Title of Invention

PROCESS FOR PREPARING 10, 11-METHANOBENZOSUBERANE DERIVATIVES

Abstract This invention provides a process to prepare 10,11-(optionally substituted)methanodibenzosuberane derivatives. The invention also provides an intermediate in this process.
Full Text Treatment of drug and multidrug resistance
typically involves the coadministration of a drug
suitable for treatment of the disease and a compound
which acts through various mechanisms to cause the drug
suitable for treatment of a disease to begin and/or
continue to function as a therapeutic agent.
U.S. patent 5,654,304 ('304), incorporated by
reference herein, discloses a series of 10,11-(optionally
substituted)methanodibenzosuberane derivatives useful in
enhancing the efficacy of existing cancer
chemotherapeutics and for treating nultidrug resistance.
(2R)-anti-5-{3-[4-(10,11-Difluoramethanodibenzosuber-5-
yl)piperazin-1-yl]-2-hydroxypropoxy} quinoline
trihydrochloride is disclosed in '304 and is currently
under development as a pharmaceutical agent.
A crystalline form of this compound, which can
be conveniently formulated for administration to
patients, is highly desirable. Thus, there is a need to
prepare (2R)-anti-5-{3-[4-(10,11-
dif luoromethanodibenzosuber-5-yl) piperazin-1-yl]-2-
hydroxypropoxy}quinoline trihydrochloride as a pure,
highly crystalline solid in order to fulfill exacting
pharmaceutical requirements and specifications.
Preferably, such a crystalline compound will be
readily formed and have favorable bulk or pharmaceutical
characteristics. Examples of favorable bulk
characteristic are drying times, filterability,
solubility, intrinsic dissolution, thermal stability, and
hygroscopicity. Examples of favorable pharmaceutical
characteristics are purity and potency. Decreased
organic solvents in the crystalline structure is
favorable, due in part to potential solvent toxicity to
the recipient as a function of the solvent. Furthermore,
the process for preparing crystalline compounds also
needs to be conveniently carried out on commercial scale.
Although the 10,11-methanedibenzosuberanes
prepared by the procedures taught in '304 could be used
as a pharmaceutical, "one cannot predict which compounds
will be polymorphic" (Florence and Attwood,
Physicochemical Principles of Pharmacy, 2nd Ed., Chapman
and Hall, New York, N.Y., 1988, pages 23-24), it would be
highly desired and advantageous to find a more
crystalline form of (2R)-anti-5-{3-[4-(10,11-
difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-
hydroxypropoxy}quinoline trihydrochloride having the
advantageous properties described above. The preparation
of the new crystalline form of the present invention
fulfills these desirable features.
Additionally, there is need for an improved
process for the preparation 10,11-(optionally
substituted)methariodibenzosuberan6 derivatives which is
more efficient and adaptable to large scale processing
than those previously employed, for example in '304.
Advantages of an improved process may include, for
example, improved stereoselectivity, purity, and yield.
The present invention provides a process for
preparing a compound of formula (1)

wherein A is -CH2-CH2-, -CH2-CHRa-CH2-, -CH2-CHRa-CH2-CH2-,
and Ra is OH;
R1 is H, P, Cl, or Br;
R2 is H, F, Cl, or Br; and
R3 is heteroaryl or phenyl, each optionally substituted
with F, Cl, Br, CF3, CN, NO2, or OCHF2;
or the pharmaceutically acceptable salts thereof,
comprising the steps of:
(a) reacting a compound of formula (4)

with a nucleophile source to form a compound of formula
(5)

wherein X is a leaving group;
(b) reacting a compound of formula (5) with
pyrazine to provide a compound of formula (6)

(c) reducing the compound of formula (6) to
provide a compound of formula (8):

(d) reacting a compound of formula (8) with
either:
(i) an epoxy compound of formula (9)

wherein R3 is as defined above, and n
is an integer 1 or 2; or
(ii) a halo compound of formula (10)
wherein R3 is as defined above, X1 is
halo, and m is 2, 3 or 4; and
(e) optionally forming a pharmaceutically
acceptable salt from the compound produced in step (d) .
The present invention also provides an improved
process for preparing a compound of formula (4) :

comprising reacting dibanzosuberenone with an alkali
trihaloacetate to produce an intermediate 10,11-
(optionally substituted)methanodibenzosuberone and
reducing said intermediate, wherein both reactions are
performed in one operational step.
The ability to perform both reactions in one
operational step is an advantage over the prior art. U.S.
patent 5,654,304 teaches a step-wise preparation of the
10,11- (optionally substituted) methanodibenzosuberol,
beginning with preparation and isolation of 10,11-
(optionally substituted)methanodibenzosuberone from
dibenzosuberenone (2) in diglyme and sodium
trihaloacetate (e.g., sodium chlorodifluoroacetate) in
diglyme at a temperature of 160°C to 165°C followed by
reduction of the intermediate 10,11-(optionally
substituted) methanodibenzosuberone (3) to afford the
corresponding 10,11-(optionally substituted)methano
dibenzosuberol.
Additionally, the present invention
contemplates a compound of formula (6)

wherein R1 and R2 are independently H, F, Cl or Br and X
is leaving group selected from the group consisting of
Br, Cl, OMs, and OTs.
Moreover, the present invention provides a
novel hydrate crystal form of (2R)-anti-5-{3-[4-(10,11-
difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-
hydroxypropoxy}quinoline trihydrochloride ("Hydrate I"),
having an X-ray diffraction pattern which comprises the
following peaks corresponding to d spacings: 7.95 +/-
0.04 A when obtained at 22 ±2°C and 31 ±10% relative
humidity from a copper radiation source.
The present invention also provides the novel
hydrate a characterized above, having an X-ray
diffraction pattern further comprising the following
peaks: 9.93, 4.45, and 3.36 +/- 0.04 A when obtained at
22 ±2°C and 31 ±10% relative humidity fron a copper
radiation source.
The present invention further provides a method
of treatment for a drug resistant disease comprising
coadministaring to a mammal in need thereof a resistance
modulating amount of Hydrate I and an effective amount of
a treatment drug for said drug resistant disease.
The present invention further provides a method
of treatment for a multidrug resistant disease comprising
coadminlstering to a manmal in need thereof a multidrug
resistance modulating amount of Hydrate I and an
effective amount of a treatment drug for said multidrug
resistant disease.
The present invention further provides a method
for enhancing bioavailability of a drug to the brain,
comprising coadministering to a mammal in need thereof a
therapeutically effective amount of said drug and Hydrate
I sufficient enough to allow said drug to cross the
blood-brain barrier and enter the brain.
The present invention further provides a method
for enhancing oral bioavai lability of a drug comprising
administering to a mammal in need thereof a
therapeutically effective amount of said drug and Hydrate
I sufficient enough to allow said drug to be transported
across the gastrointestinal tract and enter the
bloodstream.
The present invention further provides a
solvate of (2R)-anti-5-{3-[4-(10,11-
difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-
hydroxypropoxy}quinoline trihydrochloride.
BRIEF DESCRIPTION OF THE FIGURES
Figure 1 is a representative solid state NMR spectrum
of Hydrate I.
Figure 2 depicts a representative XRD pattern of
Hydrate I.
Figure 3 depicts the XRD pattern, showing systematic
shifts in peak positions as a function of the variable
water content in the lattice of Hydrate I.
Figures 4 representative solid state NMR spectra for
representative solvates.
Figure 5 is depicts representative XRD patterns for
representative solvates.
DETAILED DESCRIPTION OF THE INVENTION
Definitions and General Parameters
The following definitions are set forth to
illustrate and define the meaning and scope of the
various terms used to describe the invention herein.
In general, the term "pharmaceutical" when used
as an adjective means substantially non-toxic to living
organisms. Por example, the term "pharmaceutical salt"
as used herein, refers to salts of the compounds of
formula I which are substantially non-toxic to living
organisms. See, e.g.. Berge, S.M, Bighley, L.D., and
Monkhouse, D.C., "Pharmaceutical Salts", J. Pharm. Sci.,
66:1, 1977. Typical pharmaceutical salts include those
salts prepared by reaction of the compounds of formula I
with an inorganic or organic acid or base. Such salts
are known as acid addition or base addition salts
respectively. These pharmaceutical salts frequently have
enhanced solubility characteristics compared to the
compound from which they are derived, and thus are often
more amenable to formulation as liquids or emulsions.
The term "cancer therapeutic agent" refers to
compounds, which have an anticancer therapeutic effect.
Such compounds are non-antimetabolites such as
anthracycline group antibiotics, e.g. adriamycin,
daunomycin, doxorubicin, or acrasinomycin A; actinomycin
group antibiotics, e.g. actimomycin C or D; chromomycin
group antibiotics, e.g. mithramycin or toyomycin;
vincoalkaloids, e.g. vincristine, or vinblastine;
meitansins; podophyllotoxin derivatives, e.g. VP16-213;
homoharintonin; angwindin; bruceantin; neocarcinostatin;
anthromycin; mitomycin C; and cisplatin. Additional
cancer therapeutic agents may be found in the medical
literature, for example, Section XIII, "Chemotherapy of
Neoplastic Diseases" in Goodman and Oilman's The
Pharmacological Basis of Therapeutics, Seventh Edition,
pages 1240-1306 (1985).
The term "bioavailability" refers to the
degree and rate at which a drug, or other substance,
becomes available to a target tissue within a mammal.
The term "coadministoring" means a disease
treatment drug and Hydrate I are given to a mammal.
The drug and Hydrate I are given to a mammal
simultaneously or at different times.
The term "drug resistance" refers to the
circumstance when a disease does not respond to a
treatment drug or drugs. Drug resistance can be either
intrinsic, which means the disease has never been
responsive to the drug or drugs, or it can be acquired,
which means the disease ceases responding to a drug or
drugs that the disease had previously responded to.
"Multidrug resistance" means a specific type
of drug resistance characterized by cross-resistance of
a disease to more than one functionally and/or
structurally unrelated drugs. Multidrug resistance can
be either intrinsic or acquired.
The term "acid addition salt" refers to a salt
of a compound of formula I prepared by reaction of a
compound of formula I with a mineral or organic acid.
For exemplification of pharmaceutical acid addition salts
see, e.g., Berge, S.M, Bighley, L.D., and Monkhouse,
D.C., J. Pharm. Sci., 66:1, 1977. Since compounds of
this invention can be basic in nature, they accordingly
react with any of a number of inorganic and organic acids
to form pharmaceutical acid addition salts.
Acids commonly employed, to form acid addition
salts are inorganic acids such as hydrochloric acid,
hydrobromic acid; hydroiodic acid, sulfuric acid, phosphoric
acid, and the like, and organic acids, such as
p-toluenesulfonic acid, methanesulfonic acid, oxalic acid,
p-bromophenylsulfonic acid, carbonic acid, suecinic acid,
citric acid, benzoic acid, acetic acid, mono-, di- and
tricarboxylic acids and the like. Examples of such
pharmaceutically acceptable salts are the sulfate,
pyrosulfate, bisulfate, sulfite, bisulfite, phosphate,
monohydrogenphosphate, dihydrogenphosphate, metaphosphate,
pyrophosphate, chloride, bromide, iodide, acetate,
propionate, decanoate, caprylate, acrylate, formate,
isobutyrate, caproate, heptanoate, propiolate, oxalate,
malonate, succinate, suberate, sebacate, fumarate, maleate,
butyne-1,4-dioate, hexyne-1,6-dioate, benzoate,
chlorobenzoate, methylbenzoate, dinitrobenzoate,
hydroxybenzoate, methoxybenzoate, phthalate, sulfonate,
xylenesulfonate, phenylacetate, phenylpropionate.
phenylbutyrate, citrate, lactate, P-hydroxybutyrate,
glycolate, tartrate, methanesulfonate, propanesulfonate,
naphthalene-1-sulfonate, naphthalene-2-sulfonate, mandelate
and the like.
In the general formulae of the present
document, the general chemical terras have their usual
meanings. For example, the term "halo" refers to
halogen, for example, fluoro, bromo, chloro and iodo.
The term "alkyl" refers to a fully saturated
monovalent radical containing only carbon and hydrogen,
and which may be a cyclic, branched or straight "chain
radical. This term is further exemplified by radicals
such as methyl, ethyl, t-butyl, pentyl, pivalyl, heptyl
and adamantyl.
The term "lower alkyl" refers to branched or
straight chain monovalent alkyl radical of one to six
carbon atoms, and optionally to a cyclic monovalent alkyl
radical of three to six carbon atoms. This term is
further exemplified by such radicals as methyl, ethyl, n-
propyl, isopropyl, n-butyl, t-butyl, i-butyl (or 2-
methylpropyl), eyelopropyl -methyl, i-amyl, n-amyl, and
hexyl.
The term "alkylene" refers to a fully saturated
divalent radical containing only carbon and hydrogen, and
which may be a branched or straight chain radical. This
term is further exemplified by radicals such as
methylene, ethylene, n-propylene, t-butylene,
i-pentylene, and n-heptylene.
The term "lower alkylene" refers to a divalent
alkyl radical of one to six carbon atoms. This term is
further exemplified by such radicals as methylene,
ethylene, n-propylene, i-propylene, n-butylene,
t-butylene, i-butyl ene (or 2-methylpropylene),
isoamylene, pentylene, and n-hexylene.
The term "aryl" refers to a phenyl or naphthyl
group which may be optionally substituted with 1-3
substituents independently selected from the group
consisting of fluoro, chloro, bromo, trifluoromethyl,
cyano, nitro and difluoromethoxy.
The term "heteroaryl" refers to a monovalent
aromatic carbocyclic radical having at least one hetero
atom, such as N, O, or S. within the ring, such as
quinolinyl, benzofuranyl, pyridyl, pyrazinyl, carbazolyl,
norhartnanyl, harmanyl, indazolyl, 5-nitroindazolyl,
benzimjdazolyl, benzotriazolyl, anthranilyl, lutidinyl,
collidinyl, acridinyl and isoguinolinyl. The heteroaryl
group may optionally be substituted with 1-3 substituents
independently selected from the group consisting of
fluoro, chloro, bromo, trifluoromethyl, cyano, nitro and
difluoromethoxy.
"Optional" or "optionally" means that the
subsequently described event or circumstance may or may
not occur, and that the description includes instances
where said event or circumstance occurs and instances in
which it does not.
The term "leaving group" as used herein refers
to a group cleavable from the substrate molecule during a
reaction step and comprises a halo group, sulfonates
(e.g., mesylate (OMs) or tosylate (OTs)) and the like
known in the art as leaving groups.
The term "nucleophile source" as used herein
describes a group capable of effecting a nucleophilic
substitution on an alcohol. Such groups include
halogenic acids such as HC1, HBr or HI and sulfonic
acids, sulfonic anhydrides or sulfonic acid halides e.g.,
methanesulfonic acid chloride.
The term "hydrate" as used herein describes the
crystalline lattice which can contain variable amounts of
water depending upon the relative humidity in the storage
conditions. Preferably, Hydrate I contains from about 9%
to about 13% water and less than about 1% organic
solvents.
As used herein the terms "5H-
dibenzo[a,d]cyclohepten-5-one," and "dibenzosuberenone"
are synonymous.
The terms and abbreviations used herein have
their normal meanings unless otherwise designated, for
example, "°C" refers to degrees Celsius; "N" refers to
normal or normality; "mmol" refers to millimole or
millimoles; "g" refers to gram or grams; "d" refers to
density, "min." refers to minutes, "nL" means milliliter
or milliliters; "M" refers to molar or molarity; "HPLC"
refers to high performance liquid chromatography; "mm"
refers to millimeters; "cm" refers to centimeters; "nm"
refers to nanometers; and "tr" refers to retention time.
The present invention provides a process for
preparing a compound of formula (1).

