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless solid; MS: 496 (M+H)+. Example 6 The following compounds were obtained in an analogous manner to that described in Example 5: 1) - 4-(4-Fluoro-phenyl)-3-(l-hydroxy-naphthalen-2-yl- methoxy)-piperidine as a light brown solid, MS: 351 (M)+, from (3- trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(l -hydroxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate; 2) - 4-(4-fluoro-phenyl)-3-(5-hydroxy-naphthalen-2-yl- methoxy)-piperidine as a colourless solid, MS: 351 (M)+, from β- trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(5-hydroxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate; 3) - 4-(4-fluoro-phenyl)-3-(6-hydroxy-naphthalen-2-yl- methoxy)-piperidine as a colourless solid, MS: 351 (M)+, from β- trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(6-hydroxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate; 4) - 4-(4-fluoro-phenyl)-3-(7-hydroxy-naphthalen-2-yl- methoxy)-piperidine as a light brown solid, MS: 351 (M)+, from β- trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(7-hydroxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate; 5) - 4-(4-fluoro-phenyl)-3-(8-hydroxy-naphthalen-2-yl- methoxy)-piperidine as a light yellow resin, MS: 352 (M+H)+, from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(8- hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate. The trimethylsilylethyl carbamates used as the starting materials were obtained as follows in analogy to the procedure described in Example 5 (a)-(f): (a) From methyl 1-hydroxy-naphthalene-2-carboxylate [J. Chem. S°C . 309 (1948)] by introducing the protecting group there was obtained methyl 1-(2-trimethylsilylethoxymethoxy)-naphthalene-2-carboxylate as a light yellow oil, MS: 333 (M+H)+. (b) Reduction of methyl 1-(2-trimethylsilyl-ethoxymethoxy)-naphthalene-2-carboxylate gave [1-(2-trimethyl-silylethoxy-methoxy)-naphthalen-2-yl]-methanol as a light yellow oil, MS: 305 (M+H)+ (c) Chlorination of [1-(2-trimethylsilylethoxy-methoxy)- naphthalen-2-yl]-methanol yielded 2-chloro-methyl-1-(β- trimethylsilylethoxymethoxy)-naphthalene as a colourless oil, MS: 322, 324 (M)+. (d) Alkylation of (3RS,4RS)-1-benzyl-4-(4-fluoro-phenyl)- piperidin-3-ol with 2-chloromethyl-1-(β-trimethylsilylethoxy- methoxy)-naphthalene yielded (3RS,4RS)-1-benzyl-3-(4-fluoro-phenyi)-3-[1-(2-trimethylsilylethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine as a light yellow oil, MS: 572 (M+H)+. (e) Cleavage of the N-benzyl group from (3RS,4RS)-1-benzyl-3-(4-fluorophenyl)-3-[1-(2-trimethylsilylethoxy-methoxy)-naphth-alen-2-ylmethoxy]-piperldine with β-trimethylsilylethyl chloro-formate gave β-trimethylsilylethyl (3RS, 4RS)-4-(4-fluoro-phenyl)-3-[1-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate as a colourless oil, MS: 626 (M+H)+. (f) Cleavage of the SEM group from β-trimethylsilylethyl (3RS, 4RS)-4-(4-fluorophenyl)-3-[1-(2-trimethylsilyl-ethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate yielded β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3- (1 -hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate as a colourless oil, MS: 494 (M-H)". (g) From 5-hydroxy-naphthalene-2-carboxylic acid [Bull. S°C . Chim. Fr., 857 (1953)] there was obtained firstly by esterification with methanol/sulphuric acid methyl 5-hydroxy- naphthalene-2-carboxylate as a light yellow solid, MS: 202 (M)+. By introducing the protecting group there was obtained methyl 5- (2-trimethylsilyl-ethoxymethoxy)-naphthalene-2-carboxylate as a light yellow oil, MS: 333 (M+H)+. (h) Reduction of methyl 5-(2-trimethylsilyl-ethoxymethoxy)-naphthalene-2-carboxylate gave [5-(2-trimethylsilyl-ethoxy- methoxy)-naphthalen-2-yl]-methanol as a light yellow oil, MS: 305 (M+H)+. (i) Chlorination of [5-(2-trimethylsilyl-athoxymethoxy)-naphthalen-2-yl]-methanol yielded 2-chloro-methyl-5-(β- trimethyl-silylethoxy-methoxy)-naphthalene as a colourless oil, MS: 322, 324 (M)+. G) Alkylation of (3RS,4RS)-l-benzyl-4-(4-fluoro-phenyl)-piperidin-3-ol with 2-chloromethyl-5-(β-trimethyl-silylethoxy-methoxy)-naphthalene yielded (3RS,4RS)-1-benzyl-3-(4-fluoro-phenyl)-3-[5-(2-tri-methylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine as a light yellow oil, MS: 572 (M+H)+. (k) Cleavage of the N-benzyl group from (3RS,4RS)-l-benzyl-3-(4-fluoro-phenyl)-3-[5-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine with β-trimethylsilylethyl chloroformate gave β-trimethylsilylethyl (3RS,4RS)-4-(4-fluoro-phenyl)-3-[5-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-l-carboxylate as a colourless oil, MS: 626 (M+H)+. (I) Cleavage of the SEM group in β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[5-(2-trimethylsilyl-ethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidlne-l-carboxylate yielded β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3- (5-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil, MS: 494 (M-H)~. (m) From ethyl 6-hydroxy-naphthalene-2-carboxylate [J. Chem. S°C . 1 23. 1654 (1923)] by introducing the protecting group there was obtained ethyl 6-(2-trimethylsilyl-ethoxymethoxy)-naphthalene-2-carboxylate as a light yellow oil, MS: 346 (M)+. (n) Reduction of ethyl 6-(2-trimethylsilyl-ethoxymethoxy)-naphthalene-2-carboxylate gave [6-(2-trimethylsilyl-ethoxy-methoxy)-naphthalen-2-yl]-methanol as a colourless solid, MS: 304 (M)+. (o) Chlorination of [6-(2-trimethylsilyl-ethoxy-methoxy)-naphthalen-2-yl]-methanol yielded 6-chloromethyl-1-(β-tri- methylsilylethoxymethoxy)-naphthalene as a colourless oil, MS: 322, 324 (M)+ (p) Alkylation of (3RS,4RS)-1-benzyl-4-(4-fluoro-phenyl)-piperidin-3-ol with 6-chloromethyl-l-(β-trimethylsilyl- ethoxymethoxy)-naphthalene yielded (3RS,4RS)-1-benzyl-3-(4-fluorophenyl)-3-[6-(2-trimethyl-silylethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine as a light yellow oil, MS: 572 (M+H)+. (q) Cleavage of the N-benzyl group from (3RS,4RS)-l-benzyl-3-(4-fluorophenyl)-3-[6-(2-trimethyl-silylethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine with β-trimethylsilylethyl chloroformate gave β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[6-(2-trimethylsilylethoxy-methoxy)-naphthalen-2-yl-methoxy]-piperidine-l-carboxylate as a colourless oil, MS: 626 (M+H)+. (r) Cleavage of the SEM group from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[6-(2-trimethylsilylethoxy- methoxy)-naphthalen-2-yl-methoxy]-piperidine-l-carboxylate yielded β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3- (6-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless resin, MS: 495 (M)+. (s) From 7-hydroxy-naphthalene-2-carboxylic acid [Bull. S°C . Chim. Fr., 573 (1952)] there was firstly obtained by ester-ification with methanol/sulphuric acid methyl 7-hydroxy-naphthalene-2-carboxylate as a colourless solid, MS: 202 (M)+. Introduction of the protecting group yielded methyl 7-(2-tri-methylsilyl-ethoxymethoxy)-naphthalene-2-carboxylate as a light yellow oil, MS: 332 (M)+. (t) Reduction of methyl 7-(2-trimethylsilyl-ethoxymethoxy)-naphthalene-2-carboxylate gave [7-(2-trimethylsilyl-ethoxy- methoxy)-naphthalen-2-yl]-methanol as a light yellow oil, MS: 304 (M)+. (u) Chlorination of [7-(2-trimethylsilyl-ethoxy-methoxy)-naphthalen-2-yi]-methanol yielded 2-chloromethyl-7-(β- trimethyl-silylethoxymethoxy)-naphthalene as a light yellow oil, MS: 322, 324 (M)+. (v) Alkylation of (3RS,4RS)-1-benzyl-4-(4-fluoro-phenyl)-piperidin-3-ol with 2-chloromethyl-7-(β-trimethyl-silylethoxy- methoxy)-naphthalene yielded (3RS,4RS)-l-benzyl-3-(4-fluoro-phenyl)-3-[7-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine as a light yellow oil, MS: 572 (M+H)+. (w) Cleavage of the N-benzyl group from (3RS,4RS)-1-benzyl-3-(4-fluoro-phenyl)-3-[7-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine with β-trimethylsilylethyl chloroformate yielded β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[7-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-l-carboxylate as a colourless oil, MS: 626 (M+H)+. (x) Cleavage of the SEM group from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[7-(2-trimethylsilyl-ethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate yielded β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3- (7-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow oil, MS: 495 (M)+. (y) From 8-hydroxy-naphthalene-2-carboxylic acid [Bull. S°C . Chim. Fr., 857 (1953)] there was firstly obtained by esterific-ation with methanol/sulphuric acid methyl 8-hydroxy-naphthalene-2-carboxylate as a light yellow solid, MS: 202 (M)+. Introduction of the protecting group yielded methyl 8-(2-trimethylsilyl-ethoxymethoxy)-naphthalene-2-carboxylate as a colourless solid, MS: 274 [M-(C2H4+CH2O )]+. (z) Reduction of methyl 8-(2-trimethylsilyl-ethoxymethoxy)-naphthalene-2-carboxylate gave [8-(2-trimethylsilyl-ethoxy-methoxy)-naphthalen-2-yl]-methanol as a colourless oil, MS: 304 (M)+ (aa) Chlorination of [8-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-yl]-methanol yielded 2-chloromethyl-8-(2-trimethylsilylethoxy-methoxy)-naphthalene as a light yellow oil, MS: 322, 324 (M)+. (bb) Alkylation of (3RS,4RS)-l-benzyl-4-(4-fluoro-phenyl)-piperldin-3-ol with 2-chloromethyl-8-(2-trimethylsilylethoxy-methoxy)-naphthalene yielded (3RS,4RS)-1-benzyl-3-(4-fluoro-phenyl)-3-[8-(2-trimethylsilylethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine as a light yellow oil, MS: 572 (M+H)+. (cc) Cleavage of the N-benzyl group from (3RS,4RS)-1-benzyl-3-(4-fluoro-phenyl)-3-[8-(2-trimethylsilylethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine with (3-trimethylsilylethyl chloroformate gave β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[8-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate as a colourless oil, MS: 626 (M+H)+. (dd) Cleavage of the SEM group from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[8-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-yl-methoxy]-piperidine-l-carboxylate yielded β-trimethylsilylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-(8-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil, MS: 494 (M-H)". Example 7 The following compounds were prepared in an analogous manner to that described in Examples 3 and 5: 1) (3RS,4RS)-4-(4-Fluorophenyl)-3-(3-hydroxy-naphthalen-2-ylmethoxy)-piperidine In an analogous manner to that described in Examples 3 and 5 (g), by cleaving off the two protecting groups with methanolic hydroc hloric acid from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-[3-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate there was obtained (3RS,4RS)-4-(4-fluorophenyl)-3-(3-hydroxy-naphthalen-2-yl-methoxy)-piperidine as a colourless solid, MS: 351 (M)+. The tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-[3-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate used as the starting material was prepared as follows: (a) In an analogous manner to that described in Example 5 (a), from methyl 3-hydroxy-naphthalene-2-carboxylate by introducing the protecting group there was obtained methyl 3-(2-trimethyl-silyl-ethoxy-methoxy)-naphthalene-2-carboxylate as a light yellow oil, MS: 274 (M-(C2H4+CH2O)]+. (b) In an analogous manner to that described in Example 5(b), reduction of methyl 3-(2-trimethylsilyl-ethoxy-methoxy)-naphthalene-2-carboxylate gave [3-(2-trimethylsilylethoxy-methoxy)-naphthalen-2-yl]-methanol as a light yellow oil, MS: 304 (M)+ (c) 400 mg (1.30 mmol) of [3-(2-trimethylsilylethoxy-methoxy)-naphthalen-2-yl]-methanol and 462 mg (1.81 mmol) of carbon tetrabromide were dissolved in 5 ml of absolute acetonitrile and the solution was cooled to 0°C . A solution of 446 mg (1.68 mmol) of triphenylphosphine in 6 ml of absolute acetonitrile was added dropwise thereto at 0°C within 10 minutes and thereafter the mixture was stirred at 0°C for a further 30 minutes. Subsequently, the solvent was distilled off under reduced pressure and, for purification, the crude product was chromatographed, without further working up, on silica gel using a 2:3 mixture of methylene chloride and hexane as the eluent. There were obtained 314 mg (65% of theory) of 2-bromo- methyl-3-(2-trimethylsilylethoxymethoxy)-naphthalene as a light yellow oil; MS: 366, 368 (M)+. (d) In an analogous manner to that described in Example 3 (c), by alkylating tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3- hydroxy-piperidine-1-carboxylate with 2-bromomethyl-3-(2- trimethylsilylethoxy-methoxy)-naphthalene there was obtained tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-[3-(2-trimethylsilyl- ethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine-1- carboxylate as a light yellow oil; MS: 523 [M-(C2H4 + CH2O)]+. 2) (3RS,4RS)-4-(4-Fluorophenyl)-3-(l -methoxy-naphthalen-2-yl-methoxy)-piperidine In an analogous manner to that described in Example 3, by cleavage of the B°C protecting group from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-[1-methoxy-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate there was obtained (3RS,4RS)-4-(4-fluorophenyl)-3-(l-methoxy-naphthalen-2-yl-methoxy)-piperidine as a light yellow oil; MS: 365 (M)+. The tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-[1-methoxy-naphthalen-2-ylmethoxy]-piperidine-l -carboxylate used as the starting material was obtained as follows: (e) In an analogous manner to that described in Example 5 (b), by reducing methyl 1-methoxy-naphthalene-2-carboxylate [J. Chem. S°C . 121.1657 (1922)] there was obtained [1-methoxy)-naphthalen-2-yl]-methanol as a colourless solid; MS: 188 (M)+. (f) In an analogous manner to that described in Example 7 (c), by brominating [1-methoxy)-naphthalen-2-yl]-methanol there was obtained 2-bromomethyl-1-methoxy-naphthalene as a colourless solid; MS: 250, 252 (M)+. (g) In an analogous manner to that described in Example 3 (c), by alkylating tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-1-carboxylate [Example 3 (b)] with 2-bromo- methyl-1-methoxy-naphthalene there was obtained tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-[1-methoxy-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate as a colourless resin; MS: 465 (M)+ 3) (3RS,4RS)-4-(4-Fluorophenyl)-3-(3-methoxy-naphthalen-2-yl-methoxy)-piperidine In an analogous manner to that described in Example 3, by cleavage of the B°C protecting group from tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-[3-methoxy-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate there was obtained (3RS,4RS)-4-(4-fluorophenyl)-3-(3-methoxy-naphthalen-2-yl-methoxy)-piperidine as a light yellow oil; MS: 365 (M)+. The tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-[3-methoxy-naphthalen-2-ylmethoxy]-piperidine-l -carboxylate used as the starting material was obtained as follows: (h) In an analogous manner to that described in Example 5 (b), by reducing methyl 3-methoxy-naphthalene-2-carboxylate [J. Chem. S°C . 2351 (1950)] there was obtained [3-methoxy)-naphthalen-2-yl]-methanol as a colourless solid; MS: 188 (M)+. (i) In an analogous manner to that described in Example 7 (c), by brominating [3-methoxy)-naphthalen-2-yl]-methanol there was obtained 2-bromomethyl-3-methoxy-naphthalene as a colourless solid; MS: 250, 252 (M)+. (j) In an analogous manner to that described in Example 3 (c), by alkylating tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-1-carboxylate [Example 3 (b)] with 2-bromo-methyl-3-methoxy-naphthalene there was obtained tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-[3-methoxy-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate as a colourless resin; MS: 465 (M)+. Example 8 (a) To 1.46 g of magnesium shavings, which had previously been covered with tetrahydrofuran, was added dropwise a solution of 12.06 g (60 mmol) of 5-bromo-benzo[1,3]dioxol in 30 ml of absolute tetrahydrofuran, followed by 11.35 g (60 mmol) of l-benzyl-4-piperidone. The reaction mixture was stirred at 50°C for 1 hour, then poured on to ice and ammonium chloride solution. The 4-benzo[1,3]dioxol-5-yl-l-benzyl-piperidin-4-ol formed was extracted with ethyl acetate and crystallized upon concentration of the solution. There were obtained 10,85 g (58% of theory) of white crystals; m.p.: 144°C . (b) In an analogous manner to that described in Example 2(e), from 4-benzo[l,3]dioxol-5-yl-1-benzyl-piperidin-4-ol by catalytic hydrogenation at normal pressure within 4 hours there was obtained 4-benzo[1,3]dioxol-5-yl-piperidin-4-ol as a colourless solid in quantitative yield; MS: 221 (M)+. (c) In an analogous manner to that described in Example 1 (b), from 4-benzo[l,3]dioxol-5-yl-piperidin-4-ol by elimination there was obtained 4-benzo[1,3]dioxol-5-yl-l,2,3,6-tetrahydro-pyridine as a beige coloured solid; MS: 203 (M)+, (d) In an analogous manner to that described in Example 1 (f), from 4-benzo[l,3]dioxol-5-yl-l,2,3,6-tetrahydro-pyridine by introducing the B°C group there was obtained tert-butyl 4-benzo[1,3]dioxol-5-yl-3,6-dihydro-2H-pyridine-l -carboxylate as a colourless oil; MS: 304 (M+H)+. (e) In an analogous manner to that described in Example 1 (c), by hydroborating tert-butyl 4-benzo[l ,3]dioxol-5-yl-3,6-dihydro-2H-pyridine-1-carboxylate there was obtained tert-butyl (3RS,4RS)-4-benzo[l ,3]dioxol-5-yl-3-hydroxy-piperidine-l -carboxylate as white crystals; m.p.: 112°C . (f) In an analogous manner to that described in Example 1 (g), by alkylating tert-butyl (3RS,4RS)-4-benzo[l,3]dioxol-5-yl-3- hydroxy-piperidine-1-carboxylate with 2-bromomethyl-naphthalene there was obtained tert-butyl (3RS,4RS)-4-benzo-[1,3]dioxol-5-yl-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate as white crystals after crystallization from hexane; m.p.: 1 28-129°C . (g) A solution of 190 mg (0.41 mmol) of tert-butyl (3RS,4RS)-4-benzo[l ,3]dioxol-5-yl-3-(naphthalen-2-ylmethoxy)-piperidine 1-carboxylate in a mixture of 5 ml of methanol and 25% aqueous hydroc hloric acid was heated under reflux for 1 hour. Subse¬quently, the solvent mixture was distilled off under reduced pressure. After recrystallization of the residue from a mixture of methanol and ether there were obtained 130 mg (73% of theory) of (3RS,4RS)-4-(l ,3-benzodioxol-5-yl)-3-naphthalen-2-ylmethoxy-piperidine hydroc hloride as a white powder; MS: 362 (M+H)+. Example 9 The following compounds were obtained in an analogous manner to that described in Example 8(g) by cleavage of the B°C group using acid: 1) - Pyridine-3-carboxylic acid (3RS,4RS)-2-(4-phenyl-piperidin-3-yioxymethyl)-benzylamide hydroc hloride as a beige coloured powder, MS: 402 (M+H)+, from tert-butyl (3RS,4RS)-4-phenyl-3-(2-{[(pyridine-3-carbonyl)-amino]-methyl}-benzyloxy)-piperidine-1 -carboxylate; 2) - (3RS,4RS)-2-(4-[l ,3]benzodioxol-5-yl-piperidin-3-yloxymethyl)-benzamide hydroc hloride as a white powder, MS: 355 (M+H)+, from tert-butyl (3RS,4RS)-4-benzo[l,3]dioxol-5-yl-3-(2-carbamoyl-benzyloxy)-piperidine-l-carboxylate. The B°C derivatives used as the starting materials were prepared as follows: (a) In an analogous manner to that described in Example 1 (g), by alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-phenyl-piperidine- 1-carboxylate [Example 2(a)] with 2-bromomethylbenzonitrile there was obtained tert-butyl (3RS,4RS)-3-(2-cyano-benzyloxy)-4-phenyl-piperidine-1-carboxylate as a colourless oil; MS: 393 (M+H)+ (b) 528 mg (1.35 mmol) of tert-butyl (3RS,4RS)-3-(2-cyano-benzyloxy)-4-phenyl-piperidine-l-carboxylate were reduced with 0.3 ml of borane-dimethyl sulphide complex in analogy to the process described by H.C.Brown et al. in Synthesis 1981, 605. There were obtained 480 mg (90% of theory) of tert-butyl (3RS,4RS)-3-(2-aminomethyl-benzyloxy)-4-phenyl-piperidine-1-carboxylate as a colourless solid; 397 (M+H)+. (c) A solution of 150 mg (0.38 mmol) of tert-butyl (3RS,4RS)-3-(2-aminomethyl-benzyloxy)-4-phenyl-piperidine-1-carboxylate in 2 ml of methylene chloride was treated with 229 mg (2.26 mmol) of triethylamine, 139 mg (1.05 mmol) of nicotinic acid, 216 mg (1.13 mmol) of EDC and 10 mg (0.08 mmol) of 4-dimethylaminopyridine and the mixture was stirred at room temperature for 24 hours. Thereafter, the reaction solution was diluted with methylene chloride and washed with a saturated sodium hydrogen carbonate solution. The organic phase was separated, dried over sodium sulphate and evaporated under reduced pressure. The residue was chromato-graphed on silica gel using ethyl acetate as the eluent. There were obtained 100 mg (53% of theory) of tert-butyl (3RS,4RS)-4-phenyl-3-(2-{[(pyridine-3-carbonyl)-amino]-methyl}-benzyl-oxy)-piperidine-1-carboxylate as a colourless solid; MS: 502 (M+H)+. (d) In an analogous manner to that described in Example 1 (g), by alkylating tert-butyl (3RS,4RS)-4-benzo[1,3]dioxol-5-yl-3- (naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate [Example 8(f)] with 2-bromomethyl-benzonitrile there was obtained tert- butyl (3RS,4RS)-4-benzo[1,3]dioxol-5-yl-3-(2-cyano-benzyloxy)- piperidine-1-carboxylate as colourless crystals; MS: 455 (M+H)+. (e) 0.5 ml of hydrogen peroxide (33%) and 0.2 ml of 2N sodium hydroxide solution were added to a solution of 236 mg (0.54 mmol) of tert-butyl (3RS,4RS)-4-benzo[l,3]dioxol-5-yl-3-(2-cyano-benzyloxy)-piperidine-l-carboxylate in 5 ml of methanol. The reaction solution was heated under reflux for 2 hours. Subsequently, the same amounts of hydrogen peroxide and sodium hydroxide solution were again added and the solution was heated for a further 2 hours. Thereafter, the solution was cooled and evaporated under reduced pressure. For purification, the residue was chromatographed on silica gel using a 9:1 mixture of methylene chloride and ether as the eluent. There were obtained 140 mg (57% of theory) of tert-butyl (3RS,4RS)-4-benzo[l ,3]dioxol-5-yl-3-(2-carbamoyl-benzyloxy)-piperidine-l -carboxylate as a colourless solid; MS: 455 (M+H)+. Example 10 (a) In an analogous manner to that described in Example 1 (g), by alkylating tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-1-carboxylate with 6-chloromethyl-2,3-dihydro-benzo[l,4]dioxin [Brit. Pat. 566732 (1943)] there was obtained tert-butyl (3RS,4RS)-3-(2,3-dihydro-benzo[l ,4]dioxin-6-ylmethoxy)-4-(4-fluorophenyl)-piperidine-l-carboxylate as a colourless solid; MS: 444 (M+H)+; (b) A solution of 280 mg (0.63 mmol) of tert-butyl (3RS,4RS)-3-(2,3-dihydro-benzo[l,4]dioxin-6-ylmethoxy)-4-(4-fluoro-phenyl)-piperidine-l-carboxylate in 5 ml of dry methylene chloride was treated with 808 mg (1.89 mmol) of anhydrous zinc bromide and the mixture was stirred at room temperature for 5 hours. Subsequently, the solvent was distilled off under reduced pressure, the residue was taken up in 10 ml of methanol, treated with 2 ml of 2N sodium hydroxide solution and the solid was separated. The filtrate was evaporated under reduced pressure and the residue was partitioned between methylene chloride and water. The organic phase was separated and evaporated under reduced pressure. There were obtained 220 mg (98% of theory) of (3RS,4RS)-3-(2,3-dihydrobenzol[1,4]dioxin-6- yl-methoxy)-4-(4-fluorophenyl)-piperidine as a yellowish solid; MS: 344 (M+H)+. Example 11 In an analogous manner to that described in Example 10(b), from tert-butyl (3RS,4RS)-3-(benzo[b]furan-5-ylmethoxy)-4-(4-fluoro-phenyl)-piperidine-l-carboxylate there was obtained (3RS,4RS)-3-(benzo[b]furan-5-ylmethoxy)-4-(4-fluorophenyl)-piperidine as a colourless solid; MS: 326 (M+l)+; The tert-butyl (3RS,4RS)-3-(benzo[b]furan-5-ylmethoxy)-4-(4-fluoro-phenyl)-piperidine-1-carboxylate used as the starting material was obtained as a colourless solid, MS: 426 (M+H)+, analogously to the procedure described in Example 1 (g) by alkylating tert-butyl (3RS,4RS)-4-(4-fluorophenyl)-3-hydroxy-piperidine-1 -carboxylate. The 5-bromomethyl-benzo[b]furan used as the alkylating agent was prepared as follows: By brominating 5-methyl-benzo[b]furan[Synth. Commun. 19, 257(1989)] with N-bromosuccinimide in carbon tetrachloride in an analogous manner to the procedure for the preparation of 5-bromomethyl-benzo[b]thiophene [J. Med. Chem. 34(1), 65(1991)] from 5-methyl-benzo[b]thiophene there was obtained 5-bromo-methyl-benzo[b]furan as a light yellow solid; MS: 210, 212 (M)+. Example 12 (a) In an analogous manner to that described in Example 1 (c), from 4-(4-chloro-phenyl)-1 -methyl-1,2,3,6-tetrahydropyridine [US Pat. 3 320 265] by hydroboration using borane in tetra-hydrofuran there was obtained (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin-3-ol which, after recrystallizatlon from a mixture of methylene chloride and hexane, formed colourless crystals of m.p.: 99-100°C . (b) A solution of 1.12 g (5 mmol) of (3RS,4RS)-4-(4-chloro- phenyl)-1-methyl-piperidine-3-ol in 5 ml of tetrahydrofuran was added dropwise to a suspension of 0.264 g (5 mmol) of sodium hydride (50% dispersion in refined oil) in 8 ml of tetrahydrofuran and the mixture was stirred at 50°C for 60 minutes. Subse¬ quently, it was cooled to room temperature and treated with 1.10 g (5 mmol) of 2-bromomethyl-naphthalene in 5 ml of tetrahydrofuran. After 2 hours at 50°C the reaction solution was poured into 60 ml of ice-water and extracted three times with 25 ml of ethyl acetate each time. The organic phases were washed with saturated sodium chloride solution, dried over magnesium sulphate, filtered and evaporated. The residue was chromatographed on silica gel using a 95:5 mixture of methylene chloride and ethanol as the eluent. There was obtained 0.53 g (28% of theory) of (3RS,4RS)-4-(4-chloro-phenyl)-l-methyl-3- (naphthalen-2-ylmethoxy)-piperidine as a pale yellow oil; MS: 366 (M)+. (c) A solution of 0.526 g (1.43 mmol) of (3RS,4RS)-4-(4- chloro-phenyl)-1-methyl-3-(naphthalen-2-ylmethoxy)-piperidine in 12 ml of toluene was treated with 100 mg of potassium carbonate and heated to 100°. Subsequently, 0.423 g (0.288 ml, 2 mmol) of 2,2,2-trichloroethyl chloroformate was added thereto and the mixture was stirred at 100° for 12 hours. The reaction solution was evaporated, taken up in 50 ml of ethyl acetate and washed with 20 ml of water and 20 ml of saturated sodium hydrogen carbonate solution. Drying over magnesium sulphate, filtration (sic) and evaporation yielded a colourless oil which was chromatographed on silica gel using a 3:2 mixture of hexane and ethyl acetate as the eluent. There was obtained 0.426 g (57% of theory) of 2,2,2-trichloroethyl 4-(4-chloro-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil; Rf: 0.31 (silica gel, hexane/ethyl acetate: 3/2). (d) A suspension of 0.420 g (0.8 mmol) of 2,2,2-trichloroethyl 4-(4-chloro-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1- carboxylate and 300 mg of zinc in 10 ml of acetic acid was stirred at room temperature for 12 hours. I ne reaction solution was diluted with 40 ml of water and extracted four times with 30 ml of methylene chloride. The organic phase was washed twice with 40 ml of IN sodium hydroxide solution each time, dried over sodium sulphate, filtered and evaporated. The residue was chromatographed on silica gel using a 9:1 mixture of methyl¬ene chloride and methanol as the eluent. There was obtained 0.210 g (74% of theory) of (3RS,4RS)-4-(4-chloro-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine, MS: 210 (M - C11H9)+, which was converted into the hydroc hloride of m.p. 159-1 61 °C (dec.) with a solution of hydrogen chloride in methanol. Example 13 The following compounds were prepared in an analogous manner to that described in Example 12(b)-(d) by alkylation and subsequent cleavage of the N-methyl group: 1) - from (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin-3-ol and 1-bromomethylnaphthalene, (3RS,4RS)-4-(4-chloro-phenyl)-3-(naphthalene-l-ylmethoxy)-piperidine, MS: 210 (M-C11H9)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 210-213°C (dec). 