| Title of Invention | NOVEL OXAZOLIDINONE COMPOUNDS HAVING ANTIBACTERIAL PROPERTY, PROCESS FOR THEIR PREPARATION AND PHARMACEUTICAL COMPOSITIONS CONTAINING THEM |
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| Abstract | The present invention relates to novel oxazolidinone compounds of the general formula (I). ~here R I, R2, R3, yl, y2, y3 and Z are as defined in the description; their derivatives, their analogs, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutical compositions containing them. |
| Full Text | Filed of the Invention The present invention relates to novel oxazolidinone compounds, their derivatives, their analogs, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutical compositions containing them. More particularly, the present invention relates to novel oxazolidinones of the general formula (I). their derivatives, their analogs, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutical compositions containing them. The present invention also relates to a process for the preparation of the above said novel compounds, their derivatives, their analogs, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutical compositions containing them. The present invention also relates to novel intermediates, methods for their preparation and their use in the preparation of compounds of formula (I). Oxazolidinones are useful as antibacterials (J. Med. Chem., 1996, 39, 673), antihistamines and anti allergic agents (EP 291,244), anticonvulsants (DE 3,915,184), treating cognition disorders, anti psychotics, platelet ant aggregators, antidepressants, sedatives, hypnotics, monoamine oxidase inhibitors (WO 97/13768) and as chiral auxiliaries (Aldrichimica Acta, 1982, 15 23) in asymmetric synthesis. Background of the Invention Since the discovery of penicillin, pharmaceutical companies have produced more than one hundred antibacterial agents to combat a wide variety of bacterial infections. In the past several years, due to the misuse of these antibiotics there has been rapid emergence of bacterial resistance to several of these antibiotics. The multidrug resistance among these bacterial pathogens may also be due to mutation leading to more virulent clinical isolation, the most disturbing milestone has been the acquisition of resistance to vancomycin, an antibiotic generally regarded as the agent of last resort for serious Gram-positive infections. This growing multidrug resistance has recently rekindled interest in the search for new structural class of antibiotic that inhibit or kill these bacteria possibly by novel mechanisms. A problem of larger dimension is the increasing incidence of the more virulent, methicillin-resistant Staphylococcus aureus (MRSA) among clinical isolates found worldwide. As with vancomycin resistant organisms, many MRSA strains are resistant to most of the known antibiotics, but MRSA strains have remained sensitive to vancomycin. However, in view of the increasing reports of vancomycin resistant clinical isolates and growing problem of bacterial resistance, there is an urgent need for new molecular entities effective against the emerging and currently problematic Gram-positive organisms. Recently, several oxazolidinones have been discovered, which inhibit protein synthesis by binding to the 50S-ribosomal subunit which is close to the site to which chloramphenicol and lincomycin bind but their mode of action is mechanistically distinct from these two antibiotics. The new class of oxazolidinones of the present invention is useful for the treatment of a number of resistant and sensitive gram-positive strains both in vitro and in vivo. Some of the hitherto known compounds described in the prior art are outlined below: (i) International Patent Application WO 93/23384 discloses compounds of formula (Ila) where Y represents a hydrogen atom, (C1-C6)alkyl or aryl, OH, 0(C1-C6)alkyl, 0-vinyl, O-phenyl, 0-C(=0)(C1-C6)alkyl, -0-C(=0)-phenyl (phenyl can be substituted with one to three F, CI, OCH3, OH, NH2, or (C1-C4)alkyl) or 0-C(=0)-0-CH3, S-(C1-C6)alkyl, S02-(C1-C6)alkyl, -S02-N(R^)2, (where R3 is independently hydrogen, (C1-C4)alkyl or phenyl which can be substituted with one to three F, CI, OCH3, OH, NH2, or (C1-C4)alkyl); .C(==0)-(C1-C6)alkyl, -C(=0)-0-(C1-C6)alkyl, -C(=0)-N(R')2, -C(=0)