wherein A is -CH2-CH2-, -CH2-CHRa-CH2-, -CH2-CHRa--CH2-CH2-,
and Ra is OH;
R1 is H, F, Cl, or Br;
R2 is H, F, Cl, or Br; and
R3 is heteroaryl or phenyl, each optionally substituted
with F, Cl, Br, CF3, CN, NO2, or OCHF2;
or the pharmaceutically acceptable salts thereof,
comprising the steps of:
(a) reacting a compound of formula (4)

with a nucleophile source to form a compound of formula
(5)

wherein X is a leaving group;
(b) reacting a compound of formula (5) with
pyrazine to provide a compound of formula (6)

(c) reducing the compound of formula (6) to
provide a compound of formula (8) :

(d) reacting a compound of formula (8) with
either:
(i) an epoxy compound of formula (9)

wherein R3 is as defined above, and n
is an integer 1 or 2; or
(ii) a halo compound of formula (10)

wherein R3 is as defined above, X1 is
halo, and in is 2, 3 or 4; and
(e) optionally forming a pharmaceutically
acceptable salt from the compound produced in step (d).
In a preferred aspect the present invention is
a procedure as shown in scheme 1, to afford 10,11-
(optionally substituted) methanodibenzosuberol in a
single operational step from dibenzosuberenone.

This embodiment of the present invention
provides the advantage of efficiency, ease of processing,
reduced cost of manufacture and a more environment-
friendly process over the teaching of U.S. patent
5,654,304. These advantages are made possible by the use
of, and increased solubility of lithium trihaloacetate
salt. The higher reaction concentration incident to
increased solubility of the lithium salt and reduction in
solvent volumes compared to prior art provide increased
throughput and reaction rate. These advantages are also
made possible by the higher reaction temperature made
possible by the use of triglyme, which also enhances the
rate of reaction. Por specific reaction conditions see
steps (a) and (b) of scheme 4.
Preferably 1-(aryloxy or heteroarylaxy)-2,3-
epoxypropane, 1-(aryloxy or heteroaryloxy)-3,4-
epoxybutane, or aryloxy- or heteroaryloxyalkyl halide,
and a 1-[10,11-(optionally substituted)methano-
dibenzosuber-5-yi] piperazine are combined to give the
corresponding 10,11-methanodibenzosurberane derivative of
Formula (1).
A further embodiment of this invention provides
a process for preparing the anti isomer of the novel
10,11-(optionally substituted)methanodibenzosuberyl
pyrazinium salt compound of formula (6) . This embodiment
of the invention is illustrated in scheme 2 below:

In this embodiment the 10,11-(optionally
substituted)methanodibenzosuberol compound of formula (4)
is reacted with a nucleophile source such as a strong
acid, for example hydrogen bromide, hydrogen chloride or
methanesulfonic acid. The incipient hydronium ion is
displaced in-situ with the nudeophilic conjugate base of
the acid such as the bromide ion or chloride ion or
methanesulfonate ion to form the compound of formula (5)
where X is bromide, chloride, or methanesulfonate. The
sulfonate ester analogs of (5) may be preferably accessed
by the use of the corresponding sulfonic acid anhydride
or sulfonic acid halide. The compound of formula (5) is
reacted with pyrazine to form the compound of formula
(6). The compound of formula (6) is novel and is a
further embodiment of this invention.
Dibenzo[5.1.0]bicyclooctadiene derivatives, as
well as derivatives of related ring systems have been
found to form stable carbocations. It has been reported
that treatment of 2,3,5,6-dibenzo-4-
hydroxy[5.1.0]bicycloocta-2,5-diene with fluorosulfuric
acid at -78 °c or sulfuric acid at room temperature
provided solutions of the corresponding
dibenzohomotropylium ion, which was characterized by NMR
(see Childs, R.F.; Brown, M.A.; Anet, F.A.L.; Winstein,
S. J. Am. Chem. Soc. 1972, 94, 2175. See also: Berti,
G. J. Org. Chem. 1957, 22, 230. Looker, J.J. J. Org.
Chem. 1968, 33, 1304.) Typically, nucleophilic reactions
at the benzylic position in these systems will proceed
primarily by a SN1-type mechanism, giving rise to mixtures
of syn and anti products via a carbocation intermediate.
The present invention, however, provides the anti bromide
analog of (5) which is obtained as the exclusive product
in good yield from syn alcohol precursor (4). The
corresponding anti alcohol also gave rise to the anti
bromide analog of (5) exclusively under the same
bromination conditions. General teachings on
halogenation or sulfonation of alcohols are given in
reference texts such as March, J., Advanced Organic
Chemistry, 3rd edition, 1985, John Wiley and Sons, New
York, New York, and Larock R. C, Comprehensive Organic
Transformations, 1989 VCH Publishers, Mew York, New York.
The 10,11-(optionally substituted)
dibenzosuberylhalide or sulfonate (5) obtained as
described above is then reacted with pyrazine in a
suitable solvent, such as dichloromethane, to form the
pyrazinium salt compound of formula (6). Nucleophilic
reactions of nitrogen-containing aromatic heterocycles,
particularly pyrazine, with bromide analog of (5), result
in exclusive formation of anti quaternary salts, for
example the pyrazinium salt compound of formula (6).
A further embodiment of this invention is
represented by scheme 3 below; -