2) - from (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin-3-ol and l-bromomethyl-4-tert-butylbenzene, (3RS,4RS)-3-(4-tert.butyi-benzyioxy)-4-(4-chloro-phenyl)-piperidine, MS: 358 (M)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 164-166°C (dec). 3) - from (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin-3-ol and 5-chloromethyl-benzo[1.3]dioxol, (3RS,4RS)-3-(benzo-[1.3]dioxol-5-yl-methoxy)-4-(4-chloro-phenyl)-piperidine, MS: 210 ( M-C8H7O2)+ which was converted with methane-sulphonic acid in a mixture of dioxan and water and subsequent lyophilization into the corresponding methanesulphonate; Rf: 0.45 (silica gel, methylene chloride/methanol: 9/1). 4) - from (3RS,4RS)-4-(4-chloro-phenyl)-l-methyl-piperidin-3-ol and l,2-dichloro-4-chloromethylbenzene, (3RS,4RS)-4-(4-chloro-phenyl)-3-(3,4-dichlorobenzyloxy)-piperidine, MS: 370 (M)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 1 56-158°C (dec). 5) - from (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin-3-ol and 2,4-dichloro-1-chloromethyIbenzene, (3RS,4RS)-4-(4-chloro-phenyl)-3-(2,4-dichloro-benzyloxy)-piperidine of m.p. 83-840C; MS: 370 (M)+. 6) - from (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin-3-ol and 1-chloro-4-chloromethylbenzene, (3RS,4RS)-3-(4-chlorobenzyloxy)-4-(4-chloro-phenyl)-piperidine, MS: 210 (M-C7H6Cl)+ which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 128-130°C (dec). 7) - from (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin-3-ol and 1-chloromethyl-3-methoxy-benzene, (3RS,4RS)-(4-chloro-phenyl)-3-(2-methoxy-benzyloxy)-piperidine, MS: 332 (M)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 116-118°C (dec). 8) - from (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin-3-ol and 1-chlor0-2-chloromethyl-benzene, (3RS,4RS)-3-(2- chlorobenzyloxy)-4-(4-chloro-phenyl)-piperidine, MS: 210 (M-C7H6CI)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 145-147°C (dec). 9) - from (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin- 3-ol and 4-chloromethyl-biphenyl, (3RS,4RS)-3-(biphenyl-4- ylmethoxy)-4-(4-chloro-phenyl)-piperidine, MS: 210 (M-C13H11)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 177-180°C (dec). 10) - from (3RS,4RS)-4-(4-chloro-phenyl)-l-methyl-piperidin-3-ol and 2-chloromethyl-quinoline, (3RS,4RS)-2-[4-(4-chloro-phenyl)-piperidin-3-yloxy-methyl]quinoline, MS: 353 (M)+ of m.p. 109-1I0°C . 11) - from (3RS,4RS)-4-(4-chloro-phenyl)-l-methyl-piperidin-3-ol and 3-chloromethyl-benzofuran [J.Am. Chem. S°C . 73, 4400 (1951)], (3RS,4RS)-3-(benzofuran-2-ylmethoxy)-4-(4-chloro-phenyl)-piperidine, MS: 341 (M)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 144-146°C (dec). 12) - from (3RS,4RS)-4-(4-chloro-phenyl)-l-methyl-piperidin-3-ol and 2-chloromethyl-benzo[b]thiophene [J. Am.Chem. S°C . 71, 2856 (1949)], (3RS,4RS)-3-(benzo[b]thiophen-2-ylmethoxy)-4-(4-chloro-phenyl)-piperidine, MS: 210 (M-C8H7S)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 141-144°C (dec). 13) - from (3RS,4RS)-4-(4-chloro-phenyl)-1-methyl-piperidin-3-ol and methyl 4'-bromomethyl-biphenyl-2-carboxylate [J. Med. Chem. 34, 2525 (1991)], methyl (3RS,4RS)-4'-[4-(4-chloro-phenyl)piperidln-3-yloxy-methyl]-biphenyl-2-carboxylate, MS: 436 (M)+' which was converted with hydroc hloric acid in ethanol into the hydroc hloride of m.p. 95-99°C (dec). 14) - from (3RS,4RS)-4-(4-chloro-phenyi)-l-methyl-piperidin-3-ol and 3-chloromethyl-pyridine [J. Am. Chem. S°C . 77, 1054 (1955)], (3RS,4RS)-3-[4-(4-chloro-phenyl-piperidin-3-yIoxy-methyl]-pyridine, MS: 303 (M)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 78-8I°C (dec). 15) - from (3RS,4RS)-4-(4-chloro-phenyl)-l-methyl-piperidin-3-ol and 6-chloromethyl-1,1,4,4,-tetramethyl-l,2,3,4-tetra-hydronaphthalene, (3RS,4RS)-4-(4-chloro-phenyl)-3-(5,5,8,8,-tetramethyl-5,6,7,8-tetrahydronaphthalene-2-ylmethoxy)-piperidine, MS: 412 (M)+, which was converted with a solution of hydrogen chloride in ethanol into the hydroc hloride of m.p. 118-121°C (dec). 16) - from (3RS,4RS)-4-(3-chloro-phenyl)-1-methyl-piperidin-3-ol [US Pat. 4 132 710 (1976)] and 4-methoxybenzyl chloride, (3RS,4RS)-3-(4-methoxy-benzyloxy)-4-(3-chloro-phenyl)-piperidine; MS: 332 (M)+. Example 14 The following compounds were prepared in analogy to the procedure described in Example 1 (e) by cleavage of the 2-trimethylsilyl-ethoxycarbonyl group with tetrabutylammonium fluoride in tetrahydrofuran: 1) - (3RS,4RS)-4-(4-fluorophenyl)-3-(4-methoxy-naphthalen- 2-ylmethoxy)-piperidine as a colourless solid, MS: 365 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4- methoxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 2) - (3RS,4RS)-4-(4-fluorophenyl)-3-(5-methoxy-naphthalen- 2-ylmethoxy)-piperidine as a colourless solid, MS: 365 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(5- methoxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 3) - (3RS,4RS)-4-(4-fluorophenyl)-3-(6-methoxy-naphthalen- 2-ylmethoxy)-piperidine as a colourless solid, MS: 365 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyi)-3-(6- methoxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 4) - (3RS,4RS)-4-(4-fluorophenyl)-3-(7-methoxy-naphthalen- 2-ylmethoxy)-piperidine as a colourless solid, MS: 365 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(7- methoxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 5) - (3RS,4RS)-4-(4-fluorophenyi)-3-(8-methoxy-naphthalen- 2-ylmethoxy)-piperidine as a colourless resin, MS: 366 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(8-methoxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 6) - (3RS,4RS)-4-(4-fluorophenyl)-3-[4-(pyridin-2-yi-methoxy)-naphthalen-2-ylmethoxy]-piperidine as a colourless solid, MS: 442 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[4-(pyridin-2-ylmethoxy)-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate; 7) - (3RS,4RS)-4-(4-fluorophenyl)-3-[4-(pyridin-3-yl-methoxy)-naphthalen-2-ylmethoxy]-piperidine as a colourless solid, MS: 443 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[4-(pyridin-3-ylmethoxy)-naphthalen-2-yl-methoxy]-piperidine-l-carboxylate; 8) - (3RS,4RS)-4-(4-fluorophenyl)-3-[4-(pyridin-4-yl- methoxy)-naphthalen-2-ylmethoxy]-piperidine as a colourless solid, MS: 442 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-[4-(pyridin-4-ylmethoxy)-naphthalen-2-yl-methoxy]-piperidine-l-carboxylate; 9) - (3RS,4RS)-3-(4-allyloxy-naphthalen-2-ylmethoxy)-4-(4- fluorophenyl)-piperidine as a colourless solid, MS: 391 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-3-(4-allyloxy-naphthalen-2- ylmethoxy)-4-(4-fluorophenyl)-piperidine-1-carboxylate; 10) - (3RS,4RS)-3-(6-allyloxy-naphthalen-2-ylmethoxy)-4-(4- fluorophenyl)-piperidine as a colourless solid, MS: 391 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-3-(6-allyloxy-naphthalen-2- ylmethoxy)-4-(4-fluorophenyl)-piperidine-1-carboxylate; 11) - (3RS,4RS)-4-(4-fluorophenyl)-3-(4-isobutyloxy- naphthalen-2-ylmethoxy)-piperidine as a colourless solid, MS: 407 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-(4-isobutoxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate; 12) - (3RS,4RS)-3-(1-benzyloxy-naphthalen-2-ylmethoxy)-4- (4-fluorophenyl)-piperidine as a light yellow oil, MS: 441 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-3-(l-benzyloxy- naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-1- carboxylate; 13) - (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine as a colourless solid, MS: 441 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-1-carboxylate; 14) - (3RS,4RS)-3-(5-benzyloxy-naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine as a light yellow oil, MS: 442 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-3-(5-benzyloxy- naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-1-carboxylate; 15) -(3RS,4RS)-3-(7-benzyloxy-naphthalen-2-ylmethoxy)-4- (4-fluorophenyl)-piperidine as a colourless solid, MS: 441 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-3-(7-benzyloxy- naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-1-carboxylate; 16) - (3RS,4RS)-3-(8-benzyloxy-naphthalen-2-ylmethoxy)-4- (4-fluorophenyl)-piperidine as a light yellow resin, MS: 442 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-3-(8-benzyloxy- naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-1-carboxylate; 17) - (3RS,4RS)-4-(4-fIuorophenyl)-3-[4-(2-methoxy-ethoxy)- naphthalen-2-ylmethoxy]-piperidine as a colourless solid, MS: 410 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-[4-(2-methoxy-ethoxy)-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate; 18) - 4-(4-fluorophenyl)-3-[4-(3-methoxy-propoxy)- naphthalen-2-ylmethoxy]-piperidine as a light yellow solid, MS: 424 (M+H)+, from β-trimethyl-silylethyl 4-(4-fluorophenyl)-3-[4-(3-methoxy-propoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate; 19) - (3RS,4RS) 3-(4-butoxy-naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine as a colourless solid, MS: 408 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS) 3-(4-butoxy-naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-l-carboxylate; 20) - (3RS,4RS)-4-(4-fluorophenyl)-3-(4-(2-methoxy-benzyl-oxy)-naphthalen-2-ylmethoxy)-piperidine as a colourless resin, MS: 472 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-(2-methoxy-benzyloxy)-naphthalen-2-yl-methoxy)-piperidine-l-carboxylate; 21) - (3RS,4RS)-4-(4-fluorophenyl)-3-(4-(3-methoxy-benzyl-oxy)-naphthalen-2-ylmethoxy)-piperidine as a colourless solid, MS: 471 (M)+, from β-trimethyl-sllylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-(4-(3-methoxy-benzyloxy)-naphthalen-2-yl-methoxy)-piperidine-1-carboxylate; 22) - (3RS,4RS)-4-(4-fluorophenyl)-3-(4-(2-methoxy-benzyl- oxy)-naphthalen-2-ylmethoxy)-piperidine as a colourless oil, MS: 471 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-(4-methoxy-benzyloxy)-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate; 23) - (3RS,4RS)-4-(4-fluorophenyl)-3-(l-phenethyloxy-naph- thalen-2-ylmethoxy)-piperidine as a light yellow oil, MS: 456 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluoro- phenyl)-3-( 1 -phenethyloxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 24) - (3RS,4RS)-4-(4-fluorophenyl)-3-(4-phenethyloxy-naph- thalen-2-ylmethoxy)-piperidine as a colourless solid, MS: 456 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluoro- phenyl)-3-(4-phenethyloxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 25) - (3RS,4RS)-3-[4-(2-[1,3]dioxolan-2-yl-ethoxy)-naph-thalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine as a light yellow oil, MS: 451 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-3-[4-(2-[1,3]dioxolan-2-yl-ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine-l-carboxylate; 26) - (3RS,4RS)-3-[l-(2-[l ,3]dioxolan-2-yl-ethoxy)-naph-thalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine as a light yellow oil, MS: 452 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-3-[l -(2-[l ,3]dioxolan-2-yl-ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine-l-carboxylate; 27) - (3RS,4RS)-3-[4-(ben2o[1,3]dioxol-5-ylmethoxy)-naph-thalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine as a colour¬less resin, MS: 485 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-3-[4-(benzo[l ,3]dioxol-5-ylmethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine-l-carboxylate; 28) - (3RS,4RS)- 4-(2-cyclopropyl-ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine as a colourless solid, MS: 419 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-3-[4-(2- cyclopropyl-ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluoro-phenyl)-piperidine-l-carboxylate; 29) - (3RS,4RS)-4-(4-fluorophenyl)-3-[4-(2-hydroxy-ethoxy)- naphthalen-2-ylmethoxy]-piperidine as a colourless solid, MS: 395 (M)+, from β-trimethyl-silylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-[4-(2-hydroxy-ethoxy)-naphthalen-2-yl-methoxy]-piperidine-l-carboxylate; The compounds used as starting materials were prepared as follows: (a) 99 mg (0.20 mmol) of β-trimethyl-silylethyl (3RS,4RS)-4- (4-fluorophenyl)-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate were dissolved in 1 ml of dimethyl-formamide, treated with 69 mg (0.50 mmol) of anhydrous potassium carbonate and 19µl(43 mg, 0.30 mmol) of methyl iodide and stirred at room temperature for 4 hours. Subse¬quently, the mixture was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and finally the solvent was distilled off under reduced pressure. For purification, the crude product was chromatographed on silica gel with a 4:1 mixture of hexane and methylene chloride as the eluent. There were obtained 85 mg (83% of theory) of β- trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-methoxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow oil; MS: 509 (M)+. The following compounds were prepared in an analogous manner to the previously described procedure: - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(5- hydroxy-naphthalen-2-ylmethoxy)-piperidine-l -carboxylate and methyl iodide, β-trimethylsilylethyl (3RS,4RS)-4-(4-fluoro- phenyl)-3-(5-methoxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(6- hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and methyl iodide, β-trimethylsilylethyl (3RS,4RS)-4-(4-fluoro- phenyl)-3-(6-methoxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow oil; MS: 509 (M)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(7- hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and methyl iodide, β-trimethylsilylethyl (3RS,4RS)-4-(4-fluoro- phenyl)-3-(7-methoxy-naphthalen-2-yimethoxy)-piperidine-1-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(8- hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and methyl iodide, β-trimethylsilylethyl (3RS,4RS)-4-(4-fluoro- phenyl)-3-(8-methoxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4- hydroxy-naphthalen-2-ylmethoxy)-piperidine-l -carboxylate and 2-pyridylmethyl chloride, β-trimethylsilylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-[4-(pyridin-2-ylmethoxy)-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate as a light yellow oil; MS: 587 (M+H)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4- hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 3-pyridylmethyl chloride, β-trimethylsilylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-[4-(pyridin-3-ylmethoxy)-naphthalen-2-yl-methoxy]-piperidine-l-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4- hydroxy-naphthalen-2-ylmethoxy)-piperidine-l -carboxylate and 4-pyridylmethyl chloride, β-trimethylsilylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-[4-(pyridin-4-ylmethoxy)-naphthalen-2-yl-methoxy]-piperidine-l-carboxylate as a light yellow oil; MS: 587 (M+H)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4- hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and ally! bromide, β-trimethylsilylethyl (3RS,4RS)-3-(4-allyloxy- naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-l-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(6- hydroxy-naphthalen-2-ylmethoxy)-piperidine-l -carboxylate and allyl bromide, β-trimethylsilylethyl (3RS,4RS)-3-(6-allyloxy- naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-l-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4- hydroxy-naphthalen-2-ylmethoxy)-piperidine-l -carboxylate and iso-butyl bromide, β-trimethylsilylethyl (3RS,4RS)-4-(4-fluoro- phenyl)-3-(4-isobutoxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(l hydroxy-naphthalen-2-ylmethoxy)-piperidine-l -carboxylate and benzyl bromide, β-trimethylsilylethyl (3RS,4RS)-4-(4-fluoro- phenyl)-3-(1 -benzyloxy-naphthalen-2-ylmethoxy)-piperidine-l -carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4 hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and benzyl bromide, β-trimethylsilylethyl (3RS,4RS)-3-(4-benzyloxy naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-l-carboxylate as a light yellow oil; MS: 586 (M+H)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(7' hydroxy-naphthalen-2-ylmethoxy)-piperidine-l -carboxylate and benzyl bromide, β-trimethylsilylethyl (3RS,4RS)-3-(7-benzyloxy naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-1-carboxylate as a light yellow oil; MS: 585 (M)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(5 hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and benzyl bromide, 2-trimethylsilanyl-ethyl (3RS,4RS)-3-(5-benzyloxy-naphthalen-2-ylmethoxy)-4-(4-fluoro-phenyl)-piperidine-1-carboxylate as a colourless oil; MS: 585 (M)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(8' hydroxy-naphthalen-2-ylmethoxy)-piperidine-l -carboxylate and benzyl bromide, β-trimethylsilylethyl (3RS,4RS)-3-(8-benzyloxy naphthalen-2-ylmethoxy)-4-(4-fluorophenyl)-piperidine-1-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3- (4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate and 2-methoxyethyl bromide, 2-trimethylsilanyl-ethyl (3RS,4RS)-4-(4-fluoro-phenyl)-3-[4-(2-methoxy-ethoxy)- naphthalen-2-ylmethoxy]-piperidine-1-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4 hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 3-methoxypropyl chloride [J. Org. Chem. 16, 704(1951)], 2-tri-methylsilanyl-ethyl (3RS,4RS)-4-(4-fluoro-phenyl)-3-[4-(3-methoxy-propoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4 hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and butyl bromide, 2-trimethylsilanyl-ethyl (3RS,4RS)-3-(4-butyl-naphthalen-2-ylmethoxy)-4-(4-fluoro-phenyl)-piperidine-1-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4' hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 2-methoxybenzyl chloride, 2-trimethylsilanyl-ethyl (3RS,4RS)-4-(4-fluoro-phenyl)-3-[4-(2-methoxy-benzyloxy)-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 3-methoxybenzyl chloride, 2-trimethylsilanyl-ethyl (3RS,4RS)-4-(4-fluoro-phenyl)-3-[4-(3-methoxy-benzyloxy)-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow oil; MS: 61 5 (M)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4' hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 4-methoxybenzyl chloride, 2-trimethylsilanyl-ethyl (3RS,4RS)- 4-(4-fluoro-phenyl)-3-[4-(4-methoxy-benzyloxy)-naphthalen-2- ylmethoxy)-piperidine-1-carboxylate as a light yellow oil; MS: 616(M+H)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4- hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and phenethyl bromide, β-trimethylsilylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-(4-phenethyloxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(1-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and phenethyl bromide, 2-trimethylsilanyl-ethyl (3RS,4RS)-4-(4-fluoro-phenyl)-3-(1-phenethyloxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow oil; MS: 600 (M+H)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 2-(2-bromoethyl)-1,3-dioxolan, 2-trimethylsilanyl-ethyl (3RS,4RS)-3-[4-(2-[1,3]dioxolan-2-yl-ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluoro-phenyl)-piperidine-l -carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(l-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 2-(2-bromoethyl)-1,3-dioxolan, β-trimethylsilylethyl (3RS,4RS)- 3-[1 -(2-[1,3]dioxolan-2-yl-ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine-1-carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4- hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 3,4-methylenedioxybenzyl chloride, β-trimethyl-silylethyl (3RS,4RS)-3-[4-(ben2o[1,3]dioxol-5-ylmethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine-1 -carboxylate, which was used in crude form in the next step; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4- hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 2-cyclopropyl-ethyl chloride [Justus Liebigs Ann. Chem. 759. 132 (1972)], β-trimethylsilylethyl (3RS,4RS)-3-[4-(2-cyclopropyl- ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine-1-carboxylate as a light pink coloured oil; MS: 564 (M+H)+; - from β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and 2-(2-bromoethoxy)-tetrahydropyran, a mixture of β-trimethyl-silanylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-{4-[2-[(RS)- and (SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-naphthalen-2-yl-methoxy}-piperidine-1-carboxylate as a colourless oil; MS: 624 (M+H)+. Subsequent cleavage of the THP protecting group with a 1M solution of hydrogen chloride in methanol (10 minutes, room temperature) yielded β-trimethyl-silylethyl (3RS,4RS)-4-(4- fluorophenyl)-3-[4-(2-hydroxy-ethoxy)-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate as a colourless solid; MS: 540 (M+H)+. Example 1 5 (a) A solution of 63 mg (0.116 mmol) of β-trimethyl-silyl- ethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[4-(2-hydroxy-ethoxy)- naphthalen-2-ylmethoxy]-piperidine-1-carboxylate in 2 ml of methylene chloride was treated with 38 mg (0.58 mmol) of sodium cyanate. 44 µ l(67 mg, 0.58 mmol) of trifluoroacetic acid were added to this suspension at 0°C and the reaction mixture was stirred at room temperature for 2 hours. Subse¬ quently, the mixture was partitioned between methylene chloride and a 5% sodium hydrogen carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was distilled off under reduced pressure. The crude β-trlmethyl- silylethyl (3RS,4RS)-3-[4-(2-carbamoyloxy-ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluorophenyl)-piperidine-1-carboxylate obtained was used in the following step without further purification and characterization. (b) From the crude β-trimethyl-silylethyl (3RS,4RS)-3-[4-(2- carbamoyloxy-ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluoro- phenyl)-piperidine-1-carboxylate there was obtained by cleavage of the protecting group with tetrabutylammonium fluoride in tetrahydrofuran in analogy to the procedure described in Example 1 (e) (3RS,4RS)-3-[4-(2-carbamoyloxy-ethoxy)-naphthalen-2- ylnnethoxy]-4-(4-fluorophenyl)-piperidine as a light yellow oil; MS: 438 (M)+ Example 16 The following compounds were obtained in an analogous manner to that described in Example 1 (e) by cleavage of the protecting group with tetrabutylammonium fluoride in tetrahydrofuran: 1) - 4-(4-Fluorophenyl)-3-[4-[2-(pyridin-2-ylcarbamoyloxy)- ethoxy]-naphthalen-2-ylmethoxy]-piperidine as a colourless solid, MS: 395 [M-(PyNCO)]+, from β-trimethyl-silylethyl 4-(4- fluorophenyl)-3-[4-[2-(pyridin-2-ylcarbamoyloxy)-ethoxy]-naphthalen-2-ylmethoxy]-piperidine-l-carboxylate; 2) - (3RS,4RS)-3-[4-(2-benzoyloxy-ethoxy)-naphthalen-2- ylmethoxy]-4-(4-fluorophenyl)-piperidine as a colourless resin, MS: 500 (M+H)+, from β-trimethyl-silylethyl (3RS,4RS)-3-[4-(2- benzoyloxy-ethoxy)-naphthalen-2-ylmethoxy]-4-(4-fluoro-phenyl)-piperidine-1-carboxylate. The β-trimethyl-silylethyl carbamates used as the starting materials were obtained as follows: (a) A solution of 54 mg (0.10 mmol) of β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[4-(2-hydroxy-ethoxy)-naphthalen-2-ylmethoxy]-piperidine-l-carboxylate in 5 ml of toluene was treated with 30 mg (0.20 mmol) of 2-pyridylcarbonyl azide [Monatsh. Chem. 13, 397 (1912)] and 5 mg of 4-dlmethyl-aminopyridine. The solution was heated to reflux under argon for 2 hours. The mixture was cooled and the solvent was removed under reduced pressure. The residue was partitioned between methylene chloride and saturated sodium chloride solution, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (103 mg) was purified by chromatography on silica gel with a 1:2 mixture of ethyl acetate and hexane as the eluent. There were obtained 65 mg (99% of theory) of p-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[4-[2-(pyridin-2-ylcarbamoyloxy)-ethoxy]-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate as a colourless solid; MS: 660 (M+H)+. (b) A solution of 108 mg (0.20 mmol) of p-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[4-(2-hydroxy-ethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate in 2 ml of methylene chloride was treated with 56µ kl (41 mg, 0.40 mmol) of triethylamine. 36 µ l(42 mg, 0.30 mmol) of benzoyl chloride were added thereto. The reaction mixture was stirred at room temperature for 6 hours and at 50°C for one hour. Subsequently, the mixture was partitioned between methylene chloride and a 5% sodium hydrogen carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude p-trimethyl-silylethyl (3RS,4RS)-3-[4-(2-ben2oyloxy-ethoxy)-naphthalen-2-yl-methoxy]-4-(4-fluorophenyl)-piperidine-1-carboxylate was used directly in the next step. Example 17 The following compound was obtained in an analogous manner to that described in Example 5: The procedure was carried out as follows in analogy to Example 5(a)-(d): (a) From methyl salicylate there was obtained by introduction of the SEM group methyl 2-(2-trimethylsilylethoxymethoxy)-benzoate as a colourless oil; MS 224 [M-(C2H4 + Cl-l20)]+. (b) Reduction of methyl 2-(2-trimethylsilyl-ethoxymethoxy)-benzoate gave [2-(2-trimethylsilylethoxy-methoxy)-phenyl]-methanol as a light yellow oil; MS: 226 [M-(C2H4)]+. (c) Chlorination of [2-(2-trimethylsilylethoxy-methoxy)-phenyl]-methanol yielded l-chloromethyl-(2-trimethylsilyl-ethoxymethoxy)-benzene as a colourless oil; MS: 214, 216 [M-(C2H4 + CH20)]+ (d) Alkylation of β-trimethyl-silylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylic acid [Example 5 (g)] with 1-chloro-methyl-(2-trimethylsilyl-ethoxymethoxy)-benzene yielded β- trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)-3-[4-[2-(2-trimethylsilyl-ethoxymethoxy)-benzyloxy]-naphthalen-2-yl-methoxy]-piperidine-1-carboxylate as a colourless oil; MS: 749 (M+NH4)+; (e) From β-trimethylsilylethyl (3RS,4RS)-4-(4-fluorophenyl)- 3-[4-[2-(2-trimethylsilyl-ethoxymethoxy)-benzyloxy]- naphthalen-2-ylmethoxy]-piperidine-1-carboxylate by cleaving the β-trimethylsilylethyl carbamate with tetrabutylammonium fluoride in tetrahydrofuran in analogy to the procedure described in Example 5 there was obtained (3RS,4RS)-4-(4-fluorophenyl)-3-[4-[2-(2-trimethylsilyl-ethoxymethoxy)-benzyloxy]-naphthalen-2-ylmethoxy]-piperidine as a rose coloured oil; MS: 588 (M+H)+. (f) Cleavage of the SEM group from (3RS,4RS)-4-(4-fluoro- phenyl)-3-[4-[2-(2-trimethylsilyl-ethoxymethoxy)-benzyloxy]- naphthalen-2-ylmethoxy]-piperidine using a 2N solution of hydrogen chloride in methanol analogously to the procedure described in Example 5 (g) yielded (3RS,4RS)-4-(4-fluorophenyl)- 3-[4-[2-hydroxy-benzyloxy]-naphthalen-2-ylmethoxy]-piperidine as a colourless resin; MS: 458 (M+H)+. Example 18 The following compounds were obtained in an analogous manner to that described in Example 12 (d) by cleavage of the 2,2,2-trichloroethyl carbamate: 1) - (3RS,4RS)-4-(2-Fluorophenyl)-3-(naphthalen-2-yl-methoxy)-piperidine as a light yellow oil, MS: 336 (M+H)+, from 2,2,2-trichloroethyl (3RS,4RS)-4-(2-fluorophenyl)-3-(naph-thalen-2-ylmethoxy)-piperidine-l-carboxylate; 2) - (3RS,4RS)-4-(3-fluorophenyl)-3-(naphthalen-2-yl-methoxy)-piperldine as a light yellow oil, MS: 336 (M+H)+, from 2,2,2-trichloroethyl (3RS,4RS)-4-(3-fluorophenyl)-3-(naph-thalen-2-ylmethoxy)-piperidine-l-carboxylate; 3) - (3RS,4RS)-4-(3-hydroxyphenyl)-3-(naphthalen-2-yl-methoxy)-piperidine as a beige solid, MS: 333 (M)+, from 2,2,2-trichloroethyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[3-(2,2,2-trichloro-ethoxycarbonyloxy)-phenyl]-piperidine-l-carboxylate. The 2,2,2-trichloroethyl carbamates used as the starting materials were prepared as follows: (a) The following procedure was carried out in an analogous manner to that described in Example 1 (a)-(c): From 2-bromofluorobenzene and 1-benzyl-4-piperidone there was obtained 1-benzyl-4-(2-fluorophenyl)-piperidin-4-ol as a yellow oil; MS: 285 (M)+. Subsequent elimination yielded 1-benzyl-4-(2-fluorophenyl)-l,2,3,6-tetrahydro-pyridine as a light yellow oil; MS: 267 (M)+, Hydroboration subsequently gave (3RS,4RS)-l-benzyl-4-(2-fluorophenyl)-piperidin-3-ol as a colourless solid; MS: 285 (M)+. (b) In an analogous manner to that described in Example 1 (g), by alkylating (3RS,4RS)-1-benzyl-4-(2-fluorophenyl)-piperidin' 3-ol with 2-bromomethylnaphthalene there was obtained (3RS,4RS)-1-benzyl-4-(2-fluorophenyl)-3-(naphthalen-2-yl-methoxy)-piperidine as a yellow oil; MS: 284 (M-C11H9)+. By cleavage of the benzyl protecting group with 2,2,2-trichloroethyl chloroformate in an analogous manner to that described in Example 12 (c) there was obtained 2,2,2-trichloroethyl (3RS,4RS)-4-(2-fluorophenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a yellow oil; MS: 509 (M)+. (c) The following procedure was carried out in an analogous manner to that described in Example 1 (a)-(c): From 3-bromofluorobenzene and 1-benzyl-4-piperidone there was obtained 1-benzyl-4-(3-fluorophenyl)-piperidin-4-ol as a colourless solid; MS: 285 (M)+. Subsequent elimination yielded 1 -benzyl-4-(3-fluorophenyl)-l ,2,3,6-tetrahydro-pyridine as a light yellow oil; MS: 267 (M)+. Hydroboration subsequently gave (3RS,4RS)-1-benzyl-4-(3-fluorophenyl)-piperidin-3-ol as a colourless oil; MS: 285 (M)+. (d) In an analogous manner to that described in Example 1 (g), by alkylating (3RS,4RS)-1-benzyl-4-(3-fluorophenyl)-piperidin-3-ol with 2-bromomethylnaphthalene there was obtained (3RS,4RS)-1-benzyl-4-(3-fluorophenyl)-3-(naphthalen-2-ylmethoxy)-piperidine as a colourless oil; MS: 426 (M+H)+. By cleavage of the benzyl protecting group with 2,2,2-trichloroethyl chloroformate in an analogous manner to that described in Example 12 (c) there was obtained 2,2,2-trichloroethyl (3RS,4RS)-4-(3-fluorophenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a yellow oil; MS: 510 (M+H)+. (e) The following procedure was carried out in an analogous manner to that described in Example 1 (a)-(c): From 3-benzyloxy-iodobenzene [J. Chem. S°C . 