This embodiment of the invention, utilizes the
10, 11- (optionally substituted) methanodibenzosuberyl
pyrazinium salt compound of formula (6) obtained from the
processes of the invention as described above. In this
embodiment the 10, 11-(optionally
substituted)methanodibenzosuberyl pyrazinium salt
compound of formula (6), is reduced using conditions
capable of reducing the pyrazine ring to afford the
piperazine compound of formula (8). Reduction of the
pyrazinium salt compound of formula (6) can be
accomplished by hydrogenation or metal hydride
reductions, for example lithium tetrahydroaluminum
hydrides, sodium borohydride and other similar reducing
agents known to one skilled in the art. Preferred
reducing agents for the purpose of this invention include
lithium borohydride and sodium borohydride. The
reduction using lithium or sodium borohydride is
typically aided by the addition of trifluoroacetic acid.
The reduction product is typically isolated as the acid
salt by treatment of the product solution with
concentrated aqueous or anhydrous acid, for example
concentrated hydrochloric acid. Reductions of pyrazinium
salts and pyridinium salts have been reported in the
literature. See for example, Dykstra, S.J.; Minielli,
J.L.; Lawson, J.E. J. Med. Chen. 1973, 16, 1015. Bugle,
R.C.; Osteryoung, R.A. J. Oro. Chen. 1979, 44, 1719.
Ashcroft, W.R.; Joule, J.A. Heterocycles 1981, 16, 1883.
The 10,11-(optionally substituted)methano
dibenzoBuberylpiperazine acid salt (7) is neutralized to
afford the free base compound of formula (8) employing an
inorganic base such as sodium hydroxide, sodium
carbonate, bicarbonate, potassium carbonate and the like.
Most preferred is the use of powdered potassium carbonate
in protic solvents such as ethanol. One skilled in the
art is aware that aqueous inorganic bases may also be
employed. Furthermore, one skilled in the art can
appreciate that mild organic bases, such as
triethylamina, may also be employed to effect this
neutralization.
The compound of formula (8) is reacted with
either the compound of formula (9) or the compound of
formula (10) to afford the compound of formula (1).
Preparation of compounds of formula (8) and (9) are
described in U.S. patents Nos. 5,643,909 and 5,654,304,
incorporated herein by reference. The use of the
compounds of formula (8) wherein R3 is the quinolinyl
group is preferred. Most preferred is the use of
compounds of formula (8) wherein the group R3 is the
- quinolin-5-yl group. Improved procedures for preparing
the preferred embodiment of compound (8) wherein R3 is the
quinolin-5-yl group are disclosed infra in this
application. The compound of formula (1) may be
optionally reacted with a pharmaceutically acceptable
acid to form the acid salt. Preferred acids include
hydrogen chloride, hydrogen bromide, sulfuric acid,
camphorsulphonic acid and the like.
A general preparative route to the compounds of
formula (1), according to the present invention, is given
in Scheme 4 below:
Various embodiments of this invention are
incorporated in Scheme 4. Por example, in scheme 4,
steps (a) and (b) encompass one embodiment, steps (a)
through (d) encompass a further embodiment and steps (a)
through (g) encompass a further embodiment of this
invention wherein all embodiments have been described
supra. The starting material for the purpose of this
invention is 5H-dibenzo[a,d]cyclohepten-5-one.
(dibenzosuberenone), which is commercially available,
e.g., from Aldrich Chemical Company, Milwaukee, His.
Other reactants are likewise commercially available or
may be readily prepared by one of skill in the art.
Step (a)c A solution of an alkali
trihaloacetate is added over a period of about 4 to about
8 hours, preferably about 6 hours, to a solution of
dibenzosuberenone with stirring and under nitrogen while
maintaining the reaction temperature preferable from
about 160 to about 165 oC. The reaction mixture is
brought to room temperature, then poured into water and
extracted, preferably with ether. The desired 10,11-
(optionally substituted) methanodibenzosuberone is
isolated and purified by conventional means. Por
example, -the organic phase is washed with water, dried,
preferably over Na2SO4, evaporated, and the residue is
recrystallized.
Examples of alkali trihaloacetates for use in
step (a) are sodium chlorodifluoroacetate, methyl
trichloroacetate, ethyl trifluoroacetade. The preferred
alkali trihaloacetate is dependent upon the desired
substituents for R1 and R3.
Preferred solvents are diglyme, benzene, and
petroleum ether.
The skilled artisan would appreciate that other
reaction temperatures may be employed depending upon the
reactants used. For example, see Coyne and Cusic,
"Aminoalkyldibenzo(a,elcyclopropa[c] cycloheptane
Derivatives. A Series of Potent Antidepressants," J.
Med. Chem.. 1974, Vol. 17, No. 1, 72-75.
Alternatively, 10,11-methanodibenxosuberone
compounds where R1 and R2 are not identical, such as when
R1 H and R2 Cl, can be prepared as described by Coyne et
al., supra. The compound of formula (2) where R1 and R2
are both hydrogen can be prepared as described in Coyne
and Cusic, et al., supra.
Step (b): A solution of the 10,11-(optionally
substituted)methanodibenzosuberone, from step (a), in a
solvent, preferably tetrahydrofuran in methanol, is
cooled and a reducing agent, preferably lithium
borohydride or sodium borohydride, sufficient to effect
reduction is added in portions. The reaction mixture is
allowed to come to room temperature and stirred for about
1 to about 5 hours, preferably about 2 hours, then poured
into water. The product is isolated and purified by
conventional means to give the corresponding 10,11-
(optionally substituted)methanodibenzosuberol of formula
3.
The skilled artisan would appreciate that other
hydride reducing agents, including chiral and achiral
reducing agents and controlled hydrogenations should
effect this reduction.
Combined Steps (a) and (b) Procedure: To a
solution of 5H-dibenzo[a,d]cyclohepten-5-one
(dibenzosuberenone) in triethylene glycol dimethyl ether
heated from about 180°C to about 210°G is slowly added
chlorodifluoroacetic acid, lithium salt in ethylene
glycol dimethyl ether. The ethylene glycol dimethyl
ether is distilled from the reaction as the salt addition
proceeds. After the dibenzosuberenone has been consumed
as determined by analytical methods known to one skilled
in the art, the reaction is cooled to about ambient
temperature and then combined with a mixture of ethyl
acetate and diatomaceous earth. The solids are removed
by filtration and washed with ethyl acetate. The washes
and filtrate are combined and the ethyl acetate removed
by concentration under vacuum. The concentrate is cooled
to about 15 to about 30°C, followed by addition of sodium
borohydride or lithium borohydride solution. After
stirring for about 2 h the reaction is quenched by
careful addition of a solution of cone. HCl in methanol-
water (approximately 5-20%). The suspension is stirred
for about 30 min and the crude product is collected by
filtration. The filter cake is washed with 1:1 methanol-
water and dried to a dark brown solid. The crude product
is then slurried in methylene chloride, filtered and
dried to afford syn-10,11-(optionally substituted)
methanodibenzosuberol.
Step (c): A solution of the 10,11-(optionally
substituted) methanodibenzosuberol, from step (b), in a
solvent, preferably heptane, is cooled followed by
addition of a source of a leaving group, such as a
hydrogen halide, methanesulfonic acid chloride, or the
like. Bromination, for example, is effected by the
addition of hydrogen bromide while maintaining a
temperature from about 30 °C to about 100 °C, for about 2
to about 5 hours, preferably about 4 hours. The reaction
mixture is then evaporated to dryness, affording the
corresponding 5-bromo-10,11-(optionally substituted)
methanodibenzosuberane.
The use of hydrogen bromide is preferred over
other halogenatlng agents such as hydrogen chloride or
thionyl chloride to afford the anti-stereoisomer
preferentially. The 5-halo-lO,11-
difluoromethanodibenzosuberane may without further
purification, be reacted with pyrazine. Alternatively
the anti-isomer of the corresponding 5-halo-10,11-
(optionally substituted) methanodibenzosuberane may be
purified and isolated before being subjected to treatment
with pyrazine. The use of trifluoromethanesulfonic acid
chloride or p-toluene sulfonic acid chloride or
corresponding anhydride affords the corresponding
compound of formula (5) where X is trifluoromethyl or p-
toluene-sulfonate ester.
Step (d): The reaction of the anti 5-halo-
10,11-(optionally substituted)methanodibenzosuberane
compound of formula (5) or its sulfonate analog-, with
pyrazine is with or without solvent. Preferred solvents
include dimethyl sulfoxide, dimethyl sulfoxide/methylene
chloride, methylene chloride, ethyl acetate, and
tetrahydrofuran. The reaction mixture is evaporated to
dryneas and the desired anti-1-[10,11-(optionally
8ub8tituted)methanodibenzosuber-5-yl]-pyrazinium salt
compound of formula (6) may be isolated and purified.
Combined Steps (c) and (d) : The steps of
forming the 5-halo-10,11-(optionally substituted)
methanodibenzosuberane or its sulfonate analogs of
formula (5) and subsequently forming the 1-110,11-
(optionally substituted) methanodibenzo8uber-5-
yl]pyrazinium salt (formula 6), can be combined into one
operational step by distillative solvent exchange
following formation of the 5-halo-10,11-(optionally
substituted)methanodibenzosuberane or its sulfonate
analogs, and followed by addition of pyrazine.
Step (e) : Preferably the anti-1-[10,11-
(optionally substituted) methanodibenzosuber-5-
yl]pyrazinium salt of formula (6) is reduced to the desired
piperazine compound of formula (8) with, for example, a
hydride reducing agent. Preferably the reducing agent is
sodium borohydride or lithium borohydride. However, the
skilled artisan will appreciate that other reducing agents
are capable of effecting the desired reduction.
The reaction mixture may be treated with, for
example, hydrogen chloride or hydrogen bromide to form the
corresponding salt compound of formula (7) for ease of
isolation as the crystalline salt. It should be noted that
one skilled in the art may perform a controlled
hydrogenation or utilize other reducing agents such as
chiral reducing agents, biocatalytic reductions or other
methods known in the art to effect reduction of the
pyrazinium salt to the piperazine compound of formula (8) .
Step (f): A solution of the anti-1-[10,11-
(optionally substituted)methanodibenzosuber-5-
yl]piperazine acid salt of compound (7) and potassium
hydroxide in a solvent (e.g., aqueous ethanol, or aqueous
propanol, or isopropanol) is refluxed for about 0.5 to
about 2 hours, preferably about 1 hour, then cooled. The
cooled reaction mixture is concentrated, diluted with
water, extracted, dried (preferably over K2CO3), and the
organic phase is evaporated to give the corresponding
anti-1-[10,11-(optionally substituted)methanodibenzo-
suber-5-yl]piperazine compound of formula (8).
Combined Steps (£) and (g) : The desired
compound of formula (1) can be prepared by performing the
processes of steps (f) and (g) of scheme (4) sequentially
or in one operational step according to the methods of
this invention. Alternatively the compound (7) product
of this invention can be utilized to prepare compounds of
formula (1) according to the examples and methods known
in the art, (e.g. the methods described in U.S. patent
5,654,304).
For example, a suspension of anti-1-[10,11-
(optionally 8ubstituted)methanodibenzosuber-5-
yl)piperazine acid salt of compound of formula (7) and
powdered sodium carbonate in N,N-dimethylformamide or
aqueous sodium hydroxide or the like is stirred at
ambient temperature for 1 to 3 hours, preferably 1 hour.
(2R)-1-(5-quinolinyloxy)-2,3-epoxypropane compound of
formula (9) is added and the reaction mixture is heated
to about 40°C to about 100°C, preferably from about 65°C
for about 10 to about 30 hours, preferably about 19
hours. Temperature and time may vary depending on
reagents utilized. RPLC analysis is utilized to indicate
total consumption of the piperazinyl compound of formula
(8). The mixture is allowed to cool to about room
temperature, filtered through a plug of silica gel, and
eluted with ethanol. The filtrate is concentrated and
heated to about 65 °C with stirring. A solution of HCl in
ethanol is added drop-wise over about 10 minutes and the
resultant product solution is seeded, causing the
trihydrochloride salt to precipitate. The mixture is
cooled to ambient temperature and stirred for about 2
hours. The precipitate is filtered, washed with ethanol,
and dried in vacuo at about 50°C to give the crude
trihydrochlorido salt which can be further purified by
recrystallization from mathanol/ethyl acetate to provide
in the case where R1 and R3 are each fluorine, the
compound (2R) -anti-1-[4-(10,11-difluoromethano-10,11-
dihydro-5H-dibenzo[a,d]cyclohepten-5-yl) -piperazin-1-yl]-
3-quinolin-5-yloxy) -propan-2-ol trihydrochloride.
It should be understood that one of skill in the art may
react the compound of formula (8) directly with the
compound of formula (9) or formula (10) to obtain the
compound of formula (1).
A preferred embodiment of this invention is one
where the R3 group is the "quinolin-5-yl" group, and is
represented by the structure:

with a point of attachment at the 5-position counting
from the nitrogen atom and used synonymously with the
term "5-quinolyl."
Preferred are the processes according to the
invention for preparing compounds of Formula (1) where R1
and R3 are fluoro. Also preferred are the processes
according to the invention for preparing compounds of
formula (1) where A is 2-hydroxypropylene and R3 is
quinolin-5-yl. Further preferred are those processes,
which combine the above-mentioned features.
Another preferred aspect of the invention
provides a procedure that combines steps (c) and (d) of
scheme 4 to afford 1-[10,11-(optionally substituted)
methanodibenzo8uber-5-yl)-pyrazinium salt (formula (6))
in a single operational step from the 1-{10,11-
(optionally substituted)methanodibenzosuberol (4).
Preferred is the process according to the
invention for preparing the compound (2R)-5-{3-(4-(10,ll-
difluoronethanodibenzosuber-5-yl)piperazin-1-yl]-2-
hydroxypropoxy}quinoline.
A most preferred embodiment of this invention
comprises the preparation of (2R)-anti-5-{3-[4-(10,ll-
difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-
hydroxypropoxy) quinoline acid salt (1b),

where HX is an acid selected from the group comprising of
hydrogen chloride, hydrogen bromide, methane sulfonic
acid, camphorsulfonic acid, p-toluene sulfonic acid, and
sulfuric acid.
Optional Preparation of Salts of Formula (1)
The compounds of formula (1) can be converted
to the corresponding acid addition salts. The conversion
is accomplished by treatment with a stoichiometric amount
of an appropriate acid, such as hydrochloric acid (e.g.,
3 molar equivalents tp form the trihydrochloride salt) .
Typically, the free base is dissolved in a polar organic
solvent, such as methanol pr ethanol, and the acid is
added in water, methanol or ethanol. The temperature is
maintained at 0 °C to 50 °C. The corresponding salt
precipitates spontaneously or can be brought out of
solution with a less polar solvent.
The acid addition salts of the compounds of
formula (1) can be decomposed to the corresponding free
base by treatment with an excess of a suitable base.
Suitable bases include for example, ammonia and sodium
bicarbonate, typically in the presence of an aqueous
solvent, and at a temperature between O °C and 50 oC. The
free base is isolated by conventional means, such as
extraction with an organic solvent.
The following preparations and example(s) are
illustrative only and are not intended to limit the scope
of the invention in any way.

A mixture of 5-hydroxyquinoline (5.60 g, 38.6
mmol), (R)-glycidyl nosylate (10.0 g, 38.6 mmol),
powdered potassium carbonate (11.7 g, 84.9 mmol), and
N,N-dimethylfonnamide (100 mL) was stirred at ambient
temperature until HFLC analysis (40% acetonitrile/60% of
a 0.5% aqueous ammonium acetate solution, 1 mL/min, 1 =
230 run, Zorbax RX-C8 25 cm x 4.6 mm column) indicated
complete disappearance of glycidyl nosylate
(approximately 6 hours) . The reaction mixture was
filtered through paper and the filter cake was washed
with 200 mL of a 3:1 mixture of MTBE and methylene
chloride. The filtrate was washed with 200 mL of water
and the aqueous layer was extracted four times with 100
mL of 3:1 MTBE/ methylene chloride. The combined organic
layers were dried over 30 grains of magnesium sulfate and
the dried solution was then stirred with 50 grams of
basic alumina for 30 minutes. The alumina was removed by
filtration and the filter cake was washed with 200 mL of
3:1 MTBE/methylene chloride. The filtrate was
concentrated to a volume of 100 mL. 300 mL of MTBE was
added, and the solution was again concentrated to 80 mL.
After heating to 50 °C, the solution was treated with 160
mL of heptane drop-wise over 15 minutes, allowed to cool
to 40 °C, and seeded, causing the formation of a
crystalline precipitate. The mixture was stirred for two
hours at ambient temperature and then at 0-5 °C for an
additional 2 hours. The crystals were filtered, washed
with cold heptane, and dried to provide 5.68 g (73.2%) of
(2R)-1-(5-quinolinyloxy)-2,3-epoxypropane as white
needles.
mp 79-81 °C
[a]25D -36.4° (c 2.1, EtOH)
1H NMR (500 MHz, CDCl3) d 2.83 (dd, J = 4.8, 2.7 Hz, 1H),
2.97 (m, 1H), 3.48 (m, 1H), 4.10 (dd, J = 11.0, 6.0 Hz,
1H), 4.43 (dd, J = 11.0, 2.7 Hz, 1H), 6.85 (d, J = 7.8
Hz, 1H), 7.38 (dd, J = 8.5 Hz, 4.1 Hz. 1H). 7.59 (m, 1H),
7.71 (d, J = 8.5 Hz, 1H), 8.61 (m, 1H), 8.90 (m, 1H) .
Preparation 2
1- (4-Benzofurazanyloxy) -2, 3-epoxypropane
Sodium hydride (620 mg; 60% oil dispersion) was
added in portions to benzofurazan-4-ol (1.74g) in
dimethylformamide (30 ml). The mixture was heated at 50
°C. for 30 min. Epibromohydrin (1.6 ml) was added and the
mixture was heated at 60 °C for 2 hours. The reaction
mixture was poured into water and extracted with ethyl
acetate. The organic phase was washed with water, dried
over Na2SO4, and evaporated. The residue was
chromatographed on silica gel (50% ethyl acetate/hexane)
to give 1-(4-benzofurazanyloxy)-2,3-epoxypropane (1.6 g),
mp 75 °C.
Example 1
(2R)-anti-1-[4-(10,11-difluoromethano-10,11-dihydro-5H-
dibenzo[a, d) cyclohepten-5-yl)-piperazin-1-yl] -3-quinolin-
5-yloxy)-propan-2-ol trihydrochloride

Preparation of the above compound is
exemplified in the following preparative steps.
Step a
10,11-Difluoromethanodibenzosuberone

A solution of sodium chlorodifluoroacetate (350
g) in diglyme (1400 mL) was added dropwise over 4 to 8
hours, preferably over 6 hours, to a solution of
dibenzosuberenone (25 g) in diglyme (500 mL), with
overhead stirring and under nitrogen, maintaining the
reaction temperature at 160-165 °C. Heating was continued
until the dibenzosuberenone was satisfactorily consumed
(90-100%) as determined by analytical techniques such as
Gas Chromatography or Thin Layer Chromatography known to
one skilled in the art. The reaction mixture was then
cooled to room temperature, poured into water (1.8 L) and
extracted with ether (1.8 L) . The organic phase was .
washed with water, dried over Na2SO4. and evaporated. The
residue was recrystallized from ethanol, then from
acetone/hexane to give 14 g of 10,11-
difluoromethanodibenzosuberone, mp 149.6 °C. Flash
chromatography of the combined mother liquors on silica
gel, eluting with 20% acetone/hexane, gave an additional
6.5 g of the desired material.
Gas Chromatography (GC) Conditions: Column JW
Scientific DB-1, Initial Temperature 150 °C for 5 min, 10
°C/min ramp, Final temp 250 °C for 5 min. tR: desired
product, 11.5 min; starting material, 12.3 min.