2857 (1932)] and 1-benzyl-4-piperidone there was obtained 1-benzyl-4-(3-benzyloxy-phenyl)-piperidin-4-ol as a light yellow oil; MS: 373 (M)+. Subsequent elimination yielded 1-benzyl-4-(3-benzyloxy- phenyl)-1,2,3,6-tetrahydro-pyridine as a colourless solid; MS: 355 (M)+. Hydroboration subsequently gave (3RS,4RS)-l-benzyl-4-(3-benzyloxy-phenyl)-piperidin-3-ol as a colourless solid; MS: 373 (M)+ (f) In an analogous manner to that described in Example 1 (g), by alkylating (3RS,4RS)-1-benzyl-4-(3-benzyloxy-phenyl)-piperidin-3-ol with 2-bromomethylnaphthalene there was obtained (3RS,4RS)-1 -benzyl-4-(3-benzyloxy-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine as a colourless resin; MS: 514(M+H)+. (g) A solution of 250 mg (0.487 mmol) of (3RS,4RS)-1-benzyl-4-(3-benzyloxyphenyl)-3-(naphthalen-2-ylmethoxy)-piperidine in 1.1 ml of methylene chloride was treated at room temperature with 247 µl (236 mg, 1.946 mmol, 4 eq.) of N,N-dimethylaniline and 195 mg (1.46 mmol, 3.0 eq.) of aluminium trichloride and stirred at room temperature for 2.5 hours. Subsequently, the mixture was partitioned between methylene chloride and 5% sodium hydrogen carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product was purified by chromatography on silica gel with a 4:1 mixture of methylene chloride and hexane as the eluent. There were obtained 65 mg (32% of theory) of (3RS,4RS)-l-benzyl-4-(3-hydroxyphenyl)-3-(naphthalen-2-ylmethoxy)-piperidine as a beige coloured solid; MS: 423 (M)+ (h) In an analogous manner to that described in Example 12(c), by cleavage of the benzyl group with 2,2,2-trichIoroethyl chloroformate there was obtained 2,2,2-trichloroethyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[3-(2,2,2-trichloro-ethoxycarbonyloxy)-phenyl]-piperidine-l-carboxylate, which was used directly as the crude product in the next step. Example 19 In analogy to the procedure described in Example 2(e), by catalytically hydrogenating (3RS,4RS)-1-benzyl-4-(3-fluoro-phenyl)-piperidin-3-ol there was obtained (3RS,4RS)-4-(3-fluorophenyl)-piperidin-3-ol as a colourless solid; MS: 196 (M+H)+. Introduction of the B°C group in an analogous manner to that described in Example 1(f) yielded tert-butyl (3RS,4RS)-4-(3-fluorophenyl)-3-hydroxy-piperidine-1-carboxyiate as a colour¬less solid; MS: 296 (M+H)+. Subsequent alkylation with 4-benzyl-oxy-2-chloromethyl-naphthaline in analogy to the procedure described in Example 1 (g) gave tert-butyl (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(3-fluorophenyl)-piperidine-1-carboxylate as a colourless solid; MS: 541 (M)+. Cleavage of the B°C group using a solution of hydrogen chloride in methanol analogously to the procedure described in Example 1 (h) finally led to (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-yl-methoxy)-4-(3-fluorophenyl)-piperidine, which was obtained as a colourless solid; MS: 442 (M+H)+. The 4-benzyloxy-2-chloromethyl-naphthalene used as the starting compound was obtained as follows: (a) By alkylating ethyl 4-hydroxy-naphthalene-2-carboxylate [J. Agric. Chem S°C . Japan 24, 313 (1950)] with benzyl bromide in an analogous manner to that described in Example 14(a) there was obtained ethyl 4-benzyloxy-naphthalene-2-carboxylate as an almost colourless solid; MS: 216 (M)+. (b) Reduction of ethyl 4-benzyloxy-naphthalene-2-carboxylate analogously to Example 5(b) yielded (4-benzyloxy-naphthalen-2-yl)-methanol as a colourless solid; MS: 264 (M)+. (c) Chlorination of (4-benzyloxy-naphthalen-2-yl) [-methanol] using carbon tetrachloride analogously to Example 7(c) yielded 4-benzyloxy-2-chloromethyl-naphthalene as a colourless solid; MS: 282 (M)+ Example 20 The following compounds were obtained in an analogous manner to that described in Example 1 (h) by cleavage of the BOC group using a solution of hydrogen chloride in methanol: 1) - (3RS,4RS)-4-(4-Cyano-phenyl)-3-(naphthalen-2-yl-methoxy)-piperidine as a light yellow solid, MS: 342 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-cyano-phenyl)-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate; 2) - (3RS,4RS)-4-[4-(phenylsulphonylamino-methyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine as a colourless solid, MS: 485 (M-H)", from tert-butyl 4-[4-(phenylsulphonylamino-methyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 3) - (3RS,4RS)-4-[4-(4-methoxy-benzoylamino)-methyl]-phenyl-3-(naphthalen-2-ylmethoxy)-piperidine as a colourless resin, MS: 481 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(4-methoxy-benzoylamino)-methyl]-phenyl-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 4) - (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(phenyl-acetyl-aminomethyl)-phenyI]-piperidine as a colourless resin, MS: 465 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-yl-methoxy)-4-[4-(phenylacetylamino-methyl)-phenyl]-piperidine-1-carboxylate; 5) - (3RS,4RS)-4-[4-(benzoylamino-methyl)-phenyl]-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine as a light orange coloured solid, MS: 467 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(benzoylamino-methyl)-phenyl]-3-[4-(2-trimethylsilyl-ethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine-1 -carboxylate by simultaneous cleavage of the BOC and SEM groups analogously to that described in Example 3 and 5 (g). The BOC compounds used as the starting materials were prepared as follows: (a) A suspension of 20 mg (0.30 mmol) of activated zinc powder, 76 mg (1.17 mmol) of potassium cyanide, 52 mg (0.20 mmol) of triphenylphosphine and 74 mg (0.10 mmol) of bis(triphenylphosphine)-nickel(ll) dibromide in 2 ml of acetonitrile was heated at 60°C under argon for 5 minutes. 356 mg (1.00 mmol) of tert-butyl (3RS,4RS)-4-(4-bromophenyl) 3-hydroxy-piperidine-1-carboxylate in solid form were added thereto. The green suspension was stirred at 60°C under argon for 20 hours. The resulting dark brown suspension was filtered over Speedex and the insoluble material was washed with methylene chloride. The filtrate was partitioned between methylene chloride and 5% sodium hydrogen carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (416 mg) was purified by chromatography on silica gel with a 1:1 mixture of ethyl acetate and hexane as the eluent. There were obtained 168 mg (56% of theory) of tert-butyl (3RS,4RS)-4-(4-cyano-phenyl)-3-hydroxy-piperidine-1-carboxylate as a colourless solid; MS: 302 (M)+. (b) In analogy to the procedure described in Example 1 (g), by alkylating tert-butyl (3RS,4RS)-4-(4-cyano-phenyl)-3-hydroxy-piperidine-1-carboxylate with 2-bromomethylnaphthalene there was obtained tert-butyl (3RS,4RS)-4-(4-cyano-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow resin; MS: 443 (M+H)+. (c) A solution of 133 mg (0.301 mmol) of tert-butyl (3RS,4RS)-4-(4-cyano-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate in 0.5 ml of tetrahydrofuran was treated with 1.5 ml (1.5 mmol) of a 1M borane-tetrahydrofuran complex solution in tetrahydrofuran and the mixture was heated to reflux under argon for 6 hours. The reaction mixture was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (163 mg) was purified by chromatography on silica gel with a 14:1:0.1 mixture of methylene chloride, methanol and a 25% ammonia solution as the eluent. There were obtained 106 mg (79% of theory) of tert-butyl (3RS,4RS)-4-(4-aminomethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless resin; MS: 447 (M+H)+. (d) A solution of 47 mg (0.105 mmol) of tert-butyl (3RS,4RS)-4-(4-aminomethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate in 2 ml of methylene chloride was treated with 18 µl (12.7 mg, 0.126 mmol, 1.2 eq.) of triethylamine and cooled to 0°C . 15µl (20.4 mg, 0.116 mmol, 1.1 eq.) of benzenesulphonyl chloride were added dropwise, the mixture was warmed to room temperature and stirred for 1 hour. The reaction mixture was partitioned between methylene chloride and 5% sodium hydrogen carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. There were obtained 47 mg of crude tert-butyl (3RS,4RS)-4-[4-(phenylsulphonyl-amino-methyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, which was used in the following step without further purification and characterization. (e) In an analogous manner to the procedure described under (d), from tert-butyl (3RS,4RS)-4-(4-aminomethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate by acylation with β-anisoyi chloride there was obtained crude tert-butyl (3RS,4RS)-4-[4-(4-methoxy-benzoylamino)-methyl]-phenyl-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, which was used in the following step without further purification and characterization. (f) In an analogous manner to the procedure described under (d), from tert-butyl (3RS,4RS)-4-(4-aminomethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate by acylation with phenylacetyl chloride there was obtained crude tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(phenylacetyl- amino-methyl)-phenyl]-piperidine-l-carboxylate, which was used in the following step without further purification and character¬ization. (g) In an analogous manner to that described in Example 1 (g), by alkylating tert-butyl (3RS,4RS)-4-(4-cyano-phenyl)-3-hydroxy-piperidine-1-carboxylate with 2-chloromethyl-4-(β-trimethyl-silyl-ethoxymethoxy)-naphthalene there was obtained tert-butyl (3RS,4RS)-4-(4-cyano-phenyl)-3-[4-(2-trimethylsilyl-ethoxy-methoxy)-naphthalen-2-ylmethoxy]-piperidine-1 -carboxylate as a light yellow oil; MS: 530 [M-(C2H4+CH2O)]+. (h) In analogy to the procedure described under (c), by reducing the nitrile group in tert-butyl (3RS,4RS)-4-(4-cyano-phenyl)-3-[4-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate there was obtained tert-butyl (3RS,4RS)-4-(4-aminomethyl-phenyl)-3-[4-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-l-carboxylate as a light yellow oil; MS: 593 (M+H)+. (i) In analogy to the procedure described under (d), from tert-butyl (3RS,4RS)-4-(4-aminomethyl-phenyl)-3-[4-(2-trimethyl-silyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate by acylation with benzoyl chloride there was obtained crude tert-butyl (3RS,4RS)-4-[4-(benzoylamino-methyl)-phenyl]-3-[4-(2-trimethylsilyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate, which was used in the following step without further purification and characterization. Example 21 The following compounds were obtained in an analogous manner to that described in Example 1 (h) by cleavage of the BOC group using a solution of hydrogen chloride in methanol: 1) - (3RS,4RS)-4-(4-Chlorophenyl)-4-hydroxy-3-(4-methoxy-benzyloxy)-piperidine as a colourless solid, MS: 348 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-chlorophenyl)-4-hydroxy-3-(4-methoxy-benzyloxy)-piperidine-1-carboxylate; 2) - (3RS,4RS)-4-(4-chlorophenyl)-4-hydroxy-3-(naphthalen-2-ylmethoxy)-piperidine as a colourless solid, MS: 226, 228 [M-(CnH9)]+, from tert-butyl (3RS,4RS)-4-(4-chlorophenyl)-4-hydroxy-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate. The compounds used as the starting materials were prepared as follows: (a) A solution of 3.0 g (15.5 mmol) of 4-(4-chlorophenyl)-1,2,3,6-tetrahydro-pyridine in 20 ml of absolute dimethylform-amide was treated with 2.37 ml (1.72 g, 17.0 mmol) of triethyl-amine and cooled to 0°C. A solution of 3.7 g (17.0 mmol) of di-tert-butyl dicarbonate in 8 ml of absolute dimethylformamide was added dropwise at 0°C . The mixture was warmed to room temperature and stirred for 20 hours. The solvent was distilled off at 50-55°C at 0.1 mm Hg. Subsequently, the residue obtained was partitioned between methylene chloride and water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (5.0 g) was purified by chromatography on silica gel with a 95:5 mixture of methylene chloride and ethyl acetate as the eluent. There were obtained 4.5 g (99% of theory) of tert-butyl 4-(4-chlorophenyl)-! ,2,3,6-tetrahydro-pyridine-l-carboxylate as a colourless oil; MS: 236, 238 [M-(C4H9)]+. (b) A solution of 2.5 g (8.5 mmol) of tert-butyl 4-(4-chloro-phenyl)-l,2,3,6-tetrahydro-pyridine-l-carboxylate in 20 ml of acetone was treated with 0.425 ml (0.0085 mmol, 0.01 eq.) of osmium tetroxide solution (0.02M in tert-butanol) and 8.6 ml of hydrogen peroxide solution (30% in water) and the mixture was stirred at room temperature for 18 hours. The mixture was partitioned between ethyl acetate and water, the organic phase was washed with 10% sodium bisulphite solution and water, dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (2.2 g) was purified by chromatography on silica gel with a 3:1 mixture of methylene chloride and ethyl acetate as the eluent. There were obtained 544 mg (20% of theory) of tert-butyl (3RS,4RS)-4-(4-chloro-phenyl)-3,4-dihydroxy-piperidine-1-carboxylate as a colourless resin; MS; 270, 272 [M-(C4H9)]+. (c) A solution of 128 mg (0.392 mmol) of tert-butyl (3RS,4RS)-4-(4-chlorophenyl)-3,4-dihydroxy-piperidine-1-carboxylate in 1.5 m( of dimethyl sulphoxide was added dropwise to a suspension of 16 mg (0.4 mmol) of sodium hydride (60% dispersion in refined oil) in 3 ml of dimethyl sulphoxide. After 15 minutes a solution of 61 mg (0.39 mmol) of β-methoxybenzyl chloride in 1 ml of dimethyl sulphoxide was added dropwise at room temperature within 10 minutes and the mixture was stirred for 18 hours. Subsequently, the reaction mixture was partitioned between ethyl acetate and water, the organic phase was dried over magnesium sulphate and finally the solvent was removed under reduced pressure. The crude product (200 mg) was purified by chromatography on silica gel with a 3:1 mixture of hexane and ethyl acetate as the eluent. There were obtained (in addition to starting material and bisalkylated product) 63 mg (38% of theory) of tert-butyl (3RS,4RS)-4-(4-chIorophenyl)-4-hydroxy-3-(4-methoxy-benzyloxy)-piperidine-1-carboxylate as a colourless oil; MS: 448, 450 [M+H]+. (d) In an analogous manner to the procedure described under (c), by alkylating tert-butyl (3RS,4RS)-4-(4-chlorophenyl)-3,4-dihydroxy-piperidine-1-carboxylate with 2-bromomethyl-naphthalene there was obtained tert-butyl (3RS,4RS)-4-(4-chloropheny))-4-hydroxy-3-(naphthalen-2-ylmethoxy)-piperidlne-1-carboxylate as a light yellow oil; MS: 411, 413 [M- (C4H8)]+. Example 22 [a) 400 ml of a 1.2M solution of n-BuLi in hexane were added dropwise within 45 minutes to a solution, cooled to -70°C , of 112.5 g (0.48 mol) of 1,4-dibromoben2ene in 1200 ml of diethyl ether in such a manner that the temperature did not rise above -60°C . After completion of the addition the mixture was stirred at -70°C for 2.5 hours. Thereafter, a solution of 90.84 g (0.48 mol) of 1-benzyl-4-piperidone in 300 ml of ether was added dropwise at -70 to -65°C during one hour. After the dropwise addition the mixture was stirred at -70°C for 2 hours. For the working-up, the cold reaction mixture was poured into 1 200 ml of a 1 5% ammonium chloride solution, the mixture was transferred to a separating funnel and the organic phase was separated. The aqueous phase was extracted twice with ether and subsequently the combined organic phases were extracted twice with water and saturated sodium chloride solution. Then, the organic phase was dried over magnesium sulphate evaporated under reduced pressure, with the crude product separating as a yellowish solid. For purification, this was dissolved in hot methylene chloride, the solution was treated with hexane until turbidity began and cooled to room temperature while stirring. The resulting precipitate was filtered off under suction and dried. There were obtained 121,65 g (73% of theory) of 1-benzyl-(4-bromo-phenyl)-piperidin-4-ol as a yellowish solid; m.p.: 106°C , MS: 346, 348 (M+H)+. (b) A mixture of 121.6 g (0.35 mol) of 1-benzyl-4-(4-bromo- phenyl)-piperidin-4-ol and 121.6 g of β-toluenesulphonic acid monohydrate (0.64 mol) in 1200 ml of toluene was heated to reflux on a water separator for 4. hours. Subsequently, the reaction mixture was cooled to room temperature and adjusted to pH 10 with 3N sodium hydroxide solution. Thereafter, the mixture was extracted firstly with 200 ml and then with 500 ml of methylene chloride. The combined organic phases were washed twice with 100 ml of water each time, dried over magnesium sulphate and then evaporated under reduced pressure. There were obtained 109.1 g (99% of theory) of 1-benzyl-4-(4-bromo- phenyl)-1,2,3,6-tetrahydro-pyridine as a yellowish solid; MS: 328, 330 (M+H)+. (c) 16.9 g of sodium borohydride were added to a solution of 51.1 g (0.156 mol) of 1-benzyl-4-(4-bromo-phenyl)-1,2,3,6- tetrahydro-pyridine in 350 ml of dimethoxyethane and the reaction mixture was stirred at room temperature for 15 minutes. Thereafter, 95.2 ml of boron trifluoride etherate were added dropwise at 25-30°C during 30 minutes, the reaction mixture was subsequently stirred at room temperature for 2 hours. Thereafter, firstly a solution of 98.4 g of potassium hydroxide in 530 ml of water was slowly added dropwise and thereafter within 15 minutes 80.7 ml of a 30% hydrogen peroxide solution were added. Subsequently, the mixture was boiled under reflux for 2 hours. For the working-up, the cooled reaction mixture was filtered over Dicalit and this was rinsed with methylene chloride. The solution obtained was treated with 700 ml of methylene chloride, the organic phase was separated and then the aqueous phase was back-extracted with 300 ml of methylene chloride. The combined organic phases were washed twice with 200 ml of water each time, dried over magnesium sulphate and evaporated under reduced pressure. Crystallization of the crude product from acetone yielded 31 g (57% of theory) of (3RS,4RS)-1 -benzyl-4-(4-bromo-phenyl)-piperidin-3-ol as colourless crystals; m.p.: 125-1290C. (d) A Schlenk tube was charged under argon with 74.9 mg (0.29 mmol) of PdCl2(CH3CN)2, 168.0 mg (0.303 mmol) of 1,1'-bis(diphenylphosphino)ferr°C ene and 10 ml of methanol (distilled under argon) and the reaction mixture was stirred at room temperature for 30 minutes. The red-brown suspension was transferred under argon into a 185 ml steel aut°C lave fitted with a glass insert. Thereafter, 10.0 g (29 mmol) of (3RS,4RS)-1-benzyl-4-(4-bromo-phenyl)-piperidin-3-ol (pre-treated with active charcoal), 60 ml of methanol and 6 ml (43 mmol) of triethylamine (sic) were added. The aut°C lave was sealed, pressurized to 15 bar with carbon monoxide and the reaction mixture was stirred at 110° for 20 hours under constant pressure. After cooling the aut°C lave and releasing the gases the orange coloured reaction mixture was evaporated under reduced pressure. The solid, orange coloured residue was dissolved in 20 ml of methylene chloride, the solution was washed twice with 100 ml of 5% sodium carbonate solution each time and. respectively, with 100 ml of water and then evaporated under reduced pressure. For purification, the yellow-brown solid residue was chromatographed on silica gel using a 1:1 mixture of ethyl acetate and hexane as the eluent. There were obtained 7.74 g (82% of theory) of methyl (3RS,4RS)-4-(l-benzyl-3-hydroxy-piperidin-4-yl)-benzoate as a white solid; m.p.: 103-104°C ;MS:326(M+H)+. (e) A solution of 5.0 g (15.3 mmol) of methyl (3RS,4RS)-4-(1-ben2yl-3-hydroxy-piperidin-4-yl)-benzoate in 50 ml of tetra-hydrofuran was treated at room temperature with 720 mg (32.9 mmol) of lithium borohydride. Subsequently, the reaction mixture was heated to 60°C for 1 5 hours. For the working-up, the reaction mixture was treated with 20 ml of water while cooling with ice and thereafter extracted twice with 50 ml of ethyl acetate each time. The organic phases were combined, dried over sodium sulphate and evaporated under reduced pressure. The crude (3RS,4RS)-1 -benzyl-4-(4-hydroxymethyl-phenyl)-piperidine-3-ol obtained (Rf: 0.23, methylene chloride:methanol: ammonia = 95:5:0.1) was used in the following step without further purification. (f) A solution of 2.0 g (6.72 mmol) of (3RS,4RS)-1-benzyl-4-(4-hydroxymethyl-phenyl)-piperidin-3-ol in 100 ml of ethanol was hydrogenated at room temperature and 3 bar for 4 hours in the presence of 1.0 g of palladium oxide/charcoal (20%). For the working-up, the catalyst was filtered off under suction over Dicalit and the residue was washed twice with 50 ml of ethanol each time. The ethanol solution was evaporated under reduced pressure and the residue was chromatographed on silica gel using a 65:10:1 mixture of methylene chloride, methanol and ammonia as the eluent. There were obtained 1.1 g (79% of theory) of (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-piperidin-3-ol as a colourless solid; MS: 207 (M)+. (g) A solution of 1.10 g (5.31 mmol) of (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-piperidin-3-ol in 20 ml of dimethyl-formamide was treated at 0°C with 0.59 g (5.82 mmol) of triethylamine and 1.22 g (5.57 mmol) of di-tert-butyl dicarbonate and the mixture was stirred at room temperature for 15 hours. Subsequently, the dimethylformamide was distilled off in an oil pump vacuum and, for purification, the residue was chromatographed on silica gel using a 98:2 mixture of methylene chloride and methanol as the eluent. There were obtained 1.51 g (92% of theory) of tert-butyl (3RS,4RS)-3-hydroxy-4-(4-hydroxy-methyl-phenyl)-piperidine-1-carboxylate as a colourless foam; MS: 233 (M-C4H10O)+. (h) A solution of 1.50 g (5.14 mmol) of tert-butyl (3RS,4RS)-3-hydroxy-4-(4-hydroxymethyl-phenyl)-piperidine-l-carboxylate, 1.73 g (6.16 mmol) of triphenylchloromethane and 674 mg (6.68 mmol) of triethylamine in 20 ml of methylene chloride was stirred at room temperature for 5 hours. For the working-up, the reaction mixture was washed with 10 ml of water and 10 ml of saturated sodium hydrogen carbonate solution, the organic phase was dried over sodium sulphate and evaporated under reduced pressure. The crude product was chromatographed on silica gel using a 95:5 mixture of toluene and ethyl acetate as the eluent. There were obtained 2.08 g (77.5% of theory) of tert-butyl (3RS,4RS)-3-hydroxy-4-(4-trityloxymethyl-phenyl)-piperidine-1-carboxylate as a colourless foam; MS: 567 (M+NH4)+. (i) 290 mg (6.05 mmol) of sodium hydride (50% dispersion in refined oil) were added to a solution of 2.08 g (3.78 mmol) of tert-butyl (3RS,4RS)-3-hydroxy-4-(4-trityloxymethyl-phenyl)-piperidine-1-carboxylate and 1.0 g (4.54 mmol) of 2-bromo-methylnaphthalene in 30 ml of dimethylformamide and the reaction mixture was stirred at room temperature for 2 hours. For the working-up, the reaction mixture was evaporated in an oil pump vacuum, the residue was partitioned between 100 ml of saturated ammonium chloride solution and 100 ml of ethyl acetate and thereafter the separated aqueous phase was extracted twice with 50 ml of ethyl acetate each time. The combined ethyl acetate extracts were dried over sodium sulphate and evaporated under reduced pressure. For purification, the crude product was chromatographed on silica gel using a 4:1 mixture of methylene chloride and hexane as the eluent. There were obtained 2.27 g (87% of theory) of tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-(4-trityloxymethyl-phenyl)-piperidine-1-carboxylate as a colourless solid; MS: 707 (M+NH4)+. 