A solution of 10,11-difluoromethanodibenzo-
suberone (20.4 g) in THF/KeOH (1:2, 900 ml) was cooled in
an ice bath. Sodium borohydride (12 g) was added in
portions. The cooling bath was removed, the reaction
mixture was stirred at ambient temperature for 2 hours,
and poured into water. The product was filtered off,
washed with water, and dried to give 20 g of ayn 10,11-
difluromethanodibenzosuberol.
mp 230.1-230.6 °C.
Optional Combined Steps (a) and (b)
(10,11-Dif luoromethanodibenzosuberol)

To a solution of 103.1 g (0.500 mol) of
dibenzosuberenone (2) in 515 mL of triethylene glycol
dimethyl ether heated to 180 °C was added, over 7 hours,
293.3 g (2.15 mol) of chlorodifluoroacetic acid lithium
salt (as a 53 % by weight solution in ethylene glycol
dimethylether). The ethylene glycol dimethylether was
allowed to distill from the reaction as the salt addition
proceeded. The GC analysis of an aliquot indicated that
all of the dibenzosuberenone had been consumed. The
reaction was cooled to ambient temperature and then
combined with 400 mL of ethyl acetate and 75 g of
diatomaceous earth. The solids were removed by
filtration and washed with 300 mL of ethyl acetate. The
washes and filtrate were combined and the ethyl acetate
was removed by concentration under vacuum leaving 635 g
of dark liquid. The dark liquid was cooled to 18 °C and
to this was added, over 15 min, 6.62 g (0.175 mol) of
sodium borohydride (as a 12% by wt solution in 14 M
NaOH). After stirring for 2 h the reaction was quenched
by careful addition of 900 mL of a 1:3.5:4.5 solution of
cone. HCl-methanol-water. The suspension was stirred for
30 min and the crude product was collected by filtration,
washed with 600 mL of 1:1 methanol-water and dried to
126.4 g of dark brown solid. The crude product was
slurried with 600 mL of methylene chloride, washed twice
with 150 mL portions of methylene chloride, and dried to
91.6 g (71%) of 10,11-difluoromethanodibenzosuberol as a
solid.
Gas Chromatography (GC) Conditions: Column JW
Scientific DB-1, Initial Temperature 150 °C for 5 min, 10
°C/min ramp. Final temp 250 °C for 5 min. tR:
intermediate, 11.5 min; desired product (alcohol), 11.9
min; starting material, 12.3 min.
Step c
5-bromo-10, 11-dif luoromethanodibenzosuberane

A slurry of the 10, 11-difluoramethanodibenzo-
suberol (3.0 g, 11.6 mmol, 1.0 equiv.) in heptane (24 mL)
was treated with 48% HBr (1.58 mL, 14.0 mmol, 1.2 equiv.)
and the reaction was heated at reflux with vigorous stirring
for 2.5 hr. Solvent was then removed by atmospheric
distillation (bp 95 - 98 °C) until c.a. 9 mL of distillate
was collected. The reaction was cooled and treated with
EtOAc (15 mL), Na2SO4 (1.5 g) and activated charcoal (750
mg). The mixture was stirred at RT for 15 min and filtered
through hyflo. The filter cake was washed with 50:50
EtOAc:heptane (3 x 3 mL) and the filtrate was concentrated
in vacuo to provide the product as a crystalline solid,
mp 119 oC (3.46 g corr., 93%)
1HNMR (500 MHz CDCl3) d 7.20-7.41 (8H, m) , 5.81 (1H, s) ,
3.41 (2H, d, J = 12.5 Hz)
13CNMR (126 MHz CDCl3) d 141.3, 141.2, 133.5, 130.1, 129.8,
128.3, 128.2, 112.9, 110.6, 110.5, 108.3, 53.6, 30.2, 30.1,
30.0
Anal. Calcd. For C16H11BrF2: C. 59.84; H, 3.45. Found: C,
60.13; H, 3.50.
Combined Steps (c) and (d)
anti-1-[10,11-difluoromethanodibenzosuber-5-yl]-
pyrazinium hydrobromide salt

A stirred slurry of the 10,11-difluorodibenzo-
methanosuberol (56.2 g of 91.8 wt%, or 51.6 g corr., 0.2
mol) in heptane (420 mL) was treated with 48% HBr (27.2
mL, 0.24 mol, 1.2 equiv.) and the thick slurry was heated
at reflux with vigorous stirring. After 1.5 hr at
reflux, the solvent was removed by atmospheric
distillation to provide approximately 50% concentration.
The reaction was cooled and diluted with BtOAc. Activated
charcoal and Na2SO4 were added. After stirring at RT for
1 hour, the mixture was filtered through a pad of hyflo
and the filter-cake was rinsed with 50:50 EtOAc:heptane.
The filtrate was concentrated by vacuum distillation.
The residue was diluted with EtOAc (200 mL) and
concentrated in vacuo until -200 mL of distillate was
collected. The residue was diluted to 100 mL with EtOAc
and treated with pyrazine (48.0 g, 0.6 mol, 3.0 equiv)
and DMSO (50 mL), resulting in an endotherm to 6 °C. The
solution was warmed to 30-32 °C and stirred for 18 hours.
The reaction mixture was diluted with methyl t-butyl
ether (MTBE) (500 mL) and stirred for 15 min. Light-
yellow solid was filtered, washed with MTBE (200 mL) and
dried to provide the pyrazinium salt analog, anti-1-
[10, 11-dif luoromethanodibenzo8uber-5-yl]-pyrazinium
hydrobromide.
m.p. 165 °C (68.2 g, 85%)
1HNMR (500 MHz DMSO-d6)d 9.46 (2H, d, J = 2.7 Hz), 8.77
(2H, t, J = 1.7 Hz), 7.74 (2H, d, J = 7.5 Hz), 7.42-7.55
(6H, m), 7.27 (1H, s), 3.19 (2H, d, J = 12.6 Hz)
13CNMR (126 MHz DMSO-d6) 6 152.5, 135.8, 135.4, 134.4,
133.2, 132.1, 129.9, 129.6, 112.9, 110.6, 108.3, 77.4,
28.7, 28.6; FD MS: m/e 321 (M - Br)
Anal. Calcd. For C20H15BrF2N2: C, 59.87; H, 3.77; N, 6.98.
Found: C, 59.84; H, 3.66; N, 6.83.
Alternatively the anti isomer of the 5-halo-
10,11-(optionally substituted) methanodibenzosuberane
halogenation product could be prepared and isolated by
the procedure of preparation 3, before being subjected to
treatment with pyrazine.
Step e
1,1-dif luoro-6-[1-piperazinyl]-1, 1aa, 6a, 10ba-
tetrahydrodibenzo[a, e]cyclopropa [c]cycloheptene
hydrochloride (or)
((6S,1aS,10bR)-1,1-difluoro-1,6,10b,1a-
tetrahydrodibenzo[b, e] cyclopropa[1,2-f][7)annulen-6-
yl)piperazine hydrochloride

A stirred slurry of the pyrazinium salt from
above (10.0 g, 24.9 mmol) in EtOAc (50 mL) was treated
directly with NaBH4, (2.07 g, 54.8 mmol, 2.2 equiv) and the
slurry was cooled to 15 °C (cold-water bath).
Trifluoroacetic acid (6.34 mL, 82.3 nmol, 3.30 equiv) was
added drop-wise over a 15 minute period with the reaction
temperature maintained between 22 and 25 °C during
addition with periodic cooling (cold-water bath) . Upon
completion of addition, the reaction was allowed to stir
at ambient temperature for 1.5 hours. At this time the
reaction was cooled to 10 °C and quenched by cautious
addition of 2.5 M NaOH (50mL) . The mixture was stirred
at room temperature for 15 minutes and the layers were
separated. The organic phase was washed with 2.5 M NaOH
(2 X 50 mL), 50% saturated NaCl solution (50 mL) and
dried (Ma3SO4 - 6.0 g). EtOAc (50 mL) was added to the
organic phase during the above workup from various
transfers and washes, giving a total EtOAc volume of 80-
100 mL at the end of the workup. This solution was
treated with concentrated HC1 (2.08 mL of a 12 M
solution, 24.9 nmol, 1.0 equiv.) and the slurry was
stirred at room temperature for 2 hours then at 0-5 °C for
15 min. White solid was filtered, washed with cold EtOAc
(10 mL) and dried to provide the product as a powder,
m.p. 274-278 oC (dec) (7.67g with a potency of 85.6%, or
6.56 g corrected for free-base, 81%)
1HNMR (500 MHz DMSO-d6) d 9.41 (2H, br. s), 7.17-7.31 (8H,
m), 4.17 (1H, s), 3.52 (2H, d, J = 12.4 Hz), 3.11 (4H,
br. s), 2.48-2.51 (4H, m)
13CNMR (126 MHz DMSO-d6) d 142.3, 133.4, 130.5, 129.6,
129.0, 128.4, 115.9, 113.6, 111.3, 76.2, 49.0, 43.6,
29.2, 29.1, 29.0; FD MS: m/e 326 (M +).
Anal. Calcd. Por C20H21ClF2N2: C, 66.20; H, 5.83; N, 7.72.
Found: C, 66.08; H, 5.90; N, 7.72.
Combined steps (f) and (g)
(2R)-anti-1-[4-(10,11-difluoromethano-10,11-dihydro-5H-
dibenzo[a, d] cyclohepten-5-yl)-piperazin-1-yl]-3-quinolin-
5-yloxy)-propan-2-ol trihydrochloride
A suspension of l,l-difluoro-6[1-piperazinyl]-
1,1aa,6a,10ba-tetrahydrodibenzo[a,e]cyclopropa[c]-
cycloheptene hydrochloride (5.41 g, 14.9 mmol) and
powdered sodium carbonate (3.16 g, 29.8 mmol) in 54 mL of
3A ethanol was stirred at ambient temperature for 1 hour.
(2R)-1-(5-Quinolinyloxy)-2,3-epoxypropane (3.00 g, 14.9
mmol) was added in one portion and the reaction mixture
was heated to 65 °C for 19 hours. HPLC analysis (Gradient
system with solvent A (acetonitrile) and solvent B (0.02M
sodium monophosphate buffer containing 0.1% triethylamine
adjusted to pH 3.5 with phosphoric acid) as follows: 0-
12 min. 30% solvent A / 70% solvent B; 12-30 min, linear
gradient from 30% to 55% solvent A / 70% to 45% solvent
B; 30-35 min, 55% solvent A / 45% solvent B, 1 mL/min, 1
= 240 run, Synchropak SCD-100 25 cm x 4.6 mm column)
indicated total consumption of starting material. The
mixture was allowed to cool to room temperature, filtered
through a pre-wetted (EtOH) 14 gram plug of silica gel,
and eluted with an additional 90 mL of ethanol. The
filtrate was concentrated to a volume of approximately 60
mL and heated to 65 °C with stirring. A solution of HCl
in ethanol (16.1 g at 0.135 g/g of solution, 59.6 mmol)
was added drop-wise over 10 minutes and the resultant
product solution was seeded, causing the trihydrochloride
salt to precipitate. The mixture was allowed to cool to
ambient temperature and stirred slowly for 2 hours. The
precipitate was filtered, washed with ethanol, and dried
in vacuo at 50 °C to give the crude trihydrochloride salt
which was further purified by recrystallization from
methanol/ethyl acetate to provide 7.45 g (78.4%) of (2R)-
anti-1-[4-(10, 11-difluoromethano-10, 11-dihydro-5H-
dibenzo[a, d] cyclohepten-5-yl) -piperazin-1-yl] -3-quinolin-
5-yloxy)-propan-2-ol trihydrochloride as a solid.
Although the use of the syn 10,11-
difluorodibenzomethanosuberol and the anti 5-bromo-10,11-
dif luoromethanodibenzosuberane have been described and
exemplified above, the skilled artisan will appreciate
that formation of the anti-pyrazinium salt compound of
formula (6) can be effectively accomplished with either
the syn or the trans isomer of 5-halo-10,11-(optionally
substituted)methanodibenzosuberane compound of formula
(5) . This is possible by virtue of the intermediacy of a
10,11-(optionally substituted)methanodibenzosuberane
tropylium ion in the formation of the anti-pyrazinium
salt compound of formula (6).
Likewise, one skilled in the art is aware that
the use of the syn isomer of 10,11-(optionally
substituted)-methanodibenzosuberol (4) is not critical to
the practice of this invention. The anti isomer of
10,11-(optionally substituted)methanodibenzosuberol would
be equally effective. This is because the formation of
5-halo-10,11-(optionally substituted)-methanodibenzo-
suberane (5) proceeds via the corresponding tropylium ion
intermediate which in the case of the bromide provides
the anti isomer of the compound of formula (5)
preferentially, by the method of this invention.
Additionally, the present invention provides a
novel hydrate crystal form of (2R)-anti-5-{3-[4-(10,11-
difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-
hydroxypropoxy}quinoline trihydrochloride ("Hydrate I").
A number of methods are available to characterize
crystalline forms of organic compounds. Among these
methods are differential scanning calorimetry, solid
state NMR spectrometry, infra-red spectroscopy, and x-ray
powder diffraction. The x-ray powder diffraction pattern
is very useful for distinguishing between different
crystalline forms of a compound.
X-ray powder diffraction analysis can be
readily performed as follows. After lightly grinding the
sample with an agate mortar and pestle, the sample is
loaded into a sample holder for the x-ray powder
diffraction measurement. The x-ray powder diffraction
patterns are measured using a Siemens D5000 x-ray powder
diffractometer equipped with a CuKa source (X=1.54056A).
A NIST traceable digital hygrometer (model 11-661-16) was
used to measure the actual relative humidity in the
sample chamber. The 0% R.H. XRD patterns were obtained
by pre-drying the samples over P2O5 for at least one week.
Interplanar spacings and peak intensities for the most
prominent features were measured using a double-
derivative peak picking method. Hydrate I has a typical
XRD pattern with the following interplanar spacings (d)
in Angstroms, wherein the interplanar spacings have the
following typical relative intensities (I/Io). The error
of measurement is +/- 0.04 A. X-ray peaks with I/Io of 5%
or greater were reported in Table 1, below. The cutoff
was chosen arbitrarily.
TABLE 1
d value Angstroa I/IO (%)
29.89 6.6
9.93 14.8
7.95 100
7.69 6.9
7.40 15.8
7.22 7.9
6.61 8.4
5.95 6.7
5.08 5.5
4.45 9.1
3.99 5.4
3.96 11.2
3.83 6.6
3.68 6.3
3.96 11
3.55 5.6
3.36 10.4
It is well known in the crystallography art that,
for any given crystal form, the relative intensities of
the diffraction peaks may vary due to a number of
factors, including the effects of preferred orientation
which result from a particular crystal morphology, and
particle size. Where the effects of preferred
orientation and/or particle size are present, peak
intensities (that is, the I/Io value) are altered, but the
characteristic peak positions of the polymorph are
unchanged. See, e.g., The United States Pharmacopoeia
#23, National Formulary #18. pages 1843-1844, 1995.
The effects of preferred orientation can be greatly
reduced using a sample that is prepared in a manner that
minimizes this effects, such as the use of a well ground
sample. Hydrate I may be characterized as having an X-
ray diffraction pattern which comprises peaks
corresponding to the following d spacings: 7.95 +/-0.04 A
when obtained at 22 ±2°C and 31 ±10% relative humidity
from a copper radiation source. Preferably, a properly
prepared sample of Hydrate I may be characterized as
having an X-ray diffraction pattern which comprises peaks
corresponding to the following d spacings: 9.93, 7.95,
4.45, and 3.36 +/- 0.04 A when obtained at 22 ±2oC and 31
±10% relative humidity from a copper radiation source.
Additionally, as the skilled artisan would
appreciate. Hydrate I may also be characterized by solid
state NMR spectroscopy. Solid state NMR (13C) analysis
was performed using a Varian Unity 400 MHz spectrometer
operating at a carbon frequency of 100.580 MHz, equipped
with a complete solids accessory and Varian 7 mm VT
CP/MAS probe. Acquisition parameters were as follows:
90° proton r.f. pulse width 4.0 µs, contact time 1.0 ms,
pulse repetition time 5 s, MAS frequency 7.0 kHz,
spectral width 50 kHz. and acquisition time 50 ms.
Chemical shifts were referenced to the methyl group of
hexamethylbenzene (5 = 17.3 ppm) by sample replacement.
Solid state 13C chemical shifts reflect not only the
molecular structure of Hydrate I, but also the electronic
environment of the molecule in the crystal. The
diagnostic 13C resonances of Hydrate I, which appear in
the 100-160 ppm chemical shift range, are 105.7, 106.5,
111.0, 113.0, 118.8, 119.5, 130.0, 132.3, 133.7, 134.7,
136.4, 136.7, 141.3, 142.6, 145.8, 148.1, 152.6, and
153.6 ppm.
The precise conditions under which Hydrate I is
formed may be empirically determined and it is only
possible to give a number of methods which have been
found to be suitable in practice. Thus, for example.
Hydrate I may be prepared by crystallization under
controlled conditions. It is understood that the present
process can utilize (2R)-anti-5-{3-[4-(10,11-
difluoromethanodibenzoBuber-5-yl)piperazin-1-yl]-2-
hydroxypropoxy}quinoline trihydrochloride regardless of
its hydration state or crystalline state. In particular,
it can be prepared either from (2R)-anti-5-{3-[4-{10,11-
difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-
hydroxypropoxy)quinoline trihydrochloride or by
recrystallization of previously isolated (2R)-anti-5-{3-
[4-(10, 11-difluoromethanodibenzosuber-5-yl)piperazin-1-
yl]-2-hydroxypropoxy)quinoline trihydrochloride.
Mixtures of water and water-miscible solvents are used
for the crystallization of Hydrate I. In general, the
use of water miscible solvents such as alkyl ketones,
e.g. acetone, butanone, and the like; alkyl nitriles,
e.g. acetonitrile, propionitrile, and the like; and alkyl
alcohols, e.g. methanol, ethanol, isopropanol, and the
like; is preferred. In order to dissolve the starting
material it may be helpful to warm the solvent system.
It may be advantageous to add "seeds" of Hydrate I
to the solution in order to induce crystallization.
Hydrate I is readily soluble and can be filtered off from
the crystallization solution, if desired after cooling,
and washed and dried. If desired. Hydrate I prepared as
above may be further crystallized using similar
conditions for crystallization to those described above.
The present invention is further illustrated by
the following examples and preparations. These examples
and preparations are illustrative only and are not
intended to limit the invention in any way.
Hydrate I was prepared by recrystallizing a
compound of Example 1, as obtained by the previously
defined process, as an ethanol wetcake, vacuum dried,
then humidified to replace the ethanol. Therefore the
present invention further encompasses a process of
preparing Hydrate I comprising: a) forming an ethanol
wetcake of (2R)-anti-5-{3-[4-(10,11-
difluoromethanodibenzosuber-5-yl) piperazin-1-yl]-2-
hydroxypropbxy}quinoline trihydrochloride, b) drying the
ethanol wetcake by vacuum to obtain dry (2R)-anti-5-{3-
[4- (10,11-dif luoromethanodiben2osuber-5-yl)piperazin-1-
yl]-2-hydroxypropoxy}quinoline trihydrochloride, and c)
humidifying the dry (2R)-anti-5-{3-[4-(10,11-
difluoromethanodibenzosuber-5-yl)piperazin-1-yl)-2-
hydroxypropoxy}quinoline trihydrochloride to obtain
Hydrate I.
The following solvates may be converted to
Hydrate I by humidification to replace the organic
solvents. This list of solvates are for example purposes
only. The skilled artisan will appreciate that the
organic solvents used for recrystallization are non-
specific and maybe used in a multitude of combinations.
Methanol/H2O solvate was prepared by dissolving
a compound of Example 1 in MeOH (10 mL) at ambient
temperature with stirring. To the stirred solution was
added EtOAc (20 mL). The product wetcake was isolated by
vacuum filtration, washed with EtOAc (15 mL) and dried in
a vacuum oven at ambient temperature for -16 hours.
Yield = 579 mg.
Ethanol/H2O solvate was prepared by suspending a
compound of Example 1 in 3A EtOH (20 mL) . The stirred
suspension was heated to reflux and additional 3A EtOH
(10 mL) was added to dissolve the solids. The solution
was allowed to reflux (78.5oC) for -20 minutes, at which
time the heat source was turned off and the solution was
allowed to slowly cool to room temperature. The solution
became turbid by -36oC. The microcrystalline product was
isolated by vacuum filtration, washed with 3A EtOH (2-3
mL), and air dried. Yield = 141 mg (significant product
loss accompanied transfer of the highly electrostatic
particles).
IPA/H2O solvate was prepared by dissolving a
compound of Example 1 in MeOH (10 mL) at ambient
temperature with stirring. To the stirred solution was
added IPA (10 mL) dropwise to induce crystallization.
The solid product was isolated by vacuum filtration,
washed with ZPA (20 mL), and dried in a Buchner funnel
over an air stream. Yield = 509 mg.
n-Propanol/H2O solvate was prepared by
dissolving a compound of Example 1 in H2O (1 mL) and n-
PrOH (1 mL). To the stirred solution was added n-PrOH
(68 mL). The solution was then rotovapped to dryness to
produce a tacky solid. n-PrOH (20 mL) was added and the
solid product was isolated by vacuum filtration, washed
with n-PrOH (5 mL), and air-dried. Yield = 293 mg.
THF/H2O solvate was prepared by dissolving a
compound of Example 1 in MeOH (10 mL) at ambient
temperature with stirring. To the stirred solution was
added THF (20 mL) dropwise to induce crystallization.
The solid product was isolated by vacuum filtration,
washed with THF (20 mL), and dried in a Btichner funnel
over an air stream. Yield = 520 mg.
Acetone/H2O solvate was prepared by dissolving a
compound of Example 1 in MeOH (10 mL) at ambient
temperature with stirring. To the stirred solution was
addad acetone (20 mL) dropwisa to induce crystallization.
The solid product was isolated by vacuum filtration,
washed with acetone (15 mL), and dried in a BOchner
funnel over an air stream. Yield = 472 mg.
Acetonitrile/H2O solvate was prepared by
suspending a compound of Example 1 in ACM (25 aL). The
stirred suspension was then heated and H2O (3 mL) was
added to dissolve the solids. The solution was cooled to
ambient temperature, at which time EtOAc (50 mL) was
added dropwise. The solid product was isolated by vacuum
filtration, washed with EtOAc (5 mL), and air-dried.
Yield = 555 mg.
DMAC/acetone/H2O solvate was prepared by
dissolving a compound of Example 1 in DMAC (5 mL) with
stirring at ambient temperature. A small amount of
undissolved, gummy solid was removed by gravity
filtration. Acetone (20 mL) was then added dropwise to
the stirred solution and the resulting solid was allowed
to slurry overnight. The yellow solid was isolated by
vacuum filtration onto cellulose acetate filter paper and
washed with acetone. Yield = 389 mg.
DMF/H2O solvate was prepared by suspending a
compound of Example 1 in DMF (13 mL) and water (~0.2 mL)
was added dropwise to the stirred suspension, effecting
rapid dissolution of the solids. Crystallization was
induced by dropwise addition of iPrOAc (15 mL) followed by
continued slurrying for 24 hrs. The solid product was
isolated by vacuum filtration and washed with iPrOAc. The
tacky yellow solid was characterized as a wetcake.
DMSO/ACN/H2O solvate: a compound of Example 1
was dissolved in DMSO (3 mL) with stirring at room
temperature. ACN (20 mL) was then added dropwise to the
stirred solution. The solid product was isolated by
filtration onto cellulose acetate filter paper and washed
with several mL of ACN. The resulting wetcake was dried
at 50°C for 20 min. to give 284 mg of bright yellow
powder.
The present invention further provides a method
of treatment for a drug resistant disease comprising
coadministering to a mammal in need thereof a resistance
modulating amount of Hydrate I and an effective amount of