0) A solution of 1.07 g (1.48 mmol) of tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-(4-trityloxymethyl-phenyl)-piperidine-1-carboxylate in 15 ml of methylene chloride was treated at room temperature with 2 ml of 2N hydrogen chloride in methanol and the mixture was stirred at room temperature for 15 minutes. Subsequently, the solution was poured into 30 ml of saturated sodium carbonate solution and this was extracted twice with 50 ml of ethyl acetate each time. The combined organic phases were dried over sodium sulphate and evaporated under reduced pressure. For purification, the crude product was chromatographed on silica gel using a 99:1 mixture of methylene chloride and methanol as the eluent. There were obtained 580 mg (82% of theory) of tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate as a colourless oil; MS: 447 (M)+. (k) A solution of 45 mg (0.1 mmol) of tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, 12 mg (0.12 mmol) of triethylamine and 12 mg (0.1 mmol) of pivaloyi chloride in 5 ml of methylene chloride was stirred at room temperature for 15 hours. For the working-up, the reaction solution was diluted with 10 ml of methylene chloride, then washed with 5 ml of water, dried over sodium sulphate and evaporated under reduced pressure. The residue was chromatographed on silica gel using a 4:1 mixture of hexane and ethyl acetate as the eluent. There were obtained 39 mg (73% of theory) of tert-butyl (3RS,4RS)-4-[4-(2,2-dimethyl-propionyloxymethyl)-phenyl]-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate as a colourless oil; MS: 549 (M+NH4)+. (I) A solution of 35 mg (0.07 mmol) of tert-butyl (3RS,4RS)-4-[4-(2,2-dimethyl-propionyloxymethyl)-phenyl]-3-(naphthalen-2- ylmethoxy)-piperidine-1-carboxylate in 2 ml of 2M hydrogen chloride in methanol was stirred at room temperature for 4.5 hours. Subsequently, the reaction solution was evaporated under reduced pressure. The residue was taken up in diethyl ether, with a part (15 mg, 49% of theory) of the (3RS,4RS)-4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzyl 2,2-dimethyl-propionate hydroc hloride being obtained in the form of white crystals; MS: 432 (M+H)+. Example 23 A solution of 1.10 g (1.59 mmol) of tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-(4-trityloxymethyl-phenyl)-piperidine-1-carboxylate in 50 ml of methanol was treated at room temperature with 30 ml of a 2M solution of hydrogen chloride in methanol and the mixture was stirred at room temperature for 4 hours. Subsequently, the solution was evaporated under reduced pressure and the residue was partitioned between 30 ml of saturated sodium carbonate solution and 50 ml of ethyl acetate. The aqueous phase was again extracted with 50 ml of ethyl acetate, thereafter the organic phases were combined, dried over sodium sulphate and evaporated under reduced pressure. For purification, the crude product was chromatographed on silica gel using a 90:10 mixture of methylene chloride and methanol as the eluent. There were obtained 462 mg (83% of theory) of (3RS,4RS)-[4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenyl}-methanol as a colourless solid; MS: 348 (M+H)+. Example 24 The following compounds were obtained in an analogous manner to that in Example 22 (I) by cleavage of the BOC group using acid 1) - (3RS,4RS)-4-[3-(Naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzyl benzoate as a colourless foam, MS: 452 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-benzoyloxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate; 2) - (3RS,4RS)-4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl) benzyl 3-methoxy-benzoate hydroc hloride as a colourless solid, MS: 482 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(3-methoxy-benzoyloxymethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperldine-1 -carboxylate; 3) - (3RS,4SR)-4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl) benzyl 3,5-dimethoxy-benzoate hydroc hloride as a colourless solid, MS: 512 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(3,5-dimethoxy-benzoyloxymethyl)-phenyl]-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate; 4) - (3RS,4RS)-4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzyl cyclohexanecarboxylate trifluoroacetate as a colourless solid, MS: 458 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-cyclohexanecarbonyloxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate using trifluoroacetic acid in methylene chloride; 5) - (4RS,3RS)-4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl) benzyl 2-chloro-benzoate trifluoroacetate as a colourless solid, MS: 486 (M+H)+, from tert-butyl (3RS,4RS)-[4-(2-chloro-benzoyloxymethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate using trifluoroacetic acid in methylene chloride; 6) - carbonic acid methyl ester (3RS,4RS)-4-(naphthalen-2-ylmethoxy-piperidin-4-yl)-benzyl ester hydroc hloride as a colourless oil, MS: 406 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-methoxycarbonyloxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy) piperidine-1 -carboxylate; 7) - (3RS,4RS)-4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzyl pyridine-4-carboxylate hydroc hloride as a yellow oil, MS: 453 (M+H)+, from (3RS,4RS)-4-(1-tert-butoxycarbonyl-3- naphthalen-2-ylmethoxy-piperidin-4-yl)-benzyl pyridine-4-carboxylate; 8) - (3RS,4RS)-4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl) benzyl pyrazine-2-carboxylate hydroc hloride as a colourless solid, MS: 454 (M+H)+, from (3RS,4RS)-4-[1-tert-butoxycarbonyl-3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzyl pyrazine-2-carboxylate; 9) - (3RS,4RS)-4-[3-(1-methoxy-naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzyl 2-chloro-benzoate trifluoroacetate as a colourless solid, MS: 516 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-chloro-benzoyloxymethyl)-phenyl]-3-(1-methoxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate using trifluoroacetic acid in methylene chloride; 10) - (3RS,4RS)-4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl) benzyl 4-hydroxy-benzoate hydroc hloride as a yellowish solid, MS: 468 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(4-hydroxy-benzoyloxymethyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate using trifluoroacetic acid in methylene chloride and simultaneous cleavage of the acetal group; 11) - (3RS,4RS)-4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzyl pyridin-2-yl-carbamate hydroc hloride as a colourless foam, Rf : 0.15 (methylene chloride:methanol ammonia = 90:10: 0.1), from tert-butyl (3RS,4RS)-3-(naphthalen-2-yl-methoxy)-4-[4-(pyridin-2-ylcarbamoyloxymethyl)-phenyl]-piperidine-1 -carboxylate; 12) - (3RS,4RS)-4-[4-(3-methoxy-propenyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine as a yellow oil, MS: 388 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(3-hydroxy-propenyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 13) - (3RS,4RS)-4-[4-(3-benzoyloxy-propenyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine as a yellow oil, MS: 478 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(3-benzoyloxy- propenyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 14) - 3-[4-[3-(naphthalen-2-ylmethoxy)-piperldln-4-yl]-phenyl]-propyl (3RS,4RS)-2-chloro-benzoate as a yellowish oil, MS: 514, 516 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-[3-(2-chloro-benzoyloxy)-propyl]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate. The starting materials were obtained as follows analogously to the procedure described in Example 22(k): (a) tert-Butyl (3RS,4RS)-4-(4-benzoyloxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil, MS: 552 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate and benzoyl chloride. (b) tert-Butyl (3RS,4RS)-4-[4-(3-methoxy-benzoyloxymethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless oil, MS: 582 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine- 1-carboxylate and 3-methoxybenzoyl chloride. (c) tert-Butyl (3RS,4RS)-4-[4-(3,5-dimethoxy-benzoyloxy-methyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil, MS: 612 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate and 3,5-dimethoxybenzoyl chloride. (d) tert-Butyl (3RS,4RS)-4-(4-cyclohexanecarbonyIoxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil, MS: 558 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine- 1-carboxylate and cyclohexanecarbonyl chloride. (e) tert-Butyl (3RS,4RS)-[4-(2-chloro-benzoyloxymethyl)- phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless oil, MS: 586 (M+H)+, from tert-butyl (3RS,4RS)-4-(4- hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine- 1-carboxylate and 2-chlorobenzoyl chloride. (f) tert-Butyl (3RS,4RS)-4-(4-methoxycarbonyloxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate as a colourless oil from tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate and methyl chloroformate. (g) A solution of 60 mg (0.13 mmol) of tert-butyl (3RS,4RS)-4-(4-hydroxymethyi-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, 16 mg (0.13 mmol) of isonicotinic acid, 34 mg (0.26 mmol) of ethyldiisopropylamine and 58 mg (0.13 mmol) of benzotriazol-l-yl-oxy-tris-(dimethylamino)-phosphonium hexafluorophosphate (BOP) in 5 ml of acetonitrile was stirred at room temperature for 2 hours. Subsequently, the reaction mixture was evaporated under reduced pressure and the residue, without further working-up, was chromatographed on silica gel using a 3:1 mixture of hexane and ethyl acetate as the eluent. There were obtained 15 mg (21% of theory) of (3RS,4RS)-4-(1-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzyl pyridine-4-carboxylate as a colourless solid; MS: 552 (M)+ (h) In an analogous manner to that described under (g) by condensing tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate and pyrazinecarboxylic acid using 1,1-carbonyldiimidazole as the condensation agent there was obtained 4-[1-tert-butoxycarbonyl-3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzyl (3RS,4RS)-pyrazine-2-carboxylate; MS: 554 (M+H)+. processing was carried out as follows in an analogous manner to that described in Example 22 (i)-(k): (i) Alkylation of methyl (3RS,4RS)-4-(l-benzyl-3-hydroxy-piperidin-4-yl)-benzoate with 2-bromomethyl-1-methoxy-naphthalene gave tert-butyl (3RS,4RS)-3-(1-methoxy-naphthalen-2-ylmethoxy)-4-(4-trityloxymethyl-phenyl)-piperidine-1-carboxylate as a colourless oil; MS: 720 (M+H)+. (j) Cleavage of the trityl group from tert-butyl (3RS,4RS)-3-(1-methoxy-naphthalen-2-ylmethoxy)-4-(4-trityloxymethyl-phenyl)-piperidine-1-carboxylate yielded tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(l -methoxy-naphthalen-2-yl-methoxy)-piperJdine-1-carboxylate as a colourless oil; MS: 478 (M+H)+ (k) Acylation of tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(1 -methoxy-naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate with 2-chlorobenzoyl chloride gave tert-butyl (3RS,4RS)-4-[4-(2-chloro-benzoyloxymethyl)-phenyl]-3-(1-methoxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil; MS: 615 (M+H)+. (I) In an analogous manner to that described under (g) by condensing tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate and 4-(2-trimethylsilanyl-ethoxymethoxy)-benzoic acid using N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide hydroc hloride (EDC) as the condensation agent there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-{4-[4-(2-trimethylsilanyl-ethoxy-methoxy)-benzoyloxymethyl]-phenyl}-piperidine-1-carboxylate; MS:715(M+NH4)+. The 4-(2-trimethylsilanyl-ethoxymethoxy)-benzoic acid was obtained as a colourless solid in an analogous manner to that described in Example 5 by reaction of methyl 4-hydroxybenzoate with 2-(trimethylsilyl)-ethoxymethyl chloride and subsequent basic saponification of the ester. (m) A solution of 57 mg (0.13 mmol) of tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)- piperidine-1-carboxylate, 20 mg (0.14 mmol) of pyridine-2-carbonyl azide [H.Saikachi and T.Kitgawa, Chem.Pharm.Bull. 25 (7), 1651-1657 (1977)] and 3 mg of 4-dimethylaminopyridine in 3 ml of toluene was heated to 90°C for 3 hours. Subsequently, the toluene was evaporated under reduced pressure, the residue was taken up in 15 ml of methylene chloride and the solution was washed with 5 ml of water. The organic phase was thereafter dried over sodium sulphate and evaporated under reduced pressure. The oily residue was taken up with a mixture of ether and hexane and crystallized. There were obtained 64 mg (88% of theory) of tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(pyridin-2-ylcarbamoyloxymethyl)-phenyl]-piperidine-1-carboxylate as a colourless solid; MS: 568 (M+H)+. (n) A Schlenk tube was charged under argon with 25.6 mg (0.114 mmol) of Pd(0Ac)2, 69.6 mg (0.229 mmol) of tri(o-tolyl)phosphine and 20 ml of DMF (distilled under argon) and the reaction mixture was stirred at room temperature for 1 5 minutes. A 200 ml sulphonation flask was charged under argon and while stirring with 8.15 g (22.9 mmol) of tert-butyl (3RS,4RS)-4-(4-bromo-phenyl)-3-hydroxy-piperidine-1-carboxylate [Example 25 (c)], 100 ml of DMF, 3.73 ml (34.3 mmol) of ethyl acrylate, 2.25 g (27.5 mmol) of sodium acetate and the yellow catalyst solution. The reaction mixture was stirred at 1 20°C for 6 hours. In order to complete the reaction, a solution of 5.1 mg Pd(0Ac)2 and 14.3 mg of tri(o-tolyl)phosphine in 5 ml of DMF was added after 5 hours. The dark reaction mixture was evaporated on a rotary evaporator. The grey solid residue was taken up in ether and the turbid solution was washed three times with water, dried over sodium sulphate and evaporated under reduced pressure. The yellow solid residue was chromatographed on 250 g of silica gel using a 2:1 mixture of hexane and ethyl acetate as the eluent. After crystallization from ethyl acetate there were obtained 6.66 g (77% of theory) of tert-butyl (3RS,4RS)-4-[4-(2-ethoxycarbonyl-vinyl)-phenyl]-3-hydroxy-piperidine-1-carboxylate as colourless crystals; MS: 376 (M+H)+. (o) Alkylation of tert-butyl (3RS,4RS)-4-[4-(2-ethoxycarbonyl-vinyl)-phenyl]-3-hydroxy-piperidine-1-carboxylate with 2-bromomethylnaphthalene analogously to the procedure described in Example 22(i) gave tert-butyl (3RS,4RS)-4-[4-(2-ethoxy-carbonyl-vinyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a light yellow resin; MS: 516 (M+H)+. (p) 5 ml (5 mmol) of a solution of diisobutylaluminium hydride (DIBAH) (1M in hexane) were added dropwise at -50°C to a solution of 698 mg (1.35 mmol) of tert-butyl (3RS,4RS)-4-[4-(2-ethoxycarbonyl-vinyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate in 15 ml of toluene and the mixture was stirred at -50°C for 30 minutes. Subsequently, the reaction mixture was treated dropwise at -50°C with 10 ml of ethanol and warmed to room temperature. For the working-up, the reaction mixture was treated with 20 ml of water and 20 ml of saturated potassium sodium tartrate solution while cooling with ice and thereafter extracted three times with 50 ml of ethyl acetate each time. The organic phases were combined, dried over sodium sulphate and evaporated under reduced pressure. The crude product was chromatographed on silica gel using a 6:4 mixture of hexane and ethyl acetate as the eluent. There were obtained 354 mg (55% of theory) of tert-butyl (3RS,4RS)-4-[4-(3-hydroxy-propenyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless solid; MS: 474 (M+H)+. (q) Acylation of tert-butyl (3RS,4RS)-4-[4-(3-hydroxy-propenyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate with benzoyl chloride analogously to the procedure described in Example 22(k) yielded tert-butyl (3RS,4RS)-4-[4-(3-benzoyloxy-propenyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless resin; MS: 578 (M+H)+. (r) A solution of 2.0 g (5.35 mmol) of tert-butyl (3RS,4RS)-4-[4-(2-ethoxycarbonyl-vinyl)-phenyl]-3-hydroxy-piperidine-1-carboxylate in 1 00 ml of ethanol was treated with 200 mg of palladium/charcoal (Type E101R) and hydrogenated at room temperature for 1 hour. Subsequently, the catalyst was filtered off and rinsed with ethanol. The filtrate was evaporated under reduced pressure and the light grey residue (1.97 g) was combined with those from three analogous hydrogenation batches (total 3.08 g). For purification, the crude product was chromato-graphed on silica gel using a 2:1 mixture of hexane and ethyl acetate as the eluent and thereafter crystallized from ethyl acetate/hexane. There were obtained 2.67 g (87% of theory) of tert-butyl (3RS,4RS)-4-[4-(2-ethoxycarbonyl-ethyl)-phenyl]-3-hydroxy-piperidine-1-carboxylate as colourless crystals; MS: 378 (M+H)+ (s) Analogously to the procedure described in Example 22(i), by alkylating tert-butyl (3RS,4RS)-4-[4-(2-ethoxycarbonyl-ethyl)-phenyl]-3-hydroxy-piperidine-1-carboxylic acid with 2-bromo-methylnaphthalene there was obtained tert-butyl (3RS,4RS)-4-[4-(2-ethoxycarbonyl-ethyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; MS: 518 (M+H)+. (t) Analogously to the procedure described in Example 22(e), by reducing tert-butyl (3RS,4RS)-4-[4-(2-ethoxycarbonyl-ethyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate using lithium borohydride there was obtained tert-butyl (3RS,4RS)-4-[4-(3-hydroxy-propyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless solid; MS: 476(M+H)+ (u) Acylation of tert-butyl (3RS,4RS)-4-[4-(3-hydroxy-propyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate with 2-chloro-benzoyl chloride analogously to the procedure described in Example 22(k) gave tert-butyl (3RS,4RS)-4-[4-[3-(2-chloro-benzoyloxy)-propyl]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless, amorphous solid; MS: 614.6, 616 (M+H)+ Example 25 (a) A mixture of 1.0 g (2.9 mmol) of (3RS,4RS)-1-benzyl-4-(4-bromo-phenyl)-piperidin-3-ol [Example 22(c)], 1.36 ml (10.2 mmol) of 2,2,2-trichloroethyl chloroformate and 0.90 g (12.6 mmol) of lithium carbonate in 20 ml of toluene was heated to 105°C for 18 hours. For the working-up, the cooled reaction mixture was poured into 200 ml of ice-water and subsequently extracted three times with 25 ml of ethyl acetate each time. The combined organic phases were dried over sodium sulphate and evaporated under reduced pressure. For purification, the crude material obtained was chromatographed on silica gel using a 2:3 mixture of methylene chloride and hexane as the eluent. There were obtained 1.3 g (76% of theory) of 2,2,2-trichloroethyl (3RS,4RS)-4-(4-bromo-phenyl)-3-(2,2,2-trichloro-ethoxy-carbonyloxy)-piperidine-1-carboxylate as a colourless solid; Rf. 0.17 (methylene chloride:hexane = 1:1), MS: 622, 624, 626 (M+NH4)+. (b) A mixture of 1.3 g (2.1 mmol) of 2,2,2-trichloroethyl (3RS,4RS)-4-(4-bromo-phenyl)-3-(2,2,2-trichloro-ethoxy-carbonyloxy)-piperidine-1-carboxylate 1.54 g of activated zinc in 20 ml of glacial acetic acid was stirred at room temperature for 5 hours. For the working-up, the zinc was filtered off, the residue was rinsed with glacial acetic acid and the solution was subsequently evaporated to dryness under reduced pressure. The residue was partitioned between 20 ml of saturated sodium carbonate solution and 30 ml of ethyl acetate, thereafter the separated aqueous phase was extracted twice with 30 ml of ethyl acetate each time. The combined organic phases were dried over sodium sulphate and evaporated under reduced pressure. Crystallization of the residue using a 1:2 mixture of ethyl acetate and hexane yielded 250 mg (46% of theory) of (3RS,4RS)-4-(4-bromo-phenyl)-piperidin-3-ol as a colourless solid; MS: 255, 257 (M)+. The mother liquor was purified by chromatography on silica gel using a 4:1 mixture of methylene chloride and methanol as the eluent. A further 101 mg (18% of theory) were obtained. (c) A solution of 351 mg (1.37 mmol) of (3RS,4RS)-4-(4-bromo-phenyl)-piperidin-3-ol in 12 ml of dimethylformamide was treated with 139 mg (1.37 mmol) of triethylamine and 300 mg (1.37 mg) of di-tert-butyl dicarbonate and the mixture was stirred at room temperature for 15 hours. Subsequently, the dimethylformamide was distilled off in an oil pump vacuum and the residue was crystallized from a 1:1 mixture of ether and hexane. There were obtained 318 mg (65% of theory) of tert-butyl (3RS,4RS)-4-(4-bromo-phenyl)-3-hydroxy-piperidine-1 -carboxylate as a colourless solid ; MS: 299, 301 (M-C4H8)+. Chromatography of the mother liquor on silica gel using a 98:2 mixture of methylene chloride and methanol as the eluent yielded a further 96 mg (19% of theory) of the product. (d) In an analogous manner to that described in Example 22(d), by carbonylating tert-butyl (3RS,4RS)-4-(4-bromo-phenyl)-3- hydroxy-piperidine-1-carboxylate using PdCl2(CH3CN)2 and 1,3- bis(diphenylphosphino)-propane as the catalyst in the presence of triethylamine under 10 bar of carbon monoxide at 100°C for 40 hours there was obtained tert-butyl (3RS,4RS)-3-hydroxy-4-(4-methoxycarbonyl-phenyl)-piperidine-1-carboxylate as white crystals; m.p.: 145.5-146°C , MS: 279 (M-C4H8)+. (e) In an analogous manner to that described in Example 22(i), by alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-(4-methoxy-carbonyl-phenyl)-piperidine-1-carboxylate with 2-bromomethyl-naphthalene there was obtained tert-butyl (3RS,4RS)-4-(4-methoxycarbonyl-phenyl)-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless oil; MS: 476 (M+H)+. (f) In an analogous manner to that described in Example 22(1), after cleavage of the BOC group from tert-butyl (3RS,4RS)-4-(4-methoxycarbonyl-phenyl)-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate there was obtained methyl (3RS,4RS)-4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzoate hydroc hloride as a colourless solid; MS: 344 (M-0CH3)+. Example 26 The following compounds were obtained in an analogous manner to that described in Example 22(1) by cleavage of the BOC group: 1) - (3RS,4RS)-[3-[3-(4-Benzyloxy-naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenyl}-methanol as a colourless amorphous powder, MS: 454 (M+H)+, from tert-butyl (3RS,4RS)-3-(4-benzyl-oxy-naphthalen-2-ylmethoxy)-4-(3-hydroxymethyl-phenyl)-piperidine-1 -carboxylate; 2) - (3RS,4RS)-3-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzyl benzoate hydroc hloride as a colourless solid, MS: 452 (M+H)+, from tert-butyl (3RS,4RS)-4-(3-benzoyloxymethyl-phenyl)-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate. The BOC derivatives used as the starting materials were obtained as follows: (a) In an analogous manner to that described in Example 22(a)-(d), starting from 3-bromophenyllithium and 1-benzyl-4-piperi-done there was obtained methyl (3RS,4RS)-3-(1-benzyl-3-hydroxy-piperidin-4-yl)-benzoate as a light yellow resin; MS: 325 (M)+ (b) The benzyl group was cleaved off from methyl (3RS,4RS)-3-(1-benzyl-3-hydroxy-piperidin-4-yl)-benzoate by catalytic hydrogenation in an analogous manner to that described in Example 2(e). The methyl (3RS,4RS)-3-(3-hydroxy-piperidine-4-yl)-benzoate was converted, without further purification and characterization, with di-tert-butyl dicarbonate analogously to Example 22(g) into tert-butyl (3RS,4RS)-3-hydroxy-4-(3-methoxycarbonyl-phenyl)-piperidine-1-carboxylate, MS: 304 (M-0CH3)+ (c) In an analogous manner to that described in Example 22(i), by alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-(3-methoxy-carbonyl-phenyl)-piperidine-1-carboxylate with 1-benzyloxy-3-chloromethylnaphthalene there was obtained tert-butyl (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(3-methoxycarbonyl-phenyl)-piperidine-1-carboxylate as a pale yellow amorphous powder; MS: 582 (M+H)+. (d) In an analogous manner to that described in Example 22(e), by reducing tert-butyl (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(3-methoxycarbonyl-phenyl)-piperidine-l-carboxylate with lithium borohydride there was obtained tert-butyl (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(3-hydroxymethyl-phenyl)-piperidine-1-carboxylate as a colourless solid; MS: 554 (M+H)+. (e) In an analogous manner to that described in Example 22(i), by alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-(3-methoxy-carbonyl-phenyl)-piperidine-1-carboxylate with 2-bromomethyl-naphthalene there was obtained tert-butyl (3RS,4RS)-4-(3-methoxycarbonyl-phenyl)-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless oil; MS: 493 (M+NH4)+. (f) In an analogous manner to that described in Example 22(e), by reducing tert-butyl (3RS,4RS)-4-(3-methoxycarbonyl-phenyl)-3-naphthalen-2-ylmethoxy-piperidine-1 -carboxylate with lithium borohydride there was obtained tert-butyl 4-(3-hydroxy-methyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil; MS: 448 (M+H)+. (g) In an analogous manner to that described in Example 22(l Example 27 The following compounds were obtained in an analogous manner to that described in Example 22(1) by cleavage of the BOC group: 1) - Methyl (3RS,4RS)-3-[3-(4-benzyloxy-naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzoate as a colourless amorphous powder, MS: 482 (M+H)+, from tert-butyl (3RS,4RS)-3-(4-benzyl-oxy-naphthalen-2-ylmethoxy)-4-(3-methoxycarbonyl-phenyl)-piperidine-1-carboxylate; 2) - methyl (3RS,4RS)-3-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzoate as a colourless oil, MS: 376 (M+H)+, from tert-butyl (3RS,4RS)-4-(3-methoxycarbonyl-phenyl)-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate. Example 28 By cleavage of the BOC group from 57 mg of crude tert-butyl (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(3-fluoromethyl-phenyl)-piperidine-l-carboxylate in an analogous manner to that described in Example 22 there was obtained (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(3-fluoromethyl-phenyl)-piperidine as a light yellow resin; MS: 456 (M+H)+ The tert-butyl (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(3-fluoromethyl-phenyl)-piperidine-l-carboxylate used as the starting material was prepared as follows: A solution of 18 mg (0.106 mmol) of diethylamino-sulphur trifluoride (DAST) in 1 ml of methylene chloride was cooled to -65°C and a solution of 56 mg (0.101 mmol) of tert-butyl (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(3-hydroxymethyl-phenyl)-plperidine-l-carboxylate in 1 ml of methylene chloride was added dropwise thereto at -60°C to -650c within 3 minutes. The resulting yellow solution was warmed to room temperature and stirred for one hour. Sub¬sequently, the mixture was partitioned between methylene chloride and 5% sodium hydrogen carbonate solution, the organic phase was dried over magnesium sulphate and finally the solvent was distilled off under reduced pressure. There were obtained 57 mg of crude tert-butyl (3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(3-fluoromethyl-phenyl)-piperidine- 1-carboxylate, which was used in the next step without further purification and characterization. Example 29 (a) In an analogous manner to that described in Example 22(a), starting from 1-benzyl-4-piperidone and 2-[2-(4-bromo-phenyl)-ethoxy]-tetrahydropyran there was obtained (RS)-1-benzyl-4-[4-[2-(tetrahydro-pyran-2-yloxy)-ethyl]-phenyi]-piperidin-4-ol as a yellow oil; MS: 396 (M+H)+. (b) A solution of 78 g (197 mmol) of (RS)-1-benzyl-4-[4-[2-(tetrahydro-pyran-2-yloxy)-ethyl]-phenyl]-piperidin-4-ol in 400 ml of methanol was treated with 470 ml of 2N hydroc hloric acid and stirred at room temperature for 5 hours. For the working-up, the reaction solution was poured into 1500 ml of saturated sodium hydrogen carbonate solution and subsequently extracted three times with 1000 ml of ethyl acetate each time. The combined organic phases were dried over sodium sulphate and evaporated under reduced pressure. For purification of the crude substance, a flash chromatography on silica gel using a 95:5 mixture of methylene chloride and methanol as the eluent was carried out. There were obtained 51.6 g (84% of theory) of 1-benzyl-4-[4-(2-hydroxy-ethyl)-phenyl]-piperidin-4-ol as a yellowish solid; MS: 312 (M+H)+. (c) In an analogous manner to that described in Example 22(b), by an elimination reaction from 1-benzyl-4-[4-(2-hydroxy-ethyl)-phenyl]-piperidin-4-ol using β-toluenesulphonic acid there was obtained 2-[4-(1-benzyl-1,2,3,6-tetrahydro-pyridin-4-yl)-phenyl]-ethanol as a colourless oil; MS: 293 (M)+. (d) In an analogous manner to that described in Example 22(c), from 2-[4-(1 -benzyl-1,2,3,6-tetrahydro-pyridin-4-yl)-phenyl]-ethanol by hydroboration there was obtained (3RS,4RS)-1-benzyl-4-[4-(2-hydroxy-ethyl)-phenyl]-piperidin-3-ol as a colourless oil; MS: 311 (M)+. (e) In an analogous manner to that described in Example 2(e) and Example 22(g), by catalytically hydrogenating (3RS,4RS)-1-ben2yl-4-[4-(2-hydroxy-ethyl)-phenyl]-piperidin-3-ol there was obtained (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-piperidin-3-ol, which, without further purification and characterization, was converted with di-tert-butyl dicarbonate into tert-butyl (3RS,4RS)-3-hydroxy-4-[4-(2-hydroxy-ethyl)-phenyl]-piperidine-1-carboxylate; colourless oil, MS: 322 (M+H)+. (f) In an analogous manner to that described in Example 22(h), from tert-butyl (3RS,4RS)-3-hydroxy-4-[4-(2-hydroxy-ethyl)-phenyl]-piperidine-1-carboxylate by introduction of the trityl group there was obtained tert-butyl (3RS,4RS)-3-hydroxy-4-[4-(2-trityloxy-ethyl)-phenyl]-piperidine-1-carboxylate as a colourless foam; MS: 581 (M+NH4)+. (g) In an analogous manner to that described in Example 22(1), from tert-butyl (3RS,4RS)-3-hydroxy-4-[4-(2-trityloxy-ethyl)-phenyl]-piperidine-l-carboxylate by alkylation with 2-bromo-methylnaphthalene there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-trityloxy-ethyl)-phenyl]-piperidine-1-carboxylate as a colourless oil; MS: 721 (M+H)+. (h) In an analogous manner to that described In Example 22G), from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-trityloxy-ethyl)-phenyl]-piperidine-1-carboxylate by cleavage of the trityl group there was obtained tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless solid; MS: 462 (M+H)+. (i) In an analogous manner to that described in Example 22(k), by acylating tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate with cyciopropanecarbonyl chloride there was obtained tert-butyl (3RS,4RS)-4-[4-(2-cyclopropylcarbonyloxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless oil; MS: 572 (M+H)+. (j) In an analogous manner to that described in Example 22(1), by cleavage of the BOC group from tert-butyl (3RS,4RS)-4-[4-(2-cyclopropylcarbonyloxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate using trifluoroacetic acid in methylene chloride there was obtained (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl cyclo-propanecarboxylate trifluoroacetate as a white solid; MS: 430 (M+H)+. Example 30 The following compound was obtained in an analogous manner to that described in Example 23 by simultaneous cleavage of the BOC and trityl groups: - (3RS,4RS)-2-{4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenyl}-ethanol hydroc hloride as a white powder, MS: 362 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-trityloxy-ethyl)-phenyl]-piperidine-1-carboxylate. Example 31 The following compounds were obtained in an analogous manner to that in Example 22 (I) by cleavage of the BOC group using acid: 1) - (3RS,4RS)-2-[4-(3-Naphthalen-2-ylmethoxy-piperidin-4- yl)-phenyl]-ethyl benzoate hydroc hloride as a white solid, MS: 466 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-benzoyloxy- ethyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1- carboxylate; 2) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4- yl)-phenyl]-ethyl 3-methoxy-benzoate hydroc hloride as a colour¬ less oil, MS: 496 (M+H)+, from tert-butyl (3RS,4RS)-4-{4-[2-(3- methoxy-benzoyloxy)-ethyl]-phenyl}-3-(naphthalen-2-yl- methoxy)-piperidine-1-carboxylate; 3) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl 2-methoxy-benzoate hydroc hloride as a colour¬less solid, MS: 496 (M+H)+, from tert-butyl (3RS,4RS)-4-{4-[2-(2-methoxy-benzoyloxy)-ethyl]-phenyl}-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate; 4) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl benzyloxy-acetate hydroc hloride as a colourless solid, MS: 510 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-benzyloxyacetoxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1 -carboxylate; 5) - (3RS,4RS)-2-[4-(3-naphthalen-2-yl-methoxy)-piperidin-4-yl]-phenyl]-ethyl (4-methoxy-phenyl)-acetate trifluoroacetate as a colourless solid, MS: 510 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-[2-[(4-methoxy-phenyI)-acetoxy]-ethyl]-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1 -carboxylate using trifluoroacetic acid in methylene chloride; 6) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl cyclohexanecarboxylate trifluoroacetate as a colourless solid, MS: 472 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-cyclohexylcarbonyioxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate using trifluoroacetic acid in methylene chloride; 7) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl 2,6-dichloro-benzoate trifluoroacetate as a colourless solid (sic), MS: 534 (M+H)+, from tert-butyl (3RS,4RS)-4-{4-[2-(2,6-dichloro-benzoyloxy)-ethyl]-phenyl}-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate using trifluoroacetic acid in methylene chloride; 8) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl 2,6-dimethoxy-benzoate trifluoroacetate as a colourless solid, MS: 526 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-[2-(2,6-dimethoxy-benzoyloxy)-ethyl]-phenyI]-3-naphthalen- 2-ylmethoxy-piperidine-l-carboxylate using trifluoroacetic acid in methylene chloride; 9) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl 2-acetoxy-benzoate trifluoroacetate as a colourless solid, MS: 524 (M+H)+, from tert-butyl (3RS,4RS)-[4-[4-[2-(2-acetoxy-benzoyloxy)-ethyl]-phenyl]-3-naphthalen-2-ylmethoxy-piperidine]-1-carboxylate using trifluoroacetic acid in methylene chloride; 10) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl 2-chloro-benzoate trifluoroacetate as a colourless solid, MS: 500 (M+H)+, from tert-butyl (3RS,4RS)-[4-[2-(2-chloro-benzoyloxy)-ethyl]-phenyl]-3-naphthalen-2-yl-methoxy-piperidine-1-carboxylate using trifluoroacetic acid in methylene chloride; 11) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl pyridin-2-yl-carbamate hydroc hloride as a colourless foam, MS: 482 (M+H)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-pyridin-2-ylcarbamoyloxy-ethyl)-phenyl]-piperidine-1-carboxylate; 12) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl phenyl-carbamate hydroc hloride as a colourless solid, MS: 598 (M+H)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-phenylcarbamoyloxy-ethyl)-phenyl]-piperidine-1 -carboxylate; 13) - (3RS,4SR)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl pyridine-3-carboxylate hydroc hloride as a colourless solid, MS: 467 (M+H)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-pyridin-3-ylcarbonyloxy-ethyl)-phenyl]-piperidine-1-carboxylate; 14) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl pyridlne-2-carboxylate as a colourless oil, MS: 467 (M+H)+, from 2-{4-[1-tert-butoxycarbonyl-3- (naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenyl}-ethyl (3RS,4RS)-pyridine-2-carboxylate; 15) - (3RS,4RS)-2-[4-(3-naphthalen-2-yimethoxy-piperidin-4-yl)-phenyl]-ethyl thiophene-3-carboxylate trifluoroacetate as a colourless solid, MS: 472 (M+H)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-thiophen-3-ylcarbonyloxy-ethyl)-phenyl]-piperidine-l-carboxylate using trifluoroacetic acid in methylene chloride; 16) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl thiophen-2-ylacetate trifluoroacetate as a colourless solid, MS: 486 (M+H)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-thiophen-3-ylacetoxy-ethyl)-phenyl]-piperidine-1-carboxylate using trifluoroacetic acid in methylene chloride; 17) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-ethyl imidazole-2-carboxylate trifluoroacetate as a colourless solid, MS: 456 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-imidazol-2-ylcarbonyloxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate using trifluoroacetic acid in methylene chloride; 18) - (3RS,4RS)-2-[4-[3-(4-benzyloxy-naphthalen-2-yi-methoxy)-piperidin-4-yl]-phenyl]-ethyl benzoate hydroc hloride as a yellowish solid, MS: 572 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-benzyloxy-ethyl)-phenyl-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-piperidine-1-carboxylate. The following starting materials were obtained analogously to the procedure described in Example 22 (k): (a) tert-Butyl (3RS,4RS)-4-[4-(2-benzoyloxy-ethyl)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colour¬less oil, MS: 583 (M+NH4)+, from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate and benzoyl chloride; (b) tert-butyl (3RS,4RS)-4-{4-[2-(3-methoxy-benzoyloxy)-ethyl]-phenyl}-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate as a colourless oil, MS: 593 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate and 3-methoxybenzoyl chloride; (c) tert-butyl (3RS,4RS)-4-{4-[2-(2-methoxy-benzoyloxy)-ethyl]-phenyl}-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil, Rf : 0.35 (SiOz, hexane:ethyl acetate = 2:1), from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate and 2-methoxybenzoyl chloride; (d) tert-butyl (3RS,4RS)-4-[4-(2-benzyloxyacetoxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-l-carboxylate as a colourless oil, MS: 627 (M+NH4)+, from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate and benzyloxyacetyl chloride; (e) tert-butyl (3RS,4RS)-4-[4-[2-[(4-methoxy-phenyl)-acetoxy]-ethyl]-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless oil, MS: 627 (M+NH4)+, from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate and 4-methoxyphenylacetyl chloride; (f) tert-butyl (3RS,4RS)-4-[4-(2-cyclohexylcarbonyloxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless oil, MS: 572 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate and cyclohexanecarbonyl chloride; (g) tert-butyl (3RS,4RS)-4-{4-[2-(2,6-dichloro-benzoyloxy)-ethyl]-phenyl}-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil, MS: 651 (M+NH4)+, from tert- butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-l-carboxylate and 2,6-dichlorobenzoyl chloride; (h) tert-butyl (3RS,4RS)-4-[4-[2-(2,6-dimethoxy-benzoyloxy)-ethyl]-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-l-carboxyl-ate as a colourless amorphous solid, MS: 643 (M+NH4)+, from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate and 2,6-dimethoxybenzoyl chloride; (i) tert-butyl (3RS,4RS)-[4-[4-[2-(2-acetoxy-benzoyloxy)-ethyl]-phenyl]-3-naphthalen-2-ylmethoxy-piperidine]-1-carboxylate as a colourless oil, MS: 641 (M+NH4)+, from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate and 0-acetylsalicyloyl chloride; 0) tert-butyl (3RS,4RS)-[4-[2-(2-chloro-benzoyloxy)-ethyl]-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless oil, MS: 617 (M+NH4)+; from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate and 2-chlorobenzoyl chloride; (k) In an analogous manner to that described in Example 24(m), by reacting tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-l-carboxylate with pyridine-2-carbonyl azide there was obtained tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-pyridin-2-ylcarbamoyloxy-ethyl)-phenyl]-piperidine-l -carboxylate as colourless crystals, MS: 582 (M+H)+. (I) In an analogous manner to that described in Example 24(m), by reacting tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-l-carboxylate with phenyl is°C yanate there was obtained tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-phenylcarbamoyloxy-ethyl)- phenyl]-piperidine-l-carboxylate as a colourless oil, MS: 481 (M+H)+. (m) In an analogous manner to that described in Example 24(g), by condensing tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-l -carboxylate and nicotinic acid there was obtained tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-pyridin-3-ylcarbonyloxy-ethyl)-phenyl]-piperidine-1-carboxylate as a colourless oil, MS: 567 (M+H)+. (n) In an analogous manner to that described in Example 24(g), by condensing tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1 -carboxylate and pyridine-2-carboxylic acid using 1,1-carbonyldiimidazole as the condensation agent there was obtained 2-{4-[1-tert-butoxy-carbonyl-3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenyl}-ethyl (3RS,4RS)-pyridine-2-carboxylate as a colourless oil, MS: 467(M+H)+ (o) In an analogous manner to that described in Example 24(g), by condensing tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1 -carboxylate and thiophene-3-carboxylic acid using 1,1-carbonyldiimidazole as the condensation agent there was obtained tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-thiophen-3-ylcarbonyloxy-ethyl)-phenyl]-piperidine-1-carboxylate as white crystals, MS: 572 (M+H)+ (p) In an analogous manner to that described in Example 24(g), by condensing tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyi]-3-naphthalen-2-ylmethoxy-piperidine-1 -carboxylate and 3-thiopheneacetic acid using 1,1-carbonyldiimidazole as the condensation agent there was obtained tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-thiophen-3-ylacetoxy-ethyl)-phenyl]-piperidine-1-carboxylate as a colourless solid, MS: 603 (M+NH4)+. (q) In an analogous manner to that described in Example 24(g), by condensing tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1 -carboxylate and imidazole-2-carboxylic acid using 1,1-carbonyldiimidazole as the condensation agent there was obtained tert-butyl (3RS,4RS)-4-[4-(2-imidazol-2-ylcarbonyloxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate as a colourless solid, MS: 556(M+H)+ The following procedure was carried out in an analogous manner to that described in Example 22(i)-(k): (r) Alkylation of tert-butyl (3RS,4RS)-3-hydroxy-4-[4-(2-trityloxy-ethyl)-phenyl]-piperidine-1-carboxylate with 1-benzyloxy-3-chloromethyl-naphthalene gave tert-butyl [3RS,4RS)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-[4-(2-trityloxy-ethyl)-phenyl]-piperidine-1-carboxylate as a colourless Dil, MS: 827 (M+NH4)+. [s) Cleavage of the trityl group from tert-butyl (3RS,4RS)-3-;4-benzyloxy-naphthalen-2-ylmethoxy)-4-[4-(2-trityloxy-ethyl)-Dhenyl]-piperidine-1-carboxylate yielded tert-butyl (3RS,4RS)-3-;4-benzyloxy-naphthalen-2-ylmethoxy)-4-[4-(2-hydroxy-ethyl)-)henyl]-piperidine-1-carboxylate as a colourless oil, MS: 568 :M+H)+. t) Acylation of tert-butyl (3RS,4RS)-3-(4-benzyloxy-iaphthalen-2-ylmethoxy)-4-[4-(2-hydroxy-ethyl)-phenyl]-)iperidine-1-carboxylate with benzoyl chloride gave (3RS,4RS)-1-[4-(2-benzyloxy-ethyl)-phenyl-3-(4-benzyloxy-naphthalen-2-'lmethoxy)-piperidine-1-carboxylate as a colourless oil, MS: 689 M+NH4)+. Example 32 The following compounds were obtained in an analogous nanner to that described in Example 22(1) by cleavage of the BOC [roup using acid: 1) - (3RS,4RS)-3-Naphthalen-2-ylmethoxy-4-(4-naphthalen-2-ylmethoxymethyl-phenyl)-piperidine hydroc hloride as a colourless solid, MS: 488 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(naphthalen-2-ylmethoxy-methyl)-phenyl]-piperidine-1-carboxylate; 2) - (3RS,4RS)-4-[4-(4-methoxy-phenoxymethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine as a yellow foam, MS: 454 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(4-methoxy-phenoxy-methyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate; 3) - (3RS,4RS)-3-(1-methoxy-naphthalen-2-ylmethoxy)-4-[4-(2-phenoxy-ethyl)-phenyl]-piperidine trifluoroacetate as a colourless oil, MS: 468 (M+H)+, from tert-butyl (3RS,4RS)-3-(1-methoxy-naphthalen-2-ylmethoxy)-4-[4-(2-phenoxy-ethyl)-phenyl]-piperidine-l-carboxylate using trifluoroacetic acid in methylene chloride; 4) - (3RS,4RS)-4-[4-(2-methoxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy]-piperidine as a colourless solid, MS: 376 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-methoxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy]-piperidine-l-carboxylate. The BOC derivatives use as the starting materials were prepared as follows: (a) In an analogous manner to that described in Example 22(i), by alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-(4-hydroxy-methyl-phenyl)-piperidine-1-carboxylate with 2-bromomethyl-naphthalene there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(naphthalen-2-ylmethoxy-methyl)-phenyl]-piperidine-1-carboxylate as a colourless oil, Rf: 0.31 (SiOz, hexane:ethyl acetate = 2:1). b) A solution of 200 mg (0.45 mmol) of tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)- piperidine-1-carboxylate in 10 ml of tetrahydrofuran was treated in sequence with 143 mg (0.58 mmol) of triphenylphosphine, 94 mg (0.58 mmol) of diethylazo dicarboxylate and 166 mg (1.35 mmol) of hydroquinone monomethyl ether and the reaction mixture was stirred at room temperature for 15 hours. For the working-up, the reaction mixture was diluted with 20 ml of methylene chloride and extracted with 20 ml of saturated sodium carbonate solution. The organic phase was dried over sodium sulphate and evaporated under reduced pressure. For purification, the crude product was chromatographed on silica gel using methylene chloride as the eluent. There were obtained 245 mg of colourless oil which contained tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate in addition to tert-butyl (3RS,4RS)-4-[4-(4-methoxy-phenoxymethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate, Rf: 0.08 (methylene chloride). The following procedure was carried out in an analogous manner to that described in Example 22(i)-0): (c) Alkylation of tert-butyl (3RS,4RS)-3-hydroxy-4-[4-(2-trityloxy-ethyl)-phenyl]-piperidine-l-carboxylate with 2-bromomethyl-1-methoxy-naphthalene gave tert-butyl (3RS,4RS)-3-(l-methoxy-naphthalen-2-ylmethoxy)-4-[4-(2-trityloxy-ethyl)-phenyl]-piperidine-l-carboxylate from which, after cleavage of the trityl group there was obtained tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-(l-methoxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate and, after reaction with phenol, analogously to the procedure described under (b), tert-butyl (3RS,4RS)-3-(l-methoxy-naphthalen-2-ylmethoxy)-4-[4-(2-phenoxy-ethyl)-phenyl]-piperidine-l-carboxylate as a colourless oil; Rf: 0.34 (SiOz, hexane:ethyl acetate = 2:1). (d) In an analogous manner to that described in Example 22(i) by alkylating tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-l-carboxylate with methyl iodide there was obtained tert-butyl (3RS,4RS)-4- [4-(2-methoxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate as a colourless oil; MS: 493 (M+NH4)+. Example 33 The following compounds were obtained in an analogous manner to that described in Example 22 (I) by cleavage of the BOC group by means of acid: 1) - (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-phenyl-sulphanyl-ethyl)-phenyl]-piperidine hydroc hloride as white crystals, MS: 454 (M+H)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-phenylsulphanyl-ethyl)-phenyl]-piperidine-l-carboxylate; 2) - a mixture of (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-[(RS)- and -[(SR)-2-phenylsulphinyl-ethyl]-phenyl]-piperidine as a colourless amorphous solid, MS: 470 (M+H)+, from a mixture of tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-[(RS)- and -[(SR)-2-phenylsulphinyl-ethyl]-phenyl]-piperidine-1-carboxylate; 3) - (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-phenyl-sulphonyl-ethyl)-phenyl]-piperidine hydroc hloride as white crystals, MS: 486 (M+H)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-phenylsulphonyl-ethyl)-phenyl]-piperidine-1-carboxylate; 4) - (3RS,4RS)-4-[4-(2-benzothiazol-2-ylsulphanyI-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine as a colourless foam, MS: 511 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-benzothiazol-2-ylsulphanyl-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate; 5) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzylsulphanyl]-benzothiazole as a yellow foam, MS: 497 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(benzothiazol-2-yl- sulphanylmethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate; 6) - (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(1-phenyl-1 H-tetra2ol-5-ylsulphanylmethyl)-phenyl]-piperidine hydroc hloride as a colourless oil, MS: 508 (M+H)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(1 -phenyl-1 H-tetrazol-5-ylsulphanylmethyl)-phenyl]-piperidine-l-carboxylate; 7) - (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenoxy-ethyl)-phenyl]-piperidine as a yellowish foam, MS: 438 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenoxy-ethyl)-phenyl]-piperidine-l-carboxylate. The BOC derivatives used as the starting materials were prepared as follows: (a) A mixture of 200 mg (0.43 mmol) of tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate, 263 mg (1.29 mmol) of tributyl-phosphine and 284 mg (1.29 mmol) of diphenyl sulphide in 1 ml of pyridine was stirred at room temperature for 18 hours. Subse¬quently, the reaction mixture was evaporated under reduced pressure and the residue, without further working-up, was chromatographed directly on silica gel using methylene chloride as the eluent. The tert-butyl (3RS,4RS)-3-naphthalen-2-yl-methoxy-4-[4-(2-phenylsulphanyl-ethyl)-phenyl]-piperidine-1-carboxylate was obtained as a colourless oil in quantitative yield; MS: 554 (M+H)+. (b) A solution of 216 mg (0.23 mmol) of tetrabutylammonium ozone was added dropwise very slowly at room temperature to a solution of 1 28 mg (0.23 mmol) of tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-phenylsulphanyl-ethyl)-phenyl]-piperidine-1-carboxylate in 10 ml of methylene chloride. After 6 hours the reaction solution was evaporated under reduced pressure and the crude product was chromatographed on silica gel using a 2:1 mixture of hexane and ethyl acetate as the eluent in order to separate the sulphone which had already formed. There were obtained 100 mg (76% of theory) of a mixture of tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-[(RS)- and -[(SR)-2-phenylsulphinyl-ethyi]-phenyl]-piperidine-1-carboxylate as a colourless oil which gradually crystallized out; MS: 570 (M+H)+. (c) In an analogous manner to that described under (b), starting from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-phenylsulphanyl-ethyl)-phenyl]-piperidine-l -carboxylate using an excess of tetrabutylammonium oxone there was obtained tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-phenyl-sulphonyl-ethyl)-phenyl]-piperidine-1-carboxylate as a colour¬less foam; MS: 603 (M+NH4)+. (d) In an analogous manner to that described under (a), by reacting tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate with bis-(benzothiazol-2-yl) disulphide there was obtained tert-butyl (3RS,4RS)-4-[4-(2-benzothiazol-2-ylsulphanyl-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a yellowish solid; MS: 611 (M+H)+. (e) In an analogous manner to that described under (a), by reacting tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate with (benzo-thiazol-2-yl) disulphide there was obtained tert-butyl (3RS,4RS)-4-[4-(benzothiazol-2-ylsulphanylmethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a yellowish foam; MS: 597 (M+H)+ (f) In an analogous manner to that described under (a), by reacting tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate with bis-(1-phenyl-lH-tetrazol-5-yl) disulphide there was obtained tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(1 -phenyl-1 H-tetrazol-5-ylsulphanylmethyl)-phenyl]-piperidine-1-carboxylate as a colourless foam; MS: 630 (M+Na)+. (g) In an analogous manner to that described in Example 32(b), from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-l-carboxylate there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenoxy-ethyl)-phenyl]-piperidine-1-carboxylate as a colourless oil; MS: 555 (M+NH4)+. Example 34 (a) To a solution of 100 mg (0.22 mmol) of tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-yl- methoxy)-piperidine-1-carboxylate in 10 ml of tetrahydrofuran were added 68 mg (0.66 mmol) of triethylamine and thereafter dropwise at 0°C 25 mg (0.26 mmol) of methanesulphonyl chloride. The reaction solution was stirred at room temperature for 90 minutes, thereafter 38 mg (0.33 mmol) of 2-mercapto-pyrimidine were added and the mixture was stirred at room temperature for a further 18 hours. For the working-up, the reaction mixture was evaporated under reduced pressure, the residue was taken up in 20 ml of methylene chloride and then extracted with 10 ml of water. The organic phase was dried over sodium sulphate and subsequently evaporated under reduced pressure. For purification, the crude product was chromato-graphed on silica gel using a 5:1 mixture of hexane and ethyl acetate as the eluent. There were obtained 100 mg (82% of theory) of tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(pyrimidin-2-ylsulphanylmethyl)-phenyl]-piperidine-1-carboxy-late as a yellowish oil; MS: 542 (M+H)+. (b) In an analogous manner to that described in Example 22(1), by cleavage of the BOC group there was obtained (3RS,4RS)-2-[4- (3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzylsulphanyl]- pyrimidine as a yellow foam; MS: 442 (M+H)+. Example 35 The following compounds were obtained in an analogous manner to that described in Example 22(1) by cleavage of the BOC group using acid: 1) - (3RS,4RS)-2-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzylsulphanyl]-6-nitro-benzothiazole hydroc hloride as a yellowish foam, MS: 542 (M+H)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(6-nitro-benzothiazol-2-yl-sulphanylmethyl)-phenyl]-piperidine-1-carboxylate; 2) - (3RS,4RS)-3-{4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenyl}-propionitrile trifluoroacetate as a white powder, MS: 371 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-cyano-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate using trifluoroacetic acid in methylene chloride. The BOC derivatives used as the starting materials were obtained as follows: (a) In an analogous manner to that described in Example 34(a), by reacting tert-butyl (3RS,4RS)-4-(4-hydroxymethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate with 6-nitr0-2-mercaptobenzothiazole there was obtained, via the mesylate prepared in situ, tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(6-nitro-benzothiazol-2-ylsulphanylmethyl)-phenyl]-piperidine-1-carboxylate as a yellow solid, MS: 642 (M+H)+. (b) In an analogous manner to that described in Example 34(a), by reacting tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-pheny I ]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate with potassium cyanide in dimethylformamide there was obtained, via the corresponding mesylate, tert-butyl (3RS,4RS)-4-[4-(2-cyano-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a white powder, MS: 471 (M+H)+. Example 36 (a) 6.95 g (44 mmol) of powdered potassium permanganate dissolved in a mixture of 100 ml of water and 100 ml of glacial acetic acid as well as 0.73 g (2 mmol) of tetrabutylammonium iodide were added to a solution of 5.0 g (10.83 mmol) of tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate in 500 ml of benzene. The reaction mixture was stirred intensively for 48 hours. For the working-up, the phases were separated. The organic phase was washed with 100 ml of saturated sodium thiosulphate solution. The aqueous phase was decolorized by the addition of saturated sodium thiosulphate solution and subsequently extracted twice with 100 ml of ethyl acetate and 100 ml of methylene chloride each time. The organic phases were combined, dried over sodium sulphate and evaporated under reduced pressure. For purification, the crude material was chromatographed on silica gel using a 9:1 mixture of methylene chloride and methanol as the eluent after the column had previously been prepared with a 90:10:0.1 mixture of methylene chloride, methanol and ammonia. There were obtained 2.6 g (50% of theory) of (3RS,4RS)-[4-(1-tert-butoxy-carbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-acetic acid as a colourless, amorphous solid; MS: 476 (M+H)+. (b) A solution of 150 mg (0.32 mmol) of (3RS,4RS)-[4-(1-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-acetic acid and 55 mg (0.32 mmol) of 2-amino-1-phenyl-ethanone in 5 ml of dimethylformamide was treated in sequence with 44.6 |il (0.32 mmol) of triethylamine and 96 mg (0.32 mmol) of 0-(1,2-dihydr0-2-oxo-1 -pyridyl)-N,N,N',N'-tetramethyluronium tetrafluoroborate (TPTU) and the mixture was stirred at room temperature for 18 hours. For the working-up, the reaction was evaporated in an oil pump vacuum, the residue was taken up in 20 ml of methylene chloride and washed with 5 ml of water. The organic phase was dried over sodium sulphate and evaporated under reduced pressure. For purification, the crude material was chromatographed on silica gel using a 95:5 mixture of methylene chloride and methanol as the eluent. There were obtained 120 mg (64% of theory) of tert-butyl (3RS,4RS)-3-(naphthalen-2-yl-methoxy)-4-{4-[(2-ox0-2-phenyl-ethylcarbamoyl)-methyl]-phenyl}-piperidine-1-carboxylate as a colourless oil; MS: 615 (M+Na)+ (c) In an analogous manner to that described in Example 22(1), starting from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-{4-[(2-ox0-2-phenyl-ethylcarbamoyl)-methyl]-phenyl}-piperidine-1-carboxylate by cleavage of the BOC group using trifluoroacetic acid in methylene chloride there was obtained (3RS,4RS)-2-{4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenyl}-N-(2-ox0-2-phenyl-ethyl)-acetamide trifluoroacetate as a white powder; MS: 493 (M+H)+. Example 37 The following compounds were obtained in an analogous manner to that described in Example 36(b)-(c): 1) - From (3RS,4RS)-[4-(l-tert-butoxycarbonyl-3-naphthalen- 2-ylmethoxy-piperidin-4-yl)-phenyl]-acetic acid and 3-amino-l- phenyl-propan-1 -one [H.Zinner and G.Brossmann, J. Prakt. Chem. 5, 91 (1958)] there was obtained tert-butyl (3RS,4RS)-3-(naphth- alen-2-ylmethoxy)-4-{4-[(3-oxo-3-phenyl-propylcarbamoyl)- methyl3-phenyl}-piperldine-1-carboxylate, MS: 607 (M+H)+, 1 51 54B66, which, after cleavage of the BOC group, gave (3RS,4RS)-2-[4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenyl]-N-(3-oxo-3-phenyl-propyl)-acetamide trifluoroacetate as a white powder; MS: 507 (M+H)+; 2) - from (3RS,4RS)-[4-(1-tert-butoxycarbonyl-3-naphthalen- 2-ylmethoxy-piperidin-4-yl)-phenyl]-acetic acid and 2-hydroxy- 1-phenyl-ethanone with 1,1-carbonyldiimida2ole as the condensation agent there was obtained tert-butyl (3RS,4RS)-3- (naphthalen-2-ylmethoxy)-4-[4-(2-ox0-2-phenyl-ethoxy- carbonylmethyl)-phenyl]-piperidine-1-carboxylate which, after cleavage of the BOC group, gave 2-ox0-2-phenyl-ethyl (3RS,4RS)- [4-[3-(naphthaien-2-ylmethoxy)-piperidin-4-yl]-phenyl]-acetate trifluoroacetate as a white powder; MS: 494 (M+H)+; 3) - from (3RS,4RS)-[4-(l-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-acetic acid and phenol with 1,1-carbonyldiimidazole as the condensation agent there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-(4-phenoxycarbonylmethyl-phenyi)-piperidine-1 -carboxylate which, after cleavage of the BOC group, gave phenyl (3RS,4RS)-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-acetate trifluoroacetate as white crystals; MS: 452 (M+H)+. Example 38 (a) A solution of 100 mg (0.21 mmol) of (3RS,4RS)-[4-(l-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-acetic acid in 5 ml of dimethylformamide was treated with 50 mg (0.31 mmol) of 1,1-carbonyldiimidazole and the mixture was stirred at 50°C for one hour. Subsequently, the mixture was cooled to room temperature, a solution of 45 mg (0.33 mmol) of benzamidoxime in 2 ml of dimethylformamide was added and the mixture was stirred at 50°C for one hour. For the working-up, the mixture was cooled to room temperature and the dimethylformamide was distilled off in an oil pump vacuum. The residue was chromatographed on silica gel using a 98:2:0.1 mixture of methylene chloride, methanol and ammonia as the eluent. There were obtained 90 mg (72% of theory) of the benzamidoxime ester as a colourless foam; MS: 594 (M+H)+, Rf: 0.68 (SiOz, methylene chloride:methanol:ammonia = 95:5:0.1) (b) A solution of 90 mg (0.15 mmol) of the benzamidoxime ester in 10 ml of dimethylformamide was heated to 130°C for 18 hours. For the working-up, the mixture was evaporated under reduced pressure and the residue was chromatographed on silica gel using a 4:1 mixture of hexane and ethyl acetate as the eluent. There were obtained 63 mg (72% of theory) of tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(3-phenyl-[1,2,4]- oxadiazol-5-ylmethyl)-phenyl]-piperidine-1-carboxylate as a colourless oil; MS: 592 (M+NH4)+. (c) In an analogous manner to that described in Example 22(1), starting from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(3-phenyl-[l,2,4]oxadiazol-5-ylmethyl)-phenyl]-piperidine-1-carboxylate by cleavage of the BOC group using trifluoroacetic acid in methylene chloride there was obtained (3RS,4RS)-3-(3-naphthalen-2-ylmethoxy)-4-[4-(3-phenyl-[1,2,4]oxadJazol-5-ylmethyl)-phenyl]-piperidlne trifluoroacetate as a white powder; MS: 476 (M+H)+. Example 39 (a) A solution of 100 mg (0.21 mmol) of (3RS,4RS)-[4-(1-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-acetic acid in 5 ml of methylene chloride was treated with 1 ml of ethereal diazomethane solution at room temper¬ature and stirred for a further 2 hours. The reaction solution was evaporated under reduced pressure and the tert-butyl (3RS,4RS)-4-(4-methoxycarbonylmethyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate, Rf: 0.5 (hexane:ethyl acetate = 2:1), obtained in quantitative yield, was used in the following step without further purification and characterization. (b) A solution of 102 mg (0.21 mmol) of tert-butyl (3RS,4RS)-4-(4-methoxycarbonylmethyl-phenyl)-3-(naphthalen-2-yl-methoxy)-piperidine-l-carboxylate in 0.5 ml of hydrazine hydrate was heated to 120°C for 18 hours. For the working-up, the reaction mixture was cooled to room temperature, treated with 3 ml of ice-water and extracted twice with 5 ml of methylene chloride each time. The combined organic phases were dried over sodium sulphate and evaporated under reduced pressure. There were obtained 63 mg (63% of theory) of tert-butyl (3RS,4RS)-4-(4-hydrazin°C arbonylmethyl-phenyl)-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate as a colourless foam; Rf: 0.22 (Si02, methylene chloride:methanol:ammonia = 95:5:0.1). (c) A mixture of 60 mg (0.12 mmol) of tert-butyl (3RS,4RS)-4- (4-hydrazin°C arbonylmethyl-phenyl)-3-(naphthalen-2-yl- methoxy)-piperidine-1-carboxylate and 27.7µl (0.12 mmol) of triethyl orthobenzoate in 5 ml of ethanol was boiled under reflux for 18 hours. After cooling the mixture was evaporated under reduced pressure and the residue was chromatographed on silica gel using a 2:1 mixture of hexane and ethyl acetate as the eluent. There were obtained 30 mg (44% of theory) or tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(5-phenyl-[ 1,3,4]-oxadiazol-2-ylmethyl)-phenyl]-piperidine-1-carboxylate as a colourless foam; MS: 575 (M+H)+. (d) In an analogous manner to that described in Example 22(1), starting from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)- 4-[4-(5-phenyl-[1,3,4]oxadiazol-2-ylmethyl)-phenyl]-piperidine- 1 -carboxylate by cleavage of the BOC group using trifluoroacetic acid in methylene chloride there was obtained (3RS,4RS)-3- naphthalen-2-yImethoxy-4-[4-(5-phenyl-[1,3,4]oxadiazol-2- ylmethyl)-phenyl]-piperidine trifluoroacetate as a white powder; MS: 476 (M+H)+. Example 40 (a) 70 mg (0.51 mmol) of phenylmagnesium chloride were added using a syringe to a solution of 80 mg (0.17 mmol) of tert-butyl (3RS,4RS)-4-[4-(2-cyano-ethyl)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate (Example 35) in 10 ml of toluene. The reaction mixture was boiled under reflux for 3 hours, thereafter cooled to room temperature and hydrolyzed with 4 ml of IN hydroc hloric acid. The mixture was subsequently stirred at 80°C for 1 hour, then cooled to room temperature and extracted twice with ethyl acetate. The combined organic phases were dried over sodium sulphate and evaporated under reduced pressure. The residue was chromatographed on silica gel using a 90:10:0.1 mixture of methylene chloride, methanol and ammonia as the eluent. The resulting mixture of (3RS,4RS)-3-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-1-phenyl-propan-1-one and (3RS,4RS)-3-{4-[3-(naphthalen-2-ylmethoxy)- piperidin-4-yl]-phenyl}-propionic acid was converted into the corresponding BOC derivative in an analogous manner to that described in Example 1 (f) and subsequently chromatographed on silica gel using a 2:1 mixture of hexane and ethyl acetate as the eluent. There were obtained 13 mg (14% of theory) of tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(3-oxo-3-phenyl-propyl)-phenyl]-piperidine-1-carboxylate as a colourless foam; Rf : 0.38 (hexane: = 2:1). (b) In an analogous manner to that described in Example 22(1), starting from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(3-oxo-3-phenyl-propyl)-phenyl]-piperidine-1-carboxylate by cleavage of the BOC group using trifluoroacetic acid in methylene chloride there was obtained (3RS,4RS)-3-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenyl]-1-phenyl-propan-1-one trifluoroacetate as a white powder; MS: 450 (M+H)+. Example 41 (a) A solution of 60 mg (0.13 mmol) of tert-butyl (3RS,4RS)-4-(3-methoxycarbonyl-phenyl)-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate [Example 26(e)] and 0.26 ml (0.26 mmol) of IN sodium hydroxide solution in 2 ml of methanol was stirred at 30°C for 18 hours. For the working-up, the reaction mixture was neutralized with IN hydroc hloric acid and extracted twice with 10 ml of methylene chloride each time. The organic phases were combined, dried over sodium sulphate and evaporated under reduced pressure. The residue was crystallized from a mixture of hexane and diethyl ether. There were obtained 45 mg (75% of theory) of (3RS,4RS)-3-(1-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzoic acid as colourless crystals; MS: 462 (M+H)+. (b) In an analogous manner to that described in Example 36(b), by condensing (3RS,4RS)-3-(1-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzoic acid with benzylamine using 1,1-carbonyldiimidazole as the condensation agent there was obtained tert-butyl (3RS,4RS)-4-(3-benzyl- carbamoyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate as a colourless oil; MS: 551 (M+H)+. (c) In an analogous manner to that described in Example 22(1), by cleavage of the BOC group from tert-butyl (3RS,4RS)-4-(3-benzylcarbamoyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate there was obtained (3RS,4RS)-N-benzyl-3-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzamide hydroc hloride as a white powder; MS: 451 (M+H)+. Example 42 The following compounds were obtained in an analogous manner to that described in Example 11 (I) by cleavage of the BOC group using trifluoroacetic acid in methylene chloride: 1) - (3RS,4RS)-N-benzyl-4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-benzamide as a white powder, MS: 453 (M+H)+, from tert-butyl (3RS,4RS)-4-(4-benzylcarbamoyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 2) - (3RS,4RS)-4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-N-(3-oxo-3-phenyl-propyl)-benzamide trifluoroacetate as a white powder, MS: 493 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(3-oxo-3-phenyl-propyl-carbamoyl)-phenyl]-piperidine-l-carboxylate; 3) - (3RS,4RS)-4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-N-(2-ox0-2-phenyl-ethyl)-benzamide trifluoroacetate as a white powder, MS: 479 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-ox0-2-phenyl-ethyl-carbamoyl)-phenyl]-piperidine-l-carboxamide. The BOC derivatives used as the starting materials were obtained as follows: (a) In an analogous manner to that described in Example 41(b), by the alkaline saponification of tert-butyl (3RS,4RS)-4-(4- methoxycarbonyl-phenyi)-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate there was obtained (3RS,4RS)-4-(1-tert-butoxy-carbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzoic acid as a colourless solid; MS: 461 (M)+. (b) In an analogous manner to that described in Example 36(b), by condensing (3RS,4RS)-4-(l-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzoic acid with benzylamine there was obtained tert-butyl (3RS,4RS)-4-(4-benzylcarbamoyl-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless foam; MS: 551 (M+H)+. (c) In an analogous manner to that described in Example 36(b), by condensing (3RS,4RS)-4-(1-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzoic acid with 3-amino-1-phenyl-propan-1-one there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(3-oxo-3-phenyl-propylcarbamoyl)-phenyl]-piperidine-l-carboxylate as a colourless foam; MS: 593 (M+H)+. (d) In an analogous manner to that described in Example 36(b), by condensing (3RS,4RS)-4-(1-tert-butoxycarbonyl-3-naphthalen-2-ylmethoxy-piperidin-4-yl)-benzoic acid with 2-amino-l-phenyl-ethanone there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-ox0-2-phenyl-ethylcarbamoyl)-phenyl]-piperidine-1-carboxylate as a colourless foam; MS: 579 (M+H)+. Example 43 (a) A solution of 1,0 g (3 mmol) of tert-butyl (3RS,4RS)-3-hydroxy-4-(4-methoxycarbonyl-phenyl)-piperidine-1-carboxylate in 100 ml of methanol was treated with 100 mg of rhodium (5%) on aluminium oxide and hydrogenated for 5 hours at 50°C under 10 bar of hydrogen. Thereafter, the reaction mixture was filtered over 30 g of Dicalit, the filter aid was rinsed with 200 ml of methanol and the solution obtained was evaporated under reduced pressure. There was obtained in quantitative yield a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-3-hydroxy-4-(trans- and -(cis-4-methoxycarbonyi-cyclohexyl)-piperidine-4-carboxylate as a colourless solid; MS: 342 (M+H)+. The following procedure was carried out in an analogous manner to that described in Example 22(e) and (h)-(l): (b) From a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-3-hydroxy-4-(trans- and -(cis-4-methoxycarbonyl-cyclohexyl)-piperidin-4-carboxylate by reduction using lithium borohydride there was obtained a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-3-hydroxy-4-(4-hydroxymethyl-cyclohexyl)-piperidine-1-carboxylate as a colourless foam; MS: 314 (M+H)+. (c) From a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-3-hydroxy-4-(4-hydroxymethyl-cyclohexyl)-piperidine-1-carboxylate there was obtained by introduction of the trityl group a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-3-hydroxy-4-(4-trityloxymethyl-cyclohexyl)-piperidine-1-carboxylate as a colourless foam; MS: 573 (M+H)+. (d) Alkylation of a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-3-hydroxy-4-(4-trityloxymethyl-cyclohexyl)-piperidine-1-carboxylate with 2-bromomethylnaphthalene gave a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-3-naphthalen-2-ylmethoxy-4-(4-trityloxymethyl-cyclohexyl)-piperidine-1-carboxylate as a colourless foam: MS: 713 (M+NH4)+. (e) From a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-3-naphthalen-2-ylmethoxy-4-(4-trityloxymethyl-cyclohexyl)-piperidine-1-carboxylate by cleavage of the trityl group using hydrogen chloride in methanol there was obtained a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-3-naphthalen-2-ylmethoxy-4-(4-hydroxymethyI-cyclohexyl)-piperidine-1-carboxylate as a colourless foam; MS: 453 (M+H)+. (f) Acylation of a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-3-naphthalen-2-ylmethoxy-4-(4-hydroxymethyl- cyclohexyl)-plperidine-1-carboxylate with benzoyl chloride yielded a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-4-(4-benzoyloxymethyl-cyclohexyl)-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate as a colourless oil; MS: 558 (M+H)+. (g) From a 2:1 or 1:2 mixture of tert-butyl (3RS,4RS)-cis- and -trans-4-(4-benzoyloxymethyl-cyclohexyl)-3-naphthalen-2-ylmethoxy-piperidine-1-carboxylate by cleavage of the BOC group using hydrogen chloride in methanol there was obtained a 2:1 or 1:2 mixture of (3RS,4RS)-cis- and -trans 4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-cyclohexylmethyl benzoate as a colourless foam; MS: 458 (M+H)+, Example 44 The following procedure was carried out in an analogous manner to that described in Example 22(a)-(c): (a) 1-Benzyl-4-(4-methoxy-phenyl)-piperidin-4-ol was obtained as a colourless solid, MS: 298 (M+H)+, from 1-benzyl-4-piperidone and 4-iodoanisole. (b) 1 -Benzyl-4-(4-methoxy-phenyl)-1,2,3,6-tetrahydro-pyridine was obtained as a beige solid, MS: 280 (M+H)+, from 1-benzyl-4-(4-methoxy-phenyl)-piperidin-4-ol by elimination. (c) Hydroboration of 1-benzyl-4-(4-methoxy-phenyl)-1,2,3,6-tetrahydro-pyridine gave (3RS,4RS)-1-benzyl-4-(4-methoxy-phenyl)-piperidin-3-ol as colourless crystals; MS: 297 (M)+. (d) 49.6 ml (49.6 mmol, 2 eq.) of an approximately 1M boron tribromide solution in methylene chloride was added dropwise at 3-7°C within 10 minutes to a solution of 7.38 g (24.82 mmol) of (3RS,4RS)-1 -benzyl-4-(4-methoxy-phenyl)-plperidin-3-ol in 248 ml of methylene chloride. This suspension was stirred at room temperature for 3 hours. Subsequently, the reaction mixture was poured into 750 ml of an ice/water mixture, brought to pH 8 with 2N sodium hydroxide solution and extracted three times with 500 ml of methylene chloride each time. The organic phases were washed with a small amount of water, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. This yielded 6.42 g of (3RS,4RS)-1-benzyl-4-(4-hydroxy-phenyl)-piperidin-3-ol in the form of a white foam; MS: 283 (M)+. (e) A solution of 3.0 g, (10.6 mmol) of (3RS,4RS)-l-benzyl-4- (4-hydroxy-phenyl)-piperidin-3-ol in 75 ml of ethyl methyl ketone was treated in succession with 10.84 g (42.4 mmol, 4.8 eq) of 2-(2-iodo-ethoxy)-tetrahydro-pyran and 5.25 g (53 mmol, 5 eq) of potassium carbonate. This mixture was stirred at 95°C for 25 hours. Subsequently, it was concentrated to a few millilitres, poured into 200 ml of an ice/water mixture and extracted three times with 300 ml of methylene chloride each time. The combined organic phases were washed once with a small amount of water, dried over magnesium sulphate, evapor¬ated under reduced pressure and dried in a high vacuum. The thus-obtained crude product (11.81 g) was separated on silica gel using a 99:1 mixture of methylene chloride and methanol as the eluent and yielded 3.2 g (73% of theory) of a mixture of (3RS,4RS)-1-benzyl-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidin-3-ol as a colourless oil; Rf. 0.55 (SiOz, methylene chloride:methanol = 9:1). (f) In an analogous manner to that described in Example 22(i), by alkylating a mixture of (3RS,4RS)-l-benzyl-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidin-3-ol with 2-bromomethylnaphthalene there was obtained a mixture of (3RS,4RS)-1-benzyl-3-(naphthalen-2-ylmethoxy)-4-[4-[2-[(RS)-and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidine as a colourless oil; Rf: 0.46 (SiOz, methylene chloride: = 1:1). (g) In an analogous manner to that described Example 25(a), by cleavage of the benzyl group using 2,2,2-trichloroethyl chloroformate and potassium carbonate there was obtained a mixture of 2,2,2-trichloro-ethyl (3RS,4RS)-3-(naphthalen-2- ylmethoxy)-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidine-1-carboxylate as a colourless oil; MS: 653.3, 655 (M+H)+. (h) A solution of 500 mg (0.785 mmol) of a mixture of 2,2,2-trichloro-ethyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidine-1-carboxylate in 10 ml of methanol was treated with 1 ml of water and 1.120 g (5.888 mmol) of β-toluenesulphonic acid monohydrate. This suspension was stirred at room temper¬ature for 1.5 hours, then concentrated to half of the volume under reduced pressure and extracted four times with methylene chloride against water. The organic phases were each washed once with saturated sodium hydrogen carbonate solution and saturated sodium chloride solution, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. The crude product (465 mg) was separated on silica gel using a 9:1 mixture of methylene chloride and methanol as the eluent. This yielded 344 mg (79% of theory) of 2,2,2-tri-chloroethyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless, amorphous powder; MS: 569.3, 571 (M+NH4)+. (i) In an analogous manner to that described in Example 24(m), from 2,2,2-trichloroethyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate and pyridine-2-carbonyl azide there was obtained 2,2,2-trichloro-ethyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-pyridin-2-ylcarbamoyloxy-ethoxy]-phenyl]-piperidine-1-carboxy-late as a colourless oil; MS: 672.2, 674 (M+H)+. Q) In an analogous manner to that described in Example 25(b), by treating 2,2,2-trichloroethyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-pyridin-2-ylcarbamoyloxy-ethoxy]-phenyl]-piperidine-1-carboxylate with zinc in glacial acetic acid there was obtained (3RS,4RS)-2-[4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenoxy]-ethyl pyridine-2-yl-carbamate as a colourless solid; MS: 498 (M+H)+. Example 45 The following compounds were obtained in an analogous manner to that described in Example 25(b): 1) - (3RS,4RS)-2-[4-[3-(Naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenoxy]-ethyl carbamate as a colourless oil, MS: 421 (M+H)+, from 2,2,2-trichloro-ethyl (3RS,4RS)-4-[4-(2-car-bamoyloxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate; 2) - (3RS,4RS)-2-[4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenoxy]-ethyl morpholine-4-carboxylate as a colourless oil, MS: 491 (M+H)+, from 2,2,2-trichloro-ethyl (3RS,4RS)-4-[4-[2-(morpholin-4-ylcarbonyloxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 3) - (3RS,4RS)-4-(4-methoxy-phenyl)-3-(naphthalen-2-yl-methoxy)-piperidine as a colourless oil, MS: 348 (M+H)+, from 2,2,2-trichloro-ethyl (3RS,4RS)-4-(4-methoxy-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 4) - (3RS,4RS)-2-[4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenoxy]-ethanol as a colourless, amorphous solid, MS: 378 (M+H)+, from a mixture of 2,2,2-trichloro-ethyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidine-1 -carboxylate with simultaneous cleavage of the THP group. The derivatives used as the starting materials were obtained as follows: (a) In an analogous manner to that described in Example 24 (m), from 2,2,2-trichloroethyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate and sodium is°C yanate there was obtained 2,2,2-trichloro-ethyl (3RS,4RS)-4-[4-(2-carbamoyloxy-ethoxy)-phenyl]-3-(naphthalen- 2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil; Rf. 0.28 (Si02, methylene chloride:acetone = 1:1). (b) A solution of 250 mg (0.56 mmol) of 2,2,2-trichloroethyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2- yimethoxy)-piperidine-1-carboxylate in 20 ml of toluene was treated in succession with 250 ml (2.8 mmol, 5.0 eq.) of morpholine-4-carbonyl chloride, 375 mg (3.08 mmol, 5.5 eq.) of 4-dimethylaminopyridine and 20 |il (0.075 mmol, 0.13 eq.) of dibutyltin diacetate. This mixture was boiled under reflux for 64 hours. In the course of the reaction a further 125 ml (1.40 mmol, 5.0 eq.) of morpholine-4-carbonyl chloride and 188 mg (1.56 mmol, 2.3 eq.) of 4-dimethylaminopyridine were added and the mixture was boiled under reflux for a further 24 hours. The reaction mixture, cooled to room temperature, was poured into 100 ml of an ice/water mixture, stirred for 5 minutes and extracted three times with methylene chloride. The organic phases were each washed once with water and saturated sodium chloride solution, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. The crude product (546 mg) was separated on silica gel using a 9:1 mixture of hexane and acetone as the eluent. There were obtained 42 mg (14% of theory) of 2,2,2-trichloro-ethyl (3RS,4RS)-4-[4-[2-(morpholin-4-ylcarbonyloxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil; MS: 665.3, 667 (M+H)+. (c) In an analogous manner to that described in Example 12(b), by alkylating (3RS,4RS)-1-benzyl-4-(4-methoxy-phenyl)- piperidin-3-ol [Example 44 (c)] with 2-bromomethylnaphthalene there was obtained (3RS,4RS)-1-ben2yl-4-(4-methoxy-phenyl)- 3-(naphthalen-2-ylmethoxy)-piperidine as a beige coloured solid; MS: 437 (M)+. Subsequent reaction with 2,2,2-trichloroethyl chloroformate gave 2,2,2-trichloro-ethyl (3RS,4RS)-4-(4- methoxy-phenyl)-3-(naphthalen-2-ylmethoxy)-piperidlne-1- carboxylate as a yellowish oil; MS: 539, 541 (M+NH4)+. Example 46 (a) In an analogous manner to that described in Example 2(e), by hydrogenolytic cleavage of the benzyl group from (3RS,4RS)-1-benzyl-4-(4-hydroxy-phenyl)-piperidin-3-ol [Example 44(d)] there was obtained (3RS,4RS)-4-(4-hydroxy-phenyl)-piperidin-3-ol as a colourless solid; MS: 194 (M+H)+. b) In an analogous manner to that described in Example 22(g), from (3RS,4RS)-4-(4-hydroxy-phenyl)-piperidin-3-ol by introduction of the BOC group there was obtained tert-butyl (3RS,4RS)-3-hydroxy-4-(4-hydroxy-phenyl)-piperidine-1-carboxylate as a colourless foam; MS: 237 (M-C4H8)+. (c) A mixture of 4.5 g (15.3 mmol) of tert-butyl (3RS,4RS)-3- hydroxy-4-(4-hydroxy-phenyl)-piperidine-1-carboxylate, 20.8 g (91.8 mmol, 6.0 eq.) of 2-(3-chloropropyl)-2-phenyl- [1,3]dioxolane [J. Med. Chem. 34, 1 2 (1991)], 14.6 g (105.5 mmol, 6.9 eq.) of potassium carbonate and 2.0 g (0.012 mmol, 0.078 eq.) of potassium iodide in 50 ml of methyl ethyl ketone were stirred in a sealed, pressure-tight vessel at a bath temperature of 100°C for 60 hours. The reaction mixture was poured into an ice/water mixture and extracted three times with ethyl acetate. The organic phases were each washed once with water and saturated sodium chloride solution, dried over magnesium sulphate, concentrated under reduced pressure and dried in a high vacuum. The yellow oil (25.72 g) was separated on silica gel using an elution gradient of 4:1 to 1:1 of a mixture of hexane and ethyl acetate as the eluent. This yielded 5.34 g (72% of theory) of white, crystalline tert-butyl (3RS,4RS)-3-hydroxy-4-[4-[3-(2-phenyl-[1,3]dioxolan-2-yl)-propoxy]-phenyl]-piperidine-1 -carboxylate; MS: 484 (M+H)+. (d) In an analogous manner to that described in Example 22(i), by alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-[4-[3-(2-phenyl- [1,3]dioxolan-2-yl)-propoxy]-phenyI]-piperidine-1 -carboxylate with 2-bromomethylnaphthalene there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-[3-(2-phenyl- [1,3]dioxolan-2-yl)-propoxy]-phenyl]-piperidine-1 -carboxylate as white crystals; MS: 624 (M+H)+. (e) A solution of 193 mg (0.31 mmol) of tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-[3-(2-phenyl-[1,3]dioxolan-2-yl)-propoxy]-phenyl]-piperidine-1-carboxylate in 3 ml of tetrahydrofuran and 3 ml of 2N hydroc hloric acid was stirred at room temperature for 12 hours and at 50°C for 24 hours. Subsequently, the reaction mixture was poured into a 1:1 mixture of water and saturated sodium hydrogen carbonate solution and extracted three times with ethyl acetate. The organic phases were each washed once with water and saturated sodium chloride solution, dried over magnesium sulphate, concentrated under reduced pressure and dried in a high vacuum. The colourless oil (165 mg) was separated on silica gel using a 9:1 mixture of methylene chloride and methanol (extr. against 5 vol.% cone. NH4OH). This yielded 127.4 mg of (3RS,4RS)-4-[4-(3-naphthalen-2-ylmethoxy-plperidin-4-yl)-phenoxy]-1 -phenyl-butan-1 -one in the form of a colourless oil; MS: 502 (M+Na)+. Example 47 The following compounds were obtained in an analogous manner to that described in Example 46(d)-(e) and, respectively, 3(c)-(e): 1) - From tert-butyl (3RS,4RS)-3-hydroxy-4-[4-[3-(2-phenyl-[1,33dioxolan-2-yl)-propoxy]-phenyl]-piperidine-1 -carboxylate by alkylation with 5-bromomethyl-benzo[b]thiophene there was obtained tert-butyl (3RS,4RS)-3-(benzo[b]thiophen-5-yl-methoxy)-4-|4-[3-(2-phenyl-[1,3]dioxolan-2-yl)-propoxy]-phenyl}-piperidine-1-carboxylate, MS: 630 (M+H)+, as a light yellow resin. Subsequent cleavage of the BOC and acetal groups yielded (3RS,4RS)-4-[4-[3-(benzo[b]thiophen-5-ylmethoxy)-piperidin-4-yl]-phenoxy]-1-phenyl-butan-1-one as a colourless resin; MS: 486 (M+H)+. 2) - From tert-butyl (3RS,4RS)-3-hydroxy-4-[4-[3-(2-phenyl-[1,3]dioxolan-2-yl)-propoxy]-phenyl]-piperidine-1 -carboxylate by alkylation with 5-(chloromethyl)lndane there was obtained tert-butyl (3RS,4RS)-3-(indan-5-ylmethoxy)-4-{4-[3-(2-phenyl-[1,3]dioxolan-2-yl)-propoxy]-phenyl}-piperidine-1-carboxylate, MS: 614 (M+H)+, as a light yellow resin. Subsequent cleavage of the BOC and acetyl groups yielded (3RS,4RS)-4-[4-[3-indan-5-ylmethoxy)-piperidin-4-yl]-phenoxy]-1-phenyl-butan-1-one as a colourless resin; MS: 470 (M+H)+. 3) - From tert-butyl (3RS,4RS)-3-hydroxy-4-[4-[3-(2-phenyl-[1,3]dioxolan-2-yl)-propoxy]-phenyl]-piperidine-1 -carboxylate by alkylation with 3-chloromethyl-1-(2-trimethylsilanyl-ethoxy-methyl)-naphthalene there was obtained tert-butyl (3RS,4RS)-4-[4-[3-(2-phenyl-[1,3]dioxolan-2-yl)-propoxy]-phenyl]-3-[4-(2-trimethylsilanyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate, MS: 770 (M+H)+, as a colourless resin. Subsequent cleavage of the BOC group and of the two acetal groups yielded (3RS,4RS)-4-[4-[3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenoxy]-1-phenyl-butan-1-one as a colourless resin; Rf: 0.17 (SiOz, methylene chloride:methanol = 9:1, extracted against 5% ammonia). 4) - From tert-butyl (3RS,4RS)-3-hydroxy-4-(4-hydroxy-phenyl)-piperidine-1-carboxylate by alkylation with 1-bromo-4-(2-bromoethyl)-benzene analogously to Example 46(c) there was obtained tert-butyl (3RS,4RS)-4-[4-[2-(4-bromo-phenoxy)-ethoxy]-phenyl]-3-hydroxy-piperidine-1-carboxylate as a colourless resin. Further alkylation with 2-bromomethyl-naphthalene gave tert-butyl (3RS,4RS)-4-[4-[2-(4-bromo-phenoxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, from which by cleavage of the BOC group there was obtained (3RS,4RS)-4-[4-[2-(4-bromo-phenoxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine as a colourless resin; MS: 532, 534M+H)+. 5) - From tert-butyl (3RS,4RS)-3-hydroxy-4-(4-hydroxy-phenyl)-piperidine-1-carboxylate by alkylation with 2-bromo- methyl-5-phenyl-[1,3,4]oxadiazole analogously to Example 44(e) there was obtained tert-butyl (3RS,4RS)-3-hydroxy-4-[4-(5-phenyl-[1,3,4]oxadiazol-2-ylmethoxy)-phenyl]-piperidine-l -carboxylate as a yellowish, amorphous solid. Further alkylation with 2-bromomethylnaphthalene gave tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(5-phenyl-[1,3,4]oxadiazol-2-ylmethoxy)-phenyl]-piperidine-1-carboxylate, from which by cleavage of the BOC group there was obtained (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(5-phenyl-[1,3,4]oxadiazol-2-ylmethoxy)-phenyl]piperidine as a colourless solid; MS: 492 (M+H)+. 6) - From (3RS,4RS)-3-hydroxy-4-(4-hydroxy-phenyl)- piperidine-1-carboxylate by alkylation with β-bromophenethol analogously to Example 46(c) there was obtained tert-butyl (3RS,4RS)-3-hydroxy-4-[4-(2-phenoxy-ethoxy)-phenyl]-piperidine-1-carboxylate; MS: 414 (M+H)+. Further alkylation with 2-bromomethylnaphthalene gave tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenoxy-ethoxy)-phenyl]-piperidine-1-carboxylate, MS: 554 (M+H)+, from which by cleavage of the BOC group there was obtained (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenoxy-ethoxy)-phenyl]-piperidine; MS: 454 (M+H)+. 7) - From tert-butyl (3RS,4RS)-3-hydroxy-4-[4-(2-phenoxy- ethoxy)-phenyl]-piperidine-1-carboxylate by alkylation with 2- chloromethyl-O-SEM there was obtained tert-butyl (3RS,4RS)-4- [4-(2-phenoxy-ethoxy)-phenyl]-3-[4-(2-trimethylsilanyl-ethoxy- methoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate; MS: 700 (M+H)+. Subsequent cleavage of the BOC and acetal groups yielded (3RS,4RS)-3-{4-[4-(2-phenoxy-ethoxy)-phenyl]- piperidin-3-yloxymethyl}-naphthalen-1-ol; MS: 470 (M+H)+. Example 48 A solution of 18.7 mg (0.494 mmol, 6.7 eq.) of sodium borohydride in 0.35 ml of water was added using a syringe to a solution of 44 mg (0.074 mmol) of (3RS,4RS)-4-[4-[3-(4- hydroxy-naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenoxy]-1-phenyl-butan-1-one in 1.5 ml of dioxan. The mixture was stirred at room temperature for 1.5 hours. Subsequently, the reaction solution was treated with the same amount by volume of ice-water and the mixture was brought to pH 1 with 2N hydroc hloric acid. After stirring at room temperature for 5-10 minutes the mixture was adjusted to pH 9 with concentrated ammonia and the aqueous solution was extracted three times with one equivalent by volume of methylene chloride each time. The combined organic phases were dried over magnesium sulphate, concentrated at 45°C under reduced pressure and dried in a high vacuum. The brownish solid (40.1 mg) was separated on silica gel using a 9:1 mixture of methylene chloride and methanol (extr. against 5 vol.% cone. NH3 aq.) as the eluent. This yielded 13 mg (35% of theory) of (3RS,4RS)-3-[4-[4-(4-hydroxy-4-phenyl-butoxy)-phenyl]-piperidin-4-yloxymethyl]-naphthalen-1 -ol (configuration unknown in the butanol part) as a colourless oil; MS: 498 (M+H)+. Example 49 The following cohols were obtained in an analogous manner to that described in Example 48 by reduction of the ketones: 1) - The 2:1 or 1:2 mixture of (RS)- and (SR)-4-[4-[(3RS,4RS)-3-(indan-5-ylmethoxy)-piperidin-4-yl]-phenoxy]-1-phenyl-butan-1-ol as a colourless resin, MS: 472 (M+H)+, from (3RS,4RS)-4-[4-[3-indan-5-ylmethoxy)-piperidin-4-yl]-phenoxy]-1 -phenyl-butan-1 -one; 2) - The mixture of (RS)- and (SR)-4-[4-[(3RS,4RS)-3-(benzo-[b]thiopen-5-ylmethoxy)-piperidin-4-yl]-phenoxy]-1-phenyl-butan-1-ol as a colourless resin, MS: 488 (M+H))+, from (3RS,4RS)-4-[4-[3-(benzo[b]thiophen-5-ylmethoxy)-piperidin-4-yl]-phenoxy]-1 -phenyl-butan-1 -one; 3) - 4-[4-[(3RS,4RS)-3-naphthalen-2-ylmethoxy-piperidin-4-yl]-phenoxy]-1-phenyl-butan-1-ol (configuration unknown in the butanol part) as a colourless resin, MS: 482 (M+H)+, from (3RS,4RS)-4-[4-(3-naphthalen-2-ylmethoxy-piperidin-4-yl)-phenoxy]-! -phenyl-butan-1 -one. Example 50 (a) In an analogous manner to that described in Example 22 (g), from (3RS,4RS)-4-[4-(3-naphthalen-2-ylmethoxy-piperidin-4- yl)-phenoxy]-1-phenyl-butan-1-one by introducing the BOC group there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-yl- methoxy)-4-[4-(4-oxo-4-phenyl-butoxy)-phenyl]-piperidine-l- carboxylate as a colourless solid; MS : 580 (M+H)+. (b) Reduction of tert-butyl (3RS,4RS)-3-(naphthalen-2-yl-methoxy)-4-[4-(4-oxo-4-phenyl-butoxy)-phenyl]-piperidine-1-carboxylate analogously to Example 48 yielded tert-butyl (3RS,4RS)-4-[4-(4-hydroxy-4-phenyl-butoxy)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-1 -carboxylate (configuration unknown in the butoxy part) as a colourless solid; MS: 582 (M+l-l)+. (c) Alkylation of tert-butyl (3RS,4RS)-4-[4-(4-hydroxy-4-phenyl-butoxy)-phenyl]-3-naphthalen-2-ylmethoxy-piperidine-l-carboxylate with methyl iodide analogously to Example 22(i) gave tert-butyl (3RS,4RS)-4-[4-(4-methoxy-4-phenyl-butoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate (configuration unknown in the butoxy part) as a colourless oil; Rf: 0.61 (SiOz, hexane:ethyl acetate = 2:1). (d) In an analogous manner to that described in Example 22(1), from tert-butyl (3RS,4RS)-4-[4-(4-methoxy-4-phenyl-butoxy)- phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate by cleavage of the BOC group there was obtained (3RS,4RS)-4-[4-(4- methoxy-4-phenyl-butoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)- piperidine (configuration unknown in the butoxy part) as a colour¬ less resin; MS: 496 (M+H)+. Example 51 A solution of 30 mg (0.052 mmol) of tert-butyl (3RS,4RS)-4-[4-(4-hydroxy-4-phenyl-butoxy)-phenyl]-3-naphthalen-2- ylmethoxy-piperidine-1-carboxylate (configuration unknown in the butoxy part), 25.5 µl (0.186 mmol, 3.6 eq.) of triethylamine and 1.7 ml of methylene chloride was treated in succession with 21.6 \i\ (0.186 mmol, 3.6 eq.) of benzoyl chloride and 2 mg (0.016 mmol) of 4-dimethylaminopyridine. This reaction solution was stirred at room temperature for 10 hours, then poured into 5 ml of water and extracted three times with 10 ml of ethyl acetate each time. The combined organic phases were dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. The light yellow resin (62 mg) was dissolved in 1 ml of methanol, again concentrated, dried in a high vacuum. Without further purification and characterization the product obtained was reacted with hydrogen chloride in methanol analogously to the procedure described in Example 22(1). The brown-yellow resin (56 mg) was separated on silica gel using a 95:5 mixture of methylene chloride and methanol (extracted against 5 vol.% cone, ammonia) as the eluent. There were obtained 15 mg (50% of theory) of 4-[4-[(3RS,4RS)-3-naphthalen-2-ylmethoxy-piperidin-4-yl]-phenoxy]-1-phenyl-butyl benzoate (configuration unknown in the butoxy part) as a colourless resin; MS: 586 (M+H)+. Example 52 A mixture of 600 mg (0.962 mmol) of tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-{4-[3-(2-phenyl-[1,3]dioxolan-2-yl)-propoxy]-phenyl}-piperidine-1-carboxylate in 3.0 ml of methylene chloride and 433 mg (1.92 mmol, 2.0 eq.) of zinc bromide was stirred at room temperature for 4 hours. The reaction mixture was poured into water and extracted three times with ethyl acetate. The organic phases were washed in each case once with water and with saturated sodium chloride solution, dried over magnesium sulphate, evaporated under reduced pressure and dried in a hiah vacuum. The amorohous. slightly yellow crude product was separated on silica gel using a 95:5:0.1 mixture of methylene chloride, methanol and ammonia. There were obtained 355 mg (71% of theory) of (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-[3-(2-phenyl-[1,3]dioxolan-2-yl)-propoxy]-phenyl]-piperidine as a colourless resin; MS: 524 (M+H)+. Example 53 (a) In an analogous manner to that described in Example 44(e)-(f), by alkylating tert-butyl (3RS,4RS)-3-hydroxy-4-(4-hydroxy-phenyl)-piperidine-1-carboxylate with 2-(2-iodo-ethoxy)-tetrahydro-pyran there was obtained a mixture of tert-butyl (3RS,4RS)-3-hydroxy-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidine-1-carboxylate as a yellow oil; Rf: 0.45 (SiOz, hexane:ethyl acetate = 1:1). b) In an analogous manner to that described in Example 22(i), by alkylating the mixture of tert-butyl (3RS,4RS)-3-hydroxy-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidine-1-carboxylate with 2-bromomethyl-naphthalene there was obtained a mixture of tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidine-1-carboxylate as a colourless solid; MS: 579 (M+H)+. (c) A solution of 1.99 g (3.54 mmol) of a mixture of tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidine-1-carboxylate in 11.3 ml of methanol was treated with 11.3 ml of 2N hydrogen chloride in methanol and the mixture was stirred at room temperature for 5 minutes. The reaction mixture was poured into 200 ml of a mixture of ice and saturated sodium hydrogen carbonate solution and extracted three times with ethyl acetate. The organic phases were washed with saturated sodium chloride solution, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. The yellow resin (1.80 g) was recrystallized from hexane. There were obtained 950 mg (56%) of tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl3-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate as a colourless solid; MS: 478 (M+H)+. d) In an analogous manner to that described in Example 22(k), by acylating tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate with 4-chlorobenzoyl chloride there was obtained tert-butyl (3RS,4RS)-4-[4-[2-(4-chloro-benzoyloxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate as a colourless oil; MS : 616 (M+H)+. (e) In an analogous manner to that described in Example 22(1), from tert-butyl (3RS,4RS)-4-[4-[2-(4-chloro-benzoyloxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate by cleavage of the BOC group there was obtained (3RS,4RS)-2-[4-(3-napthalen-2-ylmethoxy-piperidin-4-yl)-phenoxy]-ethyl 4-chloro-benzoate hydroc hloride as a colourless solid; MS: 516 (M+H)+ Example 54 The following compounds were obtained in an analogous manner to that described in Example 22(1) by cleavage of the BOC group using acid: 1) - (3RS,4RS)-2-[4-[3-(Naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenoxy]-ethyl 4-methoxy-benzoate hydroc hloride as a colourless solid, MS: 512 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-[2-(4-methoxy-benzoyloxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 2) - (3RS,4RS)-2-[4-(3-napthalen-2-ylmethoxy-piperidin-4-yl)-phenoxy3-ethyl 2-chloro-benzoate hydroc hloride as a colourless solid, MS: 516 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-[2-(2-chloro-benzoyloxy)-ethoxy]-phenyl3-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 3) - (3RS,4RS)-2-[4-[3-(naphthalen-2-yloxy)-pipendin-4-yl]-phenoxy]-ethyl benzoate as a colourless, amorphous solid, MS: 340 (M-naphthylmethyl)+, from tert-butyl (3RS,4RS)-4-[4-(2-benzoy(oxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate; 4) - (3RS,4RS)-2-[4-[3-(naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenoxy]-ethyl 2-benzoyloxymethyl-benzoate hydroc hloride as a colourless solid, MS: 616 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-[2-(2-benzoy/oxymethyl-benzoyloxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylm6thoxy)-pipendine-l-carboxylate; 5) - (3RS,4RS}-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenyl-sulphanyl-ethoxy)-phenyl]-piperidine hydroc hloride as a colour¬less solid, MS: 470 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenylsulphanyl-ethoxy)-phenyl]-piperidine-l-carboxylate; 6) - (3RS,4RS}-3-naphtha)en-2-ylmethoxyxy-4-[4-(2-phenyl-sulphonyl-ethoxy)-phenyl]-pipendine as a yellowish foam, MS: 502 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-yl- methoxy)-4-[4-(2-pheny)sulphonyl-ethoxy)-phenyl]-piperidine-l- carboxylate; 7) - (3RS,4RS)-N-[2-[4-[3-(naphthalen-2-yloxy)-piperidin-4-yl]-phenoxy]-ethyl-benzamide as a colourless, amorphous solid, MS: 481 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-benzoyl-amino-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; 8) - {3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-[l,2,4]-triazol-l-yl-ethoxy)-phenyl]-piperidine hydroc hloride as a white powder, MS; 428 (M)+, from tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-[1,2,4]triazol-l -yl-ethoxy)-phenyl]-piperidine-1 -carboxylate; 9) - (3RS,4RS)-4-[4-(2-benzyloxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine, MS: 468 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-benzyloxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate. The BOC derivatives used as the starting materials were prepared as follows: (a) A solution of 150 mg (0.314 mmol) of tert-butyl (3RS,4RS) 4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)- piperidine-1-carboxylate, 3.7 mg (0.031 mmol, 0.1 eq.) of 4-dimethylaminopyridine, 65.9 mg (0.375 mmol, 1.2 eq.) of 4-methoxy-benzoyl chloride and 51.7µl of triethylamine in 10 m of methylene chloride was stirred at room temperature for 1 5 hours. This reaction solution was poured into 50 ml of an ice/water mixture and extracted three times with ethyl acetate. The organic phases were washed once with water and once with saturated sodium chloride solution, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. The crude product (208 mg) was separated on silica gel using a 95:5 mixture of hexane and acetone as the eluent. There were obtained 104 mg (51% of theory) of tert-butyl (3RS,4RS)-4-[4-[2-(4-methoxy-benzoyloxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless oil; MS: 612 (M+H)+. (b) In an analogous manner to that described in Example 22(l by acylating (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3- (naphthalen-2-ylmethoxy)-piperidine-1 -carboxylate with 2-chlorobenzoyl chloride there was obtained tert-butyl (3RS,4RS)-4-[4-[2-(2-chloro-benzoyloxy)-ethoxy]-phenyl]-3- (naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a yellow oil; MS: 616 (M+H)+ c) In an analogous manner to that described in Example 22(k), by acylating tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate with benzoyl chloride there was obtained tert-butyl (3RS,4RS)-4' [4-(2-benzoyloxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)- piperidine-1-carboxylate as a colourless, amorphous solid; Rf: 0.61 (Si02, hexane:acetone = 95:5). (d) In an analogous manner to that described in Example 22(k), by acylating tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate with 2-chlor°C arbonyl-benzyl benzoate there was obtained tert-butyl (3RS,4RS)-4-[4-[2-(2-benzoyloxymethyl-benzoyloxy)-ethoxy]-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless solid; MS: 716 (M+H)+. (e) In an analogous manner to that described in Example 33(a), from tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate and diphenyl sulphide there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenylsulphanyl-ethoxy)-phenyl]-piperidine-1-carboxylate as a colourless solid; MS: 570 (M+H)+. (f) In an analogous manner to that described in Example 33(c), by oxidizing tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenylsulphanyl-ethoxy)-phenyl]-piperidine-1-carboxy¬late there was obtained tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-(2-phenylsulphonyl-ethoxy)-phenyl]-piperidine-1-carboxylate as a colourless foam; MS: 619 (M+NH4)+. (g) A solution of 478 mg (1.00 mmol) of tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate and 93 ml of mesyl chloride in 5 ml of pyridine was stirred at room temperature for 2 hours. Subse¬quently, the reaction solution was poured into 50 ml of an ice/water mixture and extracted three times with methylene chloride. The organic phases were washed twice with water, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. This yielded 569 mg of crude tert-butyl (3RS,4RS)-4-[4-(2-methylsulphonyloxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, which was used in the following step without further purification and characterization. (h) A mixture of 569 mg of crude tert-butyl (3RS,4RS)-4-[4-(2-methylsulphonyloxy-ethoxy)-phenyl]-3-(naphthalen-2-yl-methoxy)-piperidine-1-carboxylate and 650 mg of sodium azide in 20 ml of dimethyl sulphoxide was stirred at 80°C for 3.5 hours. Subsequently, this reaction solution was poured into 50 ml of an ice/water mixture and extracted three times with ethyl acetate. The organic phases were washed with water, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. The yellow oil (670 mg) was separated on silica gel using a 9:1 mixture of hexane and ethyl acetate as the eluent. There were obtained 271 mg (54% of theory over both steps) of tert-butyl (3RS,4RS)-4-[4-(2-azido-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate as a colourless solid; MS: 503 (M+H)+. (i) A mixture of 115.9 mg (0.231 mmol) of tert-butyl (3RS,4RS)-4-[4-(2-azido-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate, 87.4 mg (0.330 mmol, 1.43 eq.) of triphenylphosphine and 6.1 |il (6.1 mg, 0.339 mmol, 1.47 eq.) of deionized water was stirred at room temperature for 4 hours. Subsequently, 3 ml of acetic acid were added and the mixture was stirred at room temperature for 17 hours. This reaction mixture was poured into an ice/water mixture, made basic with saturated sodium hydrogen carbonate solution and extracted three times with ethyl acetate. The organic phases were washed once with water and once with saturated sodium chloride solution, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. This yielded 192.3 mg of crude tert-butyl (3RS,4RS)-4-[4-(2-amino-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate, which was used in the following reaction without further purification; Rf: 0.10 (Si02, methylene chioride:acetone = 95:5 + 0.1% ammonia) j) A solution of 192.4 mg of crude tert-butyl (3RS,4RS)-4-[4-(2-amino-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate in 3 ml of methylene chloride was treated at 0°C with 51.7 ml of triethylamine and 64.9 mg (0.462 mmol, 2.0 eq.) of benzoyl chloride and the mixture was stirred at 0oC for 0.75 hr and at room temperature for 3 hours. The reaction mixture was poured into an ice/water mixture, made basic with saturated sodium hydrogen carbonate solution and extracted three times with ethyl acetate. The organic phases were washed once with water and once with saturated sodium chloride solution, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. The colourless oil was separated on silica gel using a 95:5 mixture of methylene chloride and acetone as the eluent. There were obtained 44.9 mg (33% of theory) of tert-butyl (3RS,4RS)-4-[4-(2-benzoylamino-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-l-carboxylate in the form of a light yellow oil; MS: 581 (M+H)+. (k) A solution of 110 mg (0.2 mmol) of crude tert-butyl (3RS,4RS)-4-[4-(2-methylsulphonyloxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate in 5 ml of dimethylformamide was treated with 70 mg (1.0 mmol) of 1,2,4-triazole sodium salt and the reaction mixture was heated to 100°C for 6 hours. Subsequently, the mixture was cooled to room temperature and the dimethylformamide was distilled off in an oil pump vacuum. The residue was taken up in 10 ml of methyl¬ene chloride, washed with 2 ml of water, the organic phase was dried over sodium sulphate and evaporated under reduced pressure. The residue was chromatographed on silica gel using a 95:5:0.1 mixture of methylene chloride, methanol and ammonia as the eluent. There were obtained 90 mg (85% of theory) of tert-butyl (3RS,4RS)-3-naphthalen-2-ylmethoxy-4-[4-(2-[1,2,4]-triazol-1-yl-ethoxy)-phenyl]-piperidine-1-carboxylate as a colourless oil; MS: 529 (M+H)+. (I) In analogy to the procedure described in Example 3(c), by alkylating tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate with benzyl bromide there was obtained tert-butyl (3RS,4RS)-4-[4-(2-benzyloxy-ethoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidine-1-carboxylate; MS: 568 (M+H)+. Example 55 The following compounds were obtained in an analogous manner to that described in Example 22(1): 1) - (3RS,4RS)-2-{4-[3-(4-Hydroxy-naphthalen-2-ylmethoxy)-piperidin-4-yl]-phenoxy}-ethyl 2-chloromethyl-benzoate as a colourless oil from tert-butyl (3RS,4RS)-4-[4-[2-(2-chloro-methyl-benzoyioxy)-ethoxy]-phenyl]-3-[4-(2-trlmethylsilanyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-l-carboxylate by simultaneous cleavage of the BOC and acetal groups; 2) - (3RS,4RS)-2-[4-[3-[4-(2-methoxy-benzyloxy)-naphthalen-2-yImethoxy]-piperidin-4-yl]-phenoxy]-ethyl benzoate hydroc hloride as a colourless solid, MS: 618 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-benzoyloxy-ethoxy)-phenyl]-3-[4-(2-methoxy-benzyloxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate; 3) - (3RS,4RS)-4-[4-(2-benzyloxy-ethoxy)-phenyl]-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-piperidine, MS: 574 (M+H)+, from tert-butyl (3RS,4RS)-4-[4-(2-benzyloxy-ethoxy)-phenyl]-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate. The BOC derivatives used as the starting materials were prepared as follows: (a) In an analogous manner to that described in Example 44(e), by alkylating a mixture of tert-butyl (3RS,4RS)-3-hydroxy-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yloxy]-ethoxy]-phenyl]-piperidine-1-carboxylate with 3-chloromethyl-l-(2-trimethyl-silanyl-ethoxymethoxy)-naphthalene there was obtained a mixture of tert-butyl (3RS,4RS)-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yl]-ethoxy]-phenyl]-3-[4-(2-trimethyl-silanyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate as a colourless oil; MS: 725 (M+NH4)+. (b) In an analogous manner to that described in Example 53(c), from a mixture of tert-butyl (3RS,4RS)-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yl]-ethoxy]-phenyl]-3-[4-(2-trimethylsilanyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate there was obtained tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-[4-(2-trimethyl-silanyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate as a colourless solid; MS: 624 (M+H)+. (c) In an analogous manner to that described in Example 22(l (d) 200 mg (0.28 mmol) of a mixture of tert-butyl (3RS,4RS)-4-[4-[2-[(RS)- and -[(SR)-tetrahydro-pyran-2-yl]-ethoxy]-phenyl]-3-[4-(2-trimethylsilanyl-ethoxymethoxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate were dissolved in 7.6 ml 0.1M hydrogen chloride in methanol and the mixture was stirred at room temperature for 2 hours. Subsequently, a further 0.36 ml of 2M hydrogen chloride in methanol was added and the mixture was stirred at room temperature for a further 2 hours. This reaction solution was poured into semi-saturated sodium hydrogen carbonate solution and extracted three times with ethyl acetate. The organic phases were washed once with water and once with saturated sodium chloride solution, dried over magnesium sulphate, evaporated under reduced pressure and dried in a high vacuum. The yellowish oil (204 mg) was separated on silica gel using a 1:1 mixture of hexane and ethyl acetate (extracted against concentrated ammonia). This yielded 111 mg (80% of theory) of tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(4-hydroxy-naphthalen-2-ylmethoxy)- piperldlne-1-carboxylate in the form of a colourless oil; Rf: 0.26 (SiOz, hexane:ethyl acetate = 1:1). (e) In an analogous manner to that described in Example 44(e), by alkylating tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(4-hydroxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate with 2-methoxyben2yl chloride there was obtained tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-[4-(2-methoxy-benzyloxy)-naphthalen-2-ylmethoxy]-piperidine-1-carboxylate as a colourless oil; MS: 652 (M+K)+. (f) In an analogous manner to that described in Example 22(k), by acylating tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-[4-(2-methoxy-benzyloxy)-naphthalen-2-ylmethoxy]-plperidine-l-carboxylate with benzoyl chloride there was obtained tert-butyl (3RS,4RS)-4-[4-(2-benzoyloxy-ethoxy)-phenyl]-3-[4-(2-methoxy-benzyloxy)-naphthalen-2-ylmethoxy]-piperidine-l-carboxylate as a colourless oil; MS: 736 (M+H)+. (g) In an analogous manner to that described in Example 1(g), by two-fold alkylation of tert-butyl (3RS,4RS)-4-[4-(2-hydroxy-ethoxy)-phenyl]-3-(4-hydroxy-naphtha!en-2-ylmethoxy)-piperidine-1-carboxylate with benzyl bromide there was obtained tert-butyl (3RS,4RS)-4-[4-(2-benzyloxy-ethoxy)-phenyl]-3-(4-benzy!oxy-naphthalen-2-ylmethoxy)-piperidine-l-carboxylate. Example 56 The following compounds were obtained in an analogous manner to that described in Example 22(1) by simultaneous cleavage of the BOC and SEM groups using acid: 1) - (3RS,4RS)-2-[4-(3-Naphthalen-2-ylmethoxy-piperidin-4-yl)-phenoxy]-ethyl 4-hydroxy-benzoate hydroc hloride as a colourless solid, MS: 498 (M+H)+, from tert-butyl (3RS,4RS)-3-(naphthalen-2-ylmethoxy)-4-[4-[2-[4-(2-trimethylsilanyl-ethoxymethoxy)-benzoyloxy]-ethoxy]-phenyl]-piperidine-1-carboxylate; WE CLAIM : I. Compounds of the general formula wherein R1 represents aryl or heterocyclyl; R2 represents phenyl, naphthyl, acenaphthyl, cyclohexyl, pyridyl, pyrimidinyl, pyrazinyl, oxo-pyridinyl, diazinyl, triazolyl, thienyl, oxazolyl, oxadiazolyl, thiazolyl, pyrrolyl or furyl, which groups can be substituted by 1-3 halogen, hydroxy, cyano, trifluoromethyl, lower-alkyl, halo-lower-alkyl, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyl, cyano-lower-alkyl, carboxy-lower-alkyl, lower-alkanoyloxy-lower-alkyl, lower-alkoxycarbonyloxy-lower-alkyl, lower- alkoxycarbonyl, or lower-alkoxy groups, or by lower-alkylenedioxy, and/or by a group LI-T1- L2-T2.L3-T3.L4-T4.L5-U; II, L2, L3, L4 and L5 independently of one another represent a bond, Cl-8-alkylene, C2-8" alkenylene or C2-8-alkynylene or are absent; T1, T2, T3 and T4 independently of one another represent (a) a bond or are absent or represent one of the groups (b) -CH(OH)- (c) -CH(0R6)- (d) -CH(NR5R6)- (e) -CO- (f) -CR7R8- (g) -O- or -NR6- (h) -S(O)O-2 - (i) -SO2NR6 - (j) -NR6 SO2- (k) -C0NR6 - (1) -NR6 co- Cm) -O-CO- (n) -CO-O- (o) -O-CO-O- (p) -O-CO-NR6- (q) -NR6 -CO-NR6- (r) -NR6 -CO-O- and the bonds emanating from (b), (d), (e) and (g)-(r) join to a C atom of the adjacent group and this C atom is saturated when the bond emanates from a hetero atom, and not more than two groups (b)-(f), three groups (g)-(h) and one group (i)-(p) are present; R3 represents hydrogen, hydroxy, lower-alkoxy or lower-alkenyloxy; and R4 represents hydrogen, lower-alkyl, lower-alkenyl, lower-alkoxy, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyl, benzyl, 0x0 or a group R4a.zl.xl- in which Ra represents (a)H- (b) lower-alkyl- (c) lower-alkenyl- (d) hydroxy-lower-alkyl- (e) polyhydroxy-lower-alkyl- (f) lower-alkyl-O-lower-alkyl- (g) aryl- (h) heterocyclyl- (i) arylalkyl- (j) heterocyclylalkyl- (k) aryloxyalkyl- (1) heterocyclyloxylalkyl- (m) (R5R6).N-(CH2)O-2- (n) (R5R6)-N- (o) lower-alkyl-S(0)o.2- (p) aryl-S(O)0.2" (q) heterocyclyl-S(O)O-2- (r) HO-SO3- or salt thereof (s) H2N"C(NH)-NH- (t) NC-, and the bonds emanating from (n)-(t) join to a C atom of the adjacent group and this C atom is saturated when the bond emanates from a hetero atom; Z represents (a) a bond, is absent or represents one of the groups (b) lower-alkylene- (c) lower-alkenylene- (d)-O-,-N(Rn).,-S(O)O-2-(e) -CO¬CO -O-CO- (g) -O-CO-O- (h)-O-CO-N(R11)-, (i)-N(R11)-CO-O- O)-CO-N(R11)- (k)-N(R11)-CO- (1)-N(R11)-CO-N(R11)- (m) -CH(0R9)-, and the bonds emanating from (d) and (f)-(m) join to a C atom of the adjacent group and this C atom is saturated when the bond emanates from a hetero atom; represents (a) a bond, is absent or represents one of the groups (b) -O- (c)-N(R11K (d) -S(O))0.2- (e) -(CH2)1.3- or R3 and R4 together represent a bond; R5 and R6 represent hydrogen, lower-alkyl, lower-alkenyl, aryl-lower-alkyl or acyl or together with the N atom to which they are attached represent a 5- or 6-membered heterocyclic ring which can contain an additional N atom or an O or S atom or a SO or SO2 group and the additional N atom can be optionally substituted by lower-alkyl; R7 and R8 together with the C atom to which they are attached represent a 3-7 membered ring which can contain one or two O or S atoms or SO or SO2 groups; R9 represents hydrogen, lower-alkyl, acyl or arylalkyl; R10 represents carboxyalkyl, alkoxycarbonylalkyl, alkyl or hydrogen; R11 represents hydrogen or lower-alkyl; U represents hydrogen, lower-alkyl, cycloalkyl, cyano, optionally substituted cycloalkyl, aryl or heterocyclyl; Q represents ethylene or is absent; X represents a bond, oxygen, sulphur or a group -CHOR^-, -O-CO, -CO- or C=NOR10-with the bond emanating from an oxygen or sulphur atom joining to a saturated C atom of group Z or to Ri; W represents oxygen or sulphur; Z represents lower-alkylene, lower-alkenylene, hydroxy-lower-alkylidene, -Alk-O- or -Alk-S-, in which Alk represents lower alkylene; provided that a) Z represents lower-alkenylene, when X represents a bond; n is 1 or, when X represents -O-CO-, 0 or 1; and misOor 1; and pharmaceutically usable salts thereof; with the exception of the compound 4-(4-fluorophenyl)-3-(3,4- methylenedioxybenzyloxy)piperidine and its hydrochloride, and trans-3- (3-chlorophenoxy)-4-(3,4-dimethyl-phenoxy)-piperidine and pharmaceutically usable salts thereof. 2. The compounds as claimed in claim 1, of the general formula wherein R1-R4, Q, W, X, Z, n and m have the significance given in claim 1. 3. The compounds as claimed in claim 1, of general formula I-l wherein R1 represents aryl or heterocyclyl; R2 represents phenyl, cyclohexyl, phenyl or cyclohexyl substituted by halogen, hydroxy, cyano, trifluoromethyl, lower-alkyl, halo-lower-alkyl, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyl, cyano-lower-alkyl, carboxy-lower-alkyl, lower-alkanoyloxy-lower-alkyl, lower- alkoxycarbonyloxy-lower-alkyl, lower-alkoxycarbonyl, lower-alkoxy or lower-alkylenedioxy or by a group LI-TI-L2-T3-L4-T5-L4-T5-L5-U; or naphthyl or acenaphthyl; L1, L2, L3, L4 and L5 independently of one another represent a bond, Cl-8-alkylene, C2-8-alkenylene or C2-8-alkynylene or are absent; T1, T2, T3 and T4 independently of one another represent (a) a bond or are absent or represent one of the groups (b) -CH(OH)- (c) -CH(0R6)- (d) -CH(NR5R6)- (e) -CO- (f) -CR7R8- (g) -O-or-NR6-, (h) -S(O)O-2 - (i) -SO2NR6- 0) -NR6SO2- (k) -C0NR6- (1) -NR6CO-(m) -O-CO-(n) -CO-O-(o) -O-CO-O- (p) -O-CO-NR6-, with the bonds emanating from (b), (d), (e) and (g)-(p) joining to a C atom of the adjacent group and this C atom being saturated when the bond emanates from a hetero atom, and not more than two groups (b)-(f), three groups (g)-(h) and one group (i)-(p) being present; R3 represents hydrogen, hydroxy, lower-alkoxy or lower-alkenyloxy; R4 represents hydrogen, lower-alkyl, lower-alkenyl, lower-alkoxy, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyl or benzyl; R5 and R6 represent hydrogen, lower-alkyl or acyl or together with the N atom to which they are attached represent a 5- or 6-membered heterocyclic ring which can contain an additional N atom or an O or S atom; R7 and R8 together with the C atom to which they are attached represent a 3-7 membered ring which can contain one or two oxygen or sulphur atoms; U represents hydrogen, lower-alkyl, cycloalkyl, cyano, aryl or heterocyclyl; Q represents ethylene or is absent; X represents oxygen, sulphur or a group -CHOR9- or -OCO- and R9 represents hydrogen, lower-alkyl, acyl or arylalkyl; W is absent; or can represent oxygen or sulphur when R3 represents hydrogen; and Z represents lower-alkylene or is absent; and pharmaceutically usable salts thereof; with the exception of the compound 4-(4-fluorophenyl)-3-(3,4- methylenedioxybenzyloxy)piperidine and its hydrochloride and trans-3- (3-chlorophenoxy)-4- (3,4-dimethyl-phenoxy)-piperidine and pharmaceutically usable salts thereof. 4. The compounds as claimed in any one of claims 1-3, in which W is absent. 5. The compounds as claimed in any one of claims 1-4, in which Q is absent. 6. The compounds as claimed in any one of claims 1-5, in which X represents oxygen, sulphur or -CO-. 7. The compounds as claimed in any one of claims 1-6, in which Z represents methylene. 8. The compounds as claimed in any one of claims 1-7, in which R1 represents phenyl and phenyl substituted by lower-alkyl, lower-alkenyl, lower-alkoxy, lower-alkylthio, halogen, hydroxy, hydroxy-lower-alkoxy, lower-alkoxy-lower-alkoxy, lower-alkylsulphinyl, lower-alkylsulphonyl, cyano, trifluoromethyl, trifluoromethoxy, carboxy, cyclobutylmethoxy-lower-alkyl, lower-alkylenedioxy, phenyl, phenoxy, lower-alkoxycarbonylphenyl, hydroxy-lower-alkylphenyl, 2,3-dihydroxypropylaminocarbonylphenyl, benzyloxy, benzoyl, pyridyl-lower-alkoxy-lower-alkyl or nicotinoylamino-lower-alkyl. 9. The compounds as claimed in any one of claims 1-7, in which R1 represents naphthyl, naphthyl substituted by hydroxy, oxo, lower-alkoxy, lower-alkenyloxy, lower-alkoxy-lower-alkoxy, di-lower-alkylamino, 2,3-dihydroxypropoxy, 2,3-dihydroxypropoxy-lower-alkoxy, 2,3-dimethoxypropoxy, lower-alkoxycarbonyl-lower-alkoxy, carbamoyl-lower-alkoxy, methoxy-benzyloxy, hydroxybenzyloxy, phenethyloxy, methylenedioxybenzyloxy, dioxolanyl-lower-alkoxy, cyclopropyl-lower-alkoxy, hydroxy-lower-alkoxy, carbamoyloxy-lower-alkoxy, pyridyl-carbamoyloxy-lower-alkoxy, morpholino-lower-alkoxy, 3-morpholino-2-hydroxypropoxy, N-methylpiperazino-N-lower-alkoxy, benzoyloxy-lower-alkoxy or picolyloxy; tetrahydronaphthyl or methyl-substituted tetrahydronaphthyl, or indanyl. 10. The compounds as claimed in any one of claims 1-7, in which R1 represents pyridyl, benzimidazolyl, di-lower-alkoxypyrimidinyl or 2- and 5-benzo[b]thienyl, 6- and 7-quinolyl, 6-and 7-isoquinolyl, 6- and 7-tetrahydroquinolyl, 6- and 7-tetrahydroisoquinolinyl, 6-quinoxalinyl, 6- and 7-quinazolinyl, as well as 6- and 7-quinolyl, 6- and 7-isoquinolyl, 6- and 7-tetrahydroquinolyl, 6- and 7-tetrahydroisoquinolyl, 6-quinoxalinyl or 6- and 7-quinazolinyl substituted by hydroxy, oxo, lower-alkoxy, lower-alkenyloxy, lower-alkoxy-lower-alkoxy, di-lower-alkylamino, 2,3-dihydroxypropoxy, 2,3-dihydroxypropoxy-lower-alkoxy, 2,3-dimethoxy-propoxy, lower-alkoxycarbonyl-lower-alkoxy, carbamoyl-lower-alkoxy, methoxybenzyloxy, hydroxybenzyloxy, phenethyloxy, methylenedioxybenzyloxy, dioxolanyl-lower-alkoxy, cyclopropyl-lower-alkoxy, hydroxy-lower-alkoxy, carbamoyloxy-lower-alkoxy, pyridyl-carbamoyloxy-lower-alkoxy, morpholino-lower-alkoxy, 3-morpholino-2-hydroxypropoxy, N-methylpiperazino-N-lower-alkoxy, benzoyloxy-lower-alkoxy or picolyloxy. 11. The compounds as claimed in any one of claims 1-10, in which R2 represents phenyl or phenyl substituted by halogen, hydroxy, cyano, trifluoromethyl, lower-alkyl, halo-lower-alkyl, hydroxy-lower-alkyl, lower-alkoxy-lower-alkyl, cyano-lower-alkyl, carboxy-lower-alkyl, lower-alkanoyloxy-lower-alkyl, lower-alkoxycarbonyloxy-lower-alkyl, lower-alkoxycarbonyl, lower-alkoxy or lower-alkylenedioxy. 12. The compounds as claimed in any one of claims 1-10, in which R2 represents phenyl substituted by a group L1-T1-L2-T2.L3-T3.L4-T4.L5-U in which L1 and L2 are absent or are Ci-g-alkylene and L3 is absent and U represents hydrogen, lower-alkyl, cyclo-lower-alkyl, phenyl, phenyl substituted by lower-alkyl, lower-alkoxy, lower-alkylthio, lower-alkylsulphinyl, lower-alkylenedioxy, halogen, benzoyl-lower-alkyl, halo-lower-alkyl, lower-alkanoyloxy or hydroxy; or naphthyl; or pyridyl, thienyl, pyrazinyl, triazolyl, imidazolyl, phenyl-oxadiazolyl, thienyl-oxadiazolyl, furyl-oxadiazolyl, phenyl-oxazolyl, benzthiazolyl, furyl, pyrimidinyl, nitrobenzthiazolyl, phenyltetrazolyl or morpholinyl. 13. The compounds as claimed in any one of claims 1-10, in which R2 represents phenyl or phenyl substituted by 2-benzothiazolyl-thio-lower-alkyl, 2-benzyloxy-3-methoxypropoxy, 2-benzoy loxy-3 -methoxypropoxy, 2,3-dihydroxypropoxy, 2-hydroxy-3-benzylamino-propoxy, 2-hydroxy-3-phenoxypropoxy, 2-hydroxy-3 -pheny lthiopropoxy, 2-methoxy-3-phenoxypropoxy, 2-methoxy-3-benzyloxypropoxy, 2-methyl-3-fluoro-phenylbutyryloxy-lower-alkoxy, 2-lower-alkenyloxy-4-phenylbutyl, 3,4,5-trimethoxyphenyl-oxadiazolyl-lower-alkoxy, 6-nitro-2-benzothiazolyl-thio-lower-alkyl, benzamido-lower-alkoxy, benzamido-lower-alkyl, benzoyl-lower-alkoxy and ketals thereof, benzoyl-lower-alkyl and ketals thereof, benzoyl-lower-alkyl-aminocarbonyl-lower-alkyl, benzoyl-lower-alkoxycarbonyl-lower-alkyl, benzoyl-lower-alkylaminocarbonyl, benzoyloxy, benzoyloxy-lower-alkyl-benzoyloxy-lower-alkoxy, benzoyloxy-lower-alkoxy, benzoyloxy-lower-alkyl, benzthiazolylthio-lower-alkoxy, benzthiazolylthio-lower-alkyl, benzylcarbamoyl-lower-alkoxy, benzyloxy-loweralkylcarbonyloxy-lower-alkyl, benzyloxy-lower-alkoxy, benzylthio-lower-alkoxy, carbamoyloxy-lower-alkoxy, carbamoyloxy-lower-alkyl, carboxy-lower-alkoxy, carboxy-lower-alkyl, cyano, cyano-lower-alkoxy, cyano-lower-alkyl, cyanophenyl-lower-alkoxy, cyclohexylcarbonyloxy-lower-alkyl, cyclopropylcarbonyloxy-lower-alkyl, cyclopropyloxy-benzyloxy-lower-alkoxy, dioxolanyl-lower-alkoxy, furyl-oxadiazolyl-lower-alkoxy, furoyloxy-lower-alkoxy, halo-phenoxy-lower-alkyl, halobenzoyl-lower-alkoxy, halobenzoyloxy-lower-alkyl, halobenzoyloxy-lower-alkoxy, halobenzyloxy-lower-alkoxy. halogen, halogen-lower-alkyl, halophenoxy, halophenyl-oxadiazolyl-lower-alkoxy, hydroxy, hydroxy-benzoyloxy-lower-alkyl, hydroxy-benzyloxy-lower-alkoxy, hydroxy-lower-alkoxy, hydroxy-lower-alkyl, imidazolylcarbonyloxy-lower-alkyl, methoxybenzoyl-lower-alkyl, methoxybenzyloxy-lower-alkoxy, methylenedioxybenzoyl-lower-alkoxy, morpholino-lower-alkoxy, morpholinocarbonyloxy-lower-alkoxy, morpholinocarbonyloxy-lower-alkyl, N-methylaminophenyl-carbonyloxy-lower-alkyl, N-methyl-benzylamino-lower-alkoxy, N-methylpyrrolylcarbonyloxy-lower-alkoxy, N-lower-alkylbenzamido-lower-alkyl, naphthyl-lower-alkoxy, nicotinoyloxy-lower-alkoxy, nicotinoyloxy-lower-alkyl, lower-alkanoylbenzoyloxy-lower-alkyl, lower-alkanoyloxy-lower-alkoxy lower-alkanoyloxy-lower-alkyl, lower-alkenyl-benzyloxy-lower-alkoxy, lower-alkenyloxy, lower-alkenyloxy-benzyloxy-lower-alkoxy. lower-alkoxy, lower-alkoxy-benzoyloxy-lower-alkyl, lower-alkoxy-carbonyl, lower-alkoxy-lower-alkyl, lower-alkoxybenzoylamino-lower-alkyl, lower-alkoxybenzylcarbonyloxy-lower-alkyi, lower-alkoxy-benzyloxy-lower-alkoxy, lower-alkoxy-benzylthio-lower-alkoxy, lower-alkoxycarbonyl, lower-alkoxycarbonyl-lower-alkoxy, lower-alkoxycarbonyl-lower-alkyl, lower-alkoxyphenyl-oxadiazolyl-lower-alkoxy, lower-alkyl, lower-alkylbenzyloxy-lower-alkoxy, lower-alkylenedioxy, lower-alkylenedioxybenzyloxy-lower-alkoxy, lower-alkylsulphonylbenzoyl-lower-alkoxy, lower-alkylthiobenzoyloxy-lower-alkoxy, lower-alkylthio-benzyloxy-Iower-alkoxy, benzoyloxybenzyl-lower-alkoxy, hydroxybenzyl-lower-alkoxy, lower-alkoxybenzyl-lower-alkoxy, lower-alkoxybenzylcarbonyloxy-alkoxy, phenoxy-benzyloxy-lower-alkoxy, phenoxycarbonyl-lower-alkyl, phenoxy-lower-alkenyloxy, phenoxy-lower-alkynyloxy, phenyl-lower-alkanoylamino-lower-alkyl, phenyl-lower-alkenyloxy, phenyl-lower-alkoxy, phenoxy-lower-alkyl, phenyl-lower-alkylaminocarbonyl, phenoxy-lower-alkylcarbonyl-lower-alkoxy, phenyl-lower-alkylaminocarbonyl-lower-alkyl, phenylaminocarbonyloxy-lower-alkoxy, phenylaminocarbonyloxy-lower-alkyl, phenyl-hydroxy-lower-alkyl, phenyl-oxadiazolyl-lower-alkoxy phenyl-oxadiazolyl-lower-alkoxy, phenyl-oxadiazolyl-lower-alkyl, phenyl-oxazolyl-lower-alkoxy, phenyloxy-lower-alkoxy, phenylsulphamoyl-lower-alkyl, phenylsulphinyl-lower-alkyl, phenylsulphonyl-lower-alkoxy, phenylsulphonyl-lower-alkyl, phenyltetrazolyl-thio-lower-alkyl, phenylthio-lower-alkoxy, phenylthio-lower-alkyl, pyrazinylcarbonyloxy-lower-alkyl, pyridylaminocarbonyloxy-lower-alkoxy pyridylaminocarbonyloxy-lower-alkyl, pyridylcarbamoyloxy, pyridyl-lower-alkoxy-lower-alkoxy, pyridyl-lower-alkoxy-lower-alkyl, pyridyl-oxadiazolyl-lower-alkoxy, pyridylthio-lower-alkyl, pyrimidinyloxy-lower-alkoxy, pyrimidinylthio-lower-alkyl, thenoyloxy-lower-alkoxy, thenoyloxy-lower-alkyl, thienyl-oxadiazolyl-lower-alkoxy, triazolyl-lower-alkoxy, trifluoromethylbenzyloxy-lower-alkoxy trifluoromethyl. 14. The compounds as claimed in any one of claims 1-10, in which R2 represents cyclohexyl or benzoyloxycyclohexyl. 15. The compounds as claimed in any one of claims 1-10, in which R2 represents naphthyl, tetrahydronaphthyl or acenaphthyl. 16. The compounds as claimed in any one of claims 1-10, in which R2 represents pyridyl or oxopyridyl or pyridyl or oxopyridyl substituted by 3H-2-thioxo-benzthiazolyl, lower-alkoxyphenyl-lower-alkoxy-lower-alkoxy, phenyl-lower-alkoxy-lower-alkoxy, phenyl-lower-alkyl, phenoxy-lower-alkyl or phenyl-lower-alkoxy-lower-alkyl. 17. The compounds as claimed in any one of claims 1-10, in which R2 represents pyrimidinyl or pyrimidinyl substituted by benzodioxanyl-lower-alkoxy, biphenylyloxy, cyclohexyl-lower-alkoxy, cyclohexyloxy-lower-alkoxy, haiophenyl-lower-alkoxy, halophenyl-oxadiazolyl-lower-alkoxy, indanyl-lower-alkoxy, naphthyl-lower-alkoxy, N-lower-alkyl-phenyl-lower-alkoxy-lower-alkylamino, lower-alkythio, lower-alkoxy, lower-alkoxyphenyl-lower-alkoxy-lower-alkoxy, lower-alkoxyphenyl-lower-alkylamino, lower-alkylpyridyl-lower-alkoxy, phenyl-lower-alkoxy-lower-alkoxy, phenyl-lower-alkoxy-Iower-alkylthio, phenyl- lower-alkoxy-lower-alkylamino, phenyl-lower-alkenoxy, phenoxy-phenyl-lower-alkoxy, phenoxy-phenoxy, phenyl-lower-alkynyloxy, phenyl-lower-alkoxy-lower-alkoxy, phenylthio-lower-alkoxy, phenyl-oxazolyl-lower-alkoxy, phenyl-lower-alkynyloxy, phenyl-lower-alkenyloxy, phenyl-lower-alkylamino or phenyl-pyridyl-lower-alkylamino 18. The compounds as claimed in any one of claims 1-10, in which R2 represents halobenzoyl-lower-alkyl-triazolyl, phenyl-lower-alkoxy-lower-alkyl-triazolyl or phenyl-lower-alkoxy-lower-alkoxy-triazolyl. 19. The compounds as claimed in any one of claims 1-18, in which R4 represents 2-oxo-lower-imidazolidin-1 -yl-lower-alkyl, 4-hydroxy-piperazin-1 -yl-lower-alkoxy, 4-hydroxy-piperazin-1 -yl-lower-alkoxy-lower-alkyl, 4-methyl-piperazin-1 -yl-lower-alkoxy, 4-methyl-piperazin-1 -yl-lower-alkoxy-lower-alkyl, 4-methyl-piperazin-1 -yl-lower-alkyl-carbamoyloxy-lower-alkyl, 1,2,4-triazolyl-lower-alkyl, amino, amino-lower-alkyl, amino-lower-alkyl-amino amino-lower-alkyl-amino-lower-alkyl, amino-lower-alkyl-oxy amino-lower-alkyl-oxy-lower-alkyl, aminocarbonyloxy-lower-alkyl, benzyloxy or benzyloxy substituted by lower-alkyl, lower-alkenyl, lower-alkoxy, trifluoromethoxy, lower-alkylthio, hydroxy or halogen, benzyloxy-lower-alkyl or benzyloxy-lower-alkyl substituted by lower-alkyl, lower-alkenyl, lower-alkoxy or halogen, carbamoyloxy-lower-alkyl, cyano-lower-alkyl, di-lower-alkyl-amino, di-lower-alkyl-amino-lower-alkyl, di-lower-alkyl-amino-lower-alkyl-(N-lower-alkyl)-amino-lower-alkyl, di-lower-alkyl-amino-lower-alkyl-amino di-lower-alkyl-amino-lower-alkyl-amino-lower-alkyl, di-lower-alkyl-amino-lower-alkyl-oxy di-lower-alkyl-amino-lower-alkyl-oxy-lower-alkyl, dihydroxy-lower-alkoxy, dihydroxy-lower-alkoxy-lower-alkyl dihydroxy-lower-alkyl-amino, dihydroxy-lower-alkyl-amino-lower-alkyl guanidinyl-lower-alkoxy-lower-alkyl, guanidinyl-lower-alkyl, hydroxy, hydroxy-lower-alkyl, sulphooxy-lower-alkyl, hydroxy-lower-alkyl-oxy, hydroxy-lower-alkyl-oxy-lower-alkyl, morpholin-4-yl-lower-alkoxy, morpholin-4-yl-lower-alkoxy-lower-alkyl5 morpholin-4-yl-lower-alkyl-carbamoyloxy-lower-alkyl, naphthyl-alkoxy or naphthyl-alkoxy substituted by lower-alkoxy, lower-alkoxy, lower-alkoxy-lower-alkoxy lower-alkoxy-lower-alkoxy-lower-alkyl, lower-alkoxy-lower-alkyl, lower-alkyl, lower-alkylsulphonylamino-lower-alkyl, phenoxy-lower-alkyl or phenoxy-lower-alkyl substiuted by lower-alkyl, lower-alkoxy, phenyl-thio-lower-alkyl or phenyl-thio-lower-alkyl substituted by lower-alkyl, lower-alkoxy, piperazin-4-yl-lower-alkoxy, piperazin-4-yl-lower-alkoxy-lower-alkyl, piperidin-1 -yl-lower-alkyl-carbamoyloxy-lower-alkyl, piperidin-4-yl-lower-alkoxy, piperidin-4-yl-lower-alkoxy-lower-alkyl, pyridyl-lower-alkyl-oxy, pyridyl-lower-alkyl-oxy-alkyl, pyridylthio-lower-alkyl, pyrimidinyloxy-lower-alkyl or pyrimidinyloxy-lower-alkyl substituted by lower-alkoxy, tetrazolyl-lower-alkyl, trifluoromethylsulphonylamino-lower-alkyl or hydrogen. 20. The compounds as claimed in any one of claims 1-19, 4-[2-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]-naphthalen-2- yloxy]-ethyl]-morpholine (R)-3-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]-naphthalen- 2-yloxy]-propane-1,2-diol (S)-3-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]-naphthalen-2-yloxyj-propane-1,2-diol (R)-3-[2-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]- naphthalen-2-yloxy]-ethoxy]-propane-l,2-diol (S)-3-[2-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]- naphthalen-2-yloxy]-ethoxy]-propane-1,2-diol l-[2-[7-[(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl]-naphthalen-2- yloxy]-ethyl]-4-methyl-piperazine l-[(3R,4S-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yl]-2-naphthalen-2-yl-ethanone (3R,4S,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-(l,4-dimethoxy-naphthalen-2-ylmethoxy)- piperidin-5-ol 3R54R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-[7-[(R)-2,3-dihydroxy-propoxymethyl]- naphthalen-2-ylmethoxy]-piperidine (3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-[7-[(S)-2,3-dihydroxy-propoxymethyl]- naphthalen-2-ylmethoxy]-piperidine (3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-[6-[(R)-2,3-dihydroxy-propoxymethyl]- naphthalen-2-ylmethoxy]-piperidine (3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-[6-[(S)-2,3-dihydroxy-propoxymethyl]- naphthalen-2-ylmethoxy]-piperidine 4-[(3R,4S,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidin-5- yloxy]-butan-l-ol 3-[(3R,4S,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidin-5- yloxyj-propan-1 -ol l-{2-[(3R,4R,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-piperidin- 5-yloxy]-ethyl}-4-methyl-piperazine (3R,4R,5R)-4-[2-[4-[4(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3- y Imethoxy ] -ethyl} -morpholine (3R,4S,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-(4-methoxy-benzyloxy)-piperidin-5-ol (3R54s,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3,5-bis-(4-methoxy-benzyloxy)-piperidine (3S,4R,5R)-4-[2-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin- 3-ylmethoxy]-ethyl]-morpholine (3S,4R,5R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-methoxymethyl-5-(naphthalen-2- ylmethoxy)-piperidine (3S,4R,5R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3- ylmethyl [3-(4-methyl-piperazin-1 -yl)-propyl]-carbamate (3S,4R,5R)-4-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3- ylmethylsulphanylj-pyridine 2-(4-cyclohexyl-butoxy)-5-[(3R,4R)-3-(l,4-dimethoxy-naphthalen-2-ylmethoxy)-piperidin-4- yl]-pyrimidine (3'R,4'R)-6-(3-cyclohexyl-propoxy)-3'-(1,l,4-dimethoxy-naphthalen-2-ylmethoxy)--1',2',3',4',5',6' hexahydro-[3,4']bipyridine (3S,4R,5R)-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3-yl]- methanol (3S54R,5R)-N-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidm-3- ylmethyl]-N,N',N'-trimethyl-ethane-l,2-diamine (3S,4R,5R)-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3- ylmethyl]-diethyl-amine l-[(3R,4S,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(2-morpholin-4-yl-ethoxymethyl)- piperidin-3-yl]-2-naphthalen-2-yl-ethanone (3R,4R)-3-(l,4-dimethoxy-naphthalen-2-ylme1hoxy)-4-[4-[3-(2-rnethoxy-phenoxy)-propoxy]- phenyl]-piperidine (3R,4s,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3,5-bis-(3,455-trimethoxy-benzyloxy)- piperidine (3R,4R,5S)-4-[4-(3-benzyloxy-propoxy)-phenyl]-3-(naphthalen-2-ylmethoxy)-5-[l,2,4]tt^ 1 -y Imethy 1-piperidine (3R,4R)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]-phenyl]-3-(quinolin-7-ylmethoxy)-piperidine 2-(7-{(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl}-naphthalen-2- ylmethoxy)-ethanol 7-{(3R,4R)-4-[4-(3-benzyloxy-propoxy)-phenyl]-piperidin-3-yloxymethyl}-naphthalen-2- ylmethyl)-dimethyl-amine (3R,4R)-3-(4-benzyloxy-naphthalen-2-ylmethoxy)-4-(4-fluoro-phenyl)-piperidine (3'R,4'R)-3'-(l,4-dimethoxy-naphthalen-2-ylmethoxy)-6-[3-(2-methoxybenzyloxy)-propoxy]- l\2',3',4',5\6'-hexahydro-[3,4]bipyridine (3R,4R)-3-(l,4-dimethoxy-naphthalen-2-ylmethoxy)-4-[4-[3-(2-niethoxy-benzyloxy)-propoxy]- phenyl]-piperidine (3S,4R,5R)-l-[4-[4-(3-benzyloxy-propoxy)-phenyl]-5-(naphthalen-2-ylmethoxy)-piperidin-3- ylniethyl]-imidazolidin-2-one (3R,4R)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]-phenyl]-3-(2-oxo-l,2-dihydro-quinolin-7- ylmethoxy)-piperidine, (3R,4R)-3-(isoqumolin-7-ylmethoxy)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]-phenyl]- piperidine, (3R,4R)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]-phenyl]-3-(l,253,4-tetrahydro-quinoIin-7- ylmethoxy)-piperidine, l-[2-[7-[(3R,4R)-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]-piperidin-3-yloxymethyl]- naphthalin-2-yloxy]-ethyl]-4-methyl-piperazine, l-[2-[7-[(3R,4S,5S)-5-hydroxy-4-[4-[-3-(2-methoxy-benzyloxy)-propoxy]-piperidin-3- yloxymethyl]-naphthalin-2-yloxy]-ethyl]-4-methyl-piperazine, (3R,4S,5S)-3-(l,4-dimethoxy-naphthalin-2-ylmethoxy)-4-[4-[3-(2-methoxy-benzyloxy)- propoxy]-phenyl]-piperidin-5-ol, (3R,4R,5S)-3-(l,4-dimethoxy-naphthalin-2-ylmethoxy)-4-{4-[3-(2-methoxy-benzyioxy)- propoxy]-phenyl}-5-(lH-tetrazol-5-ylmethyl)-piperidineand (3', RS,4'RS)-3--(1.4-dimethoxy-naphthalen-2-ylmethoxy)-443-(2-methoxy-benzyloxy)- propoxy]-r,2;,3',4[',5'6'-hexahydro-[l,4]bipyridin-2-one. 21. A compounds of formula II in which pl represents a protecting group and the remaining symbols have the significance given in claim 1 and hydroxy groups which may be contained in R1, R2 and R4 are present in protected form. 22. A medicament, containing a compound in accordance with any one of claims 1-20 and a therapeutically inert excipient. 23. A process for the manufacture of a compound in accordance with any one of claims 1-20, which process comprises cleaving off the protecting group(s) from a compound of formula II in which pl represents a protecting group and the remaining symbols have the significance given in claim 1 and hydroxy groups which may be contained in R1, R2 and R4 are present in protected form, Optionally, functionally modifying reactive groups in the thus-obtained compound of formula I and/or converting the compound of formula I into a pharmaceutically usable salt, with the manufacture of 4-(4-fluorophenyl)-3-(3,4-methylenedioxy-benzyloxy)piperidine and its hydrochloride and trans-3- (3-chlorophenoxy)-4-(3,4-dimethyl-phenoxy)-piperidine and pharmaceutically usable salts thereof. 24. The compounds as claimed in any one of claims 1-20 for use as therapeutically active substances. Dated this 13 day of August 1996

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1426-mas-1996 others.pdf

1426-mas-1996 petition.pdf

1426-mas-1996-abstract.pdf

1426-mas-1996-claims filed.pdf

1426-mas-1996-claims granted.pdf

1426-mas-1996-correspondnece-others.pdf

1426-mas-1996-correspondnece-po.pdf

1426-mas-1996-description complete filed 1.pdf

1426-mas-1996-description complete filed 2.pdf

1426-mas-1996-description complete filed 3.pdf

1426-mas-1996-form 1.pdf

1426-mas-1996-form 13.pdf

1426-mas-1996-form 18.pdf

1426-mas-1996-form 26.pdf

1426-mas-1996-form 3.pdf

1426-mas-1996-form 4.pdf

1426-mas-1996-form 5.pdf

1426-mas-1996-other documents.pdf