a treatment drug for said drug resistant disease.
Preferably the disease is cancer. Preferably, the
treatment drug is a cancer chemotherapeutic agent.
The present invention further provides a method
of treatment for a multidrug resistant disease comprising
coadministering to a mammal in need thereof a multidrug
resistance modulating amount of Hydrate I and an
effective amount of a treatment drug for said multidrug
resistant disease. Preferably, the treatment drug is a
cancer chemotherapeutic agent.
The present invention further provides a method
for enhancing bioavailability of a pharmaceutically
active agent to the brain, comprising coadministering to
a mammal in need thereof a therapeutically effective
amount of said drug and Hydrate I sufficient enough to
allow said drug to cross the blood-brain barrier and
enter the brain. Preferable the active agent is an HIV
protease inhibitor. Examples of such protease inhibitors
contemplated by the present invention are NELFINAVIR,
which is preferably administered as the mesylate salt at
750 mg three times per day (U.S. Patent No. 5,484,926,
herein incorporated by reference); RITONAVIR, which is
preferably administered at 600 mg twice daily (U.S.
Patent No. 5,484,801, herein incorporated by reference);
SAQUINAVIR, which is preferably administered at the
mesylate salt at 1,200 mg three times per day (U.S.
Patent No. 5,196,438, herein incorporated by reference);
INDINAVIR, which is preferably administered as the
sulfate salt at 800 mg three times per day (U.S. Patent
No. 5,413,999, herein incorporated by reference); and
AMPRENAVIR, which is preferably administered at 1,200 mg
twice daily (U.S. Patent No. 5,585,397, herein
incorporated by reference). The skilled artisan would
recognize that this list is not exhaustive.
Additionally, the skilled artisan would recognize that
the protease inhibitors' administration to a patient may
vary from the preferred.
The present invention further provides the use
of Hydrate I in combination with an effective amount of a
treatment drug, or a pharmaceutically acceptable salt
thereof, for the manufacture of a medicament for the
treatment of a drug resistant disease. Preferably the
disease is cancer. Preferably, the treatment drug is a
cancer chemotherapeutic agent.
The invention further provides the use of
Hydrate I in combination with an effective amount of a
treatment drug, or a pharmaceutically acceptable salt
thereof, for the manufacture of a medicament for the
treatment of a multidrug resistant disease. Preferably,
the treatment drug is a cancer chemotherapeutic agent.
The present invention further provides the use
of Hydrate I in combination with a pharmaceutically
active agent, or a pharmaceutically acceptable salt
thereof, for the manufacture of a medicament for
enhancing bioavailability of the pharmaceutically active
agent to the brain, comprising coadministering to a
mammal in need thereof a therapeutically effective amount
of said drug and Hydrate I sufficient enough to allow
said drug to cross the blood-brain barrier and enter the
brain. Preferable the active agent is an HIV protease
inhibitor.
Preferably, the present invention relates to a
pharmaceutical formulation comprising Hydrate I; one or
more pharmaceutical carriers, diluents, or excipients;
and optionally a treatment drug.
When employed as a pharmaceutical, Hydrate I is
usually administered in the form of pharmaceutical
compositions. These compositions can be administered by
a variety of routes including oral, rectal, transdermal,
and intranasal. Such compositions are prepared in a
manner well known in the pharmaceutical art and comprise
Hydrate I.
The term "substantially pure" refers to the crystal
phase purity of Hydrate I. In practice we have found
that small amounts of other crystalline forms do not
adversely affect the advantageous properties of Hydrate
I. According to the present invention substantially pure
refers to Hydrate I which is greater than 90%, preferably
greater than 95% of the total crystalline material.
This invention also includes pharmaceutical
compositions which contain Hydrate I (referred to as
"active ingredient" herein below) associated with
pharmaceutically acceptable carriers. In making the
compositions of this invention, the active ingredient is
usually mixed with an excipient, diluted by an excipient
or enclosed within such a carrier which can be in the
form of a capsule, sachet, paper or other container.
When the excipient serves as a diluent, it can be a solid
or semi-solid which acts as a vehicle, carrier, or medium
for the active ingredient. Thus, the compositions can be
in the form of tablets, pills, powders, lozenges,
sachets, cachets, emulsions, aerosols, ointments
containing, for example, up to 10% by weight of the
active compound, tablet, soft and hard gelatin capsules,
suppositories, and sterile packaged powders.
Some examples of suitable excipients include
lactose, dextrose, sucrose, sorbitol, mannitol, starches,
gum acacia, calcium phosphate, alginates, tragacanth,
gelatin, calcium silicate, microcrystalline cellulose,
polyvinylpyrrolidone, cellulose, sterile water, syrup,
and methyl cellulose. The formulations can additionally
include: lubricating agents such as talc, magnesium
stearate, and mineral oil; wetting agents; emulsifying
and suspending agents; preserving agents such as methyl-
and propylhydroxy-benzoates; sweetening agents; and
flavoring agents. The compositions of the invention can
be formulated so as to provide quick, sustained or
delayed release of the active ingredient after
administration to the patient by employing procedures
known in the art.
The compositions are preferably formulated in a unit
dosage form, each dosage containing from about 5 to about
100 mg, more usually about 10 mg to about 30 mg, of the
active ingredient. The term "unit dosage forms" refers
to physically discrete units suitable as unitary dosages
for human subjects and other mammals, each unit
containing a predetermined quantity of active material
calculated to produce the desired therapeutic effect, in
association with a suitable pharmaceutical excipient.
Preferably, Hydrate I is employed at no more than about
20 weight percent of the pharmaceutical composition, more
preferably no more than about 15 weight percent, with the
balance being pharmaceutically inert carrier (s).
Hydrate I is effective over a wide dosage range and
is generally administered in a pharmaceutically effective
amount. It, will be understood, however, that the amount
of the compound actually administered will be determined
by a physician, in the light of the relevant
circumstances, including the condition to be treated, the
chosen route of administration, the actual compound
administered, the age, weight, and response of the
individual patient, the severity of the patient's
symptoms, and the like.
For preparing compositions such as tablets, the
active ingredient is mixed with a pharmaceutical
excipient to form a solid pre-formulation composition
containing a homogeneous mixture of a compound of the
present invention. When referring to these pre-
formulation compositions as homogeneous, it is meant that
the active ingredient is dispersed evenly throughout the
composition so that the composition may be readily
subdivided into equally effective unit dosage forms such
as tablets, pills and capsules. This solid pre-
formulation is then subdivided into unit dosage forms of
the type described above containing from, for example,
0.1 to about 500 tag of the active ingredient of the
present invention.
The tablets or pills of the present invention may be
coated or otherwise compounded to provide a dosage form
affording the advantage of prolonged action. Por
example, the tablet or pill can comprise an inner dosage
and an outer dosage component, the latter being in the
form of an envelope over the former. The two components
can separated by enteric layer which serves to resist
disintegration in the stomach and permit the inner
component to pass intact into the duodenum or to be
delayed in release. A variety of materials can be used
for such enteric layers or coatings, such materials
including a number of polymeric acids and mixtures of
polymeric acids with such materials as shellac, cetyl
alcohol, and cellulose acetate.
Compositions for inhalation or insufflation include
liquids, suspensions, and powders. The liquid or solid
compositions may contain suitable pharmaceutically
acceptable excipients as described supra. Preferably the
compositions are administered by the oral or nasal
respiratory route for local or systemic effect.
Compositions in preferably pharmaceutically acceptable
solvents may be nebulized by use of inert gases.
Nebulized solutions may be breathed directly from the
nebulizing device or the nebulizing device may be
attached to a face masks tent, or intermittent positive
pressure breathing machine. Solution, suspension, or
powder compositions may be administered, preferably
orally or nasally, from devices which deliver the
formulation in an appropriate manner.
The following formulation examples illustrate the
pharmaceutical compositions of the present invention
which comprise Hydrate I, as active ingredient.
Formulation Example 1
Hard gelatin capsules containing the following
ingredients are prepared:
Ingredient (mg/capsule)
Active Ingredient 30.0
Starch 305.0
Magnesium stearate 5.0
The above ingredients are mixed and filled into hard
gelatin capsules in 340 mg quantities.
Formulation Example 2
A tablet formula is prepared using the ingredients below:
Ingredient (mg/tablet)
Active Ingredient 25.0
Cellulose, microcrystalline 200.0
Colloidal silicon dioxide 10.0
Stearic acid 5.0
The components are blended and compressed to form
tablets, each weighing 240 mg.
Formulation Example 3
A dry powder inhaler formulation is prepared containing
the following components:
Ingredient Weight %
Active Ingredient 5
Lactose 95
The active ingredient is mixed with the lactose and the
mixture is added to a dry powder inhaling appliance.
Formulation Example 4
Tablets, each containing 30 mg of active ingredient, are
prepared as follows:
Ingredient (mg/tablet)
Active Ingredient 30.0 mg
Starch 45.0 mg
Microcrystalline cellulose 35.0 mg
Polyvinylpyrrolidone
(as 10% solution in sterile water) 4.0 mg
Sodium carboxymethyl starch 4.5 mg
Magnesium stearate 0.5 mg
Talc 1.0 mg
Total 120 mg
The active ingredient, starch and cellulose are
passed through a No. 20 mesh U.S. sieve and mixed
thoroughly. The solution of polyvinyl-pyrrolidone is
mixed with the resultant powders, which are then passed
through a 16 mesh U.S. sieve. The granules so produced
are dried at 50° to 60°C and passed through a 16 mesh
U.S. sieve. The sodium carboxymethyl starch, magnesium
stearate, and talc, previously passed through a No. 30
mesh U.S. sieve, are then added to the granules which,
after mixing, are compressed on a tablet machine to yield
tablets each weighing 150 mg.
Formulation Example 5
Capsules, each containing 40 mg of medicament are made as
follows:
Ingredient (mg/capsule)
Active Ingredient 40.0 mg
Starch 109.0 mg
Magnesium stearate 1.0 mg
Total 150.0 mg
The active ingredient, starch, and magnesium stearate are
blended, passed through a No. 20 mesh U.S. sieve, and
filled into hard gelatin capsules in 150 mg quantities.
Formulation Example 6
Suppositories, each containing 25 mg of active ingredient
are made as follows:
Ingredient Amount
Active Ingredient 25 ng
Saturated fatty acid glycerides to 2,000 mg
The active ingredient is passed through a Mo. 60 mesh
U.S. sieve and suspended in the saturated fatty acid
glycerides previously melted using the minimum heat
necessary. The mixture is then poured into a suppository
mold of nominal 2.0 g capacity and allowed to cool.
Formulation Example 7
Ingredient (mg/capsule)
Active Ingredient 15.0 mg
Starch 407.0 mg
Magnesium stearate 3.0 mg
Total 425.0 mg
The active ingredient, starch, and magnesium stearate are
blended, passed through a No. 20 mesh U.S. sieve, and
filled into hard gelatin capsules in 560 mg Quantities.
Formulation Example 9
A subcutaneous formulation may be prepared as follows:
Ingredient Quantity
Active Ingredient 1.0 mg
corn oil 1 ml
Formulation Example 10
A topical formulation may be prepared as follows:
Ingredient Quantity
Active Ingredient 1-10 g
Emulsifying Wax 30 g
Liquid Paraffin 20 g
White Soft Paraffin to 100 g
The white soft paraffin is heated until molten. The
liquid paraffin and emulsifying wax are incorporated and
stirred until dissolved. The active ingredient is added
and stirring is continued until dispersed. The mixture
is then cooled until solid.
Another preferred formulation employed in the
methods of the present invention employs transdemal
delivery devices ('patches'). Such transdemal patches
may be used to provide continuous or discontinuous
infusion of the compounds of the present invention in
controlled amounts. The construction and use of
transdermal patches for the delivery of pharmaceutical
agents is well known in the art. See, e.g., D.S. Patent
5,023,252, issued June 11, 1991, herein incorporated by
reference. Such patches may be constructed for
continuous, pulsatile, or on demand delivery of
pharmaceutical agents.
Frequently, it will be desirable or necessary to
introduce the pharmaceutical composition to the brain,
either directly or indirectly. Direct techniques usually
involve placement of a drug delivery catheter into the
host's ventricular system to bypass the blood-brain
barrier. One such implantable delivery system used for
the transport of biological factors to specific
anatomical regions of the body is described in U.S.
Patent 5,011,472 which is herein incorporated by
reference.
Indirect techniques, which are generally preferred,
usually involve formulating the compositions to provide
for drug latentiation by the conversion of hydrophilic
drugs into lipid-isoluble drugs. Latentiation is
generally achieved through blocking of the hydroxy,
carbonyl, sulfate, and primary amine groups present on
the drug to render the drug more lipid soluble and
amenable to transportation across the blood-brain
barrier. Alternatively, the delivery of hydrophilic drugs
may be enhanced by intra-arterial infusion of hypertonic
solutions which can transiently open the blood-brain
barrier.
Other suitable formulations for use in the present
invention can be found in Remington's Pharmaceutical
Sciences, Mace Publishing Company, Philadelphia, PA, 17th
ed. (1985).
As noted above, Hydrate I is suitable for use in a
variety of drug delivery systems described above.
Additionally, in order to enhance the in vivo serum
half-life of the present compound, it may be
encapsulated, introduced into the lumen of liposomes,
prepared as a colloid, or other conventional techniques
may be employed which provide an extended serum half-life
of the compounds. A variety of methods are available for
preparing liposomes, as described in, e.g., Szoka, et
al., U.S. Patent Nos. 4,235,871, 4,501,728 and 4,837,028
each of which is incorporated herein by reference.
The amount of Hydrate I administered to the patient
will vary depending upon the purpose of the
administration, such as prophylaxis or therapy, the state
of the patient, the manner of administration, and the
like. In therapeutic applications, compositions are
administered to a patient already suffering from
Alzheimer's disease in an amount sufficient to at least
partially arrest further onset of the symptoms of the
disease and its complications. An amount adequate to
accomplish this is defined as "therapeutically effective
dose." Amounts effective for this use will depend on the
judgment of the attending clinician depending upon
factors such as the degree or severity of the disease
state in the patient, the age, weight and general
condition of the patient, and the like. Preferably, for
use as therapeutics. Hydrate I is administered at dosages
ranging from about 1 to about 500 mg/kg/day.
The present invention provides a process for
preparing Hydrate I which comprises crystallizing (2R)-
anti-5-(3-[4-(10, 11-difluoromethanodibenxosuber-5-
yl)piperazin-1-yl]-2-hydroxypropoxy)quinoline
trihydrochloride from a solution of water and a water
miscible solvent under conditions which yields Hydrate I.
WE CLAIM:
1. A process for preparing a compound of formula (1)

wherein A is -CH2-CH2-, -CH2-CHRa-CH2-, -CH2-CHRa-CH2-CH2- and Ra
is OH;
R1 is H, F, Cl, or Br;
R2 is H, F, Cl, or Br; and
R3 is heteroaryl or phenyl, each substituted or unsubstituted with F, Cl, Br,
CF3, CN, NO2, or OCHF2;
or the pharmaceutically acceptable salts thereof, comprising the steps of:
(a) reacting a compound of formula (4)

with a nucleophile source such as herein described to form a compound of
formula (5)

wherein X is a leaving group; selected from the group consisting of Br, Cl,
OMs and OTs
(b) reacting a compound of formula (5) with pyrazine to provide a
compound of formula (6)

(c) reducing the compound of formula (6) by hydrogenation or metal
hydride reduction to provide a compound of formula (8)

(d) reacting a compound of formula (8) with either:
(i) an epoxy compound of formula (9)

wherein R3 is as defined above, and n is an integer 1 or 2; or
(ii) a halo compound of formula (10)

wherein R3 is as defined above, X1 is halo, and m is 2, 3 or 4; and
(e) optionally forming a pharmaceutically acceptable salt from the
compound produced in step (d).
2. The process as claimed in claim 1 wherein the nucleophile source is selected from
the group comprising of HCl, HBr, HI, sulfonic acids, sulfonic anhydrides and sulfonic
acid halides.
3. The process as claimed in claim 1 wherein R1 and R2 are each F and X is Br.
4. The process as claimed in claim 1, 2, or 3 wherein R3 is quinolin-5-yl.
5. The process as claimed in claim 4, wherein the salt of a compound of formula (1) is
the trihydrochloride salt.
6. The process as claimed in claim 1 wherein the reducing agent for reducing the
compound of formula (6) is a lithium tetrahydroaluminum hydride.
7. The process as claimed in claim 1 wherein the reducing agent for reducing the
compound of formula (6) is lithium borohydride or sodium borohydride.
8. The process as claimed in claim 7 wherein the reduction step is aided by addition of
trifluoroacetic acid.
This invention provides a process to prepare 10,11-(optionally substituted)methanodibenzosuberane derivatives. The
invention also provides an intermediate in this process.

Documents:


Patent Number 225450
Indian Patent Application Number IN/PCT/2001/001254/KOL
PG Journal Number 46/2008
Publication Date 14-Nov-2008
Grant Date 12-Nov-2008
Date of Filing 27-Nov-2001
Name of Patentee ELI LILLY AND COMPANY
Applicant Address LILLY CORPORATE CENTRE, INDIANAPOLIS, IN 46285
Inventors:
# Inventor's Name Inventor's Address
1 HUFF, BRET, EUGENE 2825 WOLVERINE WAY, ZIONSVILLE, IN 46077
2 LE TOURNEAU, MICHAEL, EDWARD 6024 MCCLELLAN COURT, INDIANAPOLIS, IN 46254
3 BUSH, JULIE, KAY 10671 RED BERRY COURT FISHERS, IN 46038
4 REUTZEL-EDENS, SUSAN, MARIE 4824 EAGLES WATCH LANE, INDIANAPOLIS, IN 46254
5 WILSON, THOMAS, MICHAEL 1193 GREENLAWN SPEEDWAY, IN 46224
PCT International Classification Number C07D 295/00
PCT International Application Number PCT/US2000/09826
PCT International Filing date 2000-05-26
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/137,283 1999-06-03 U.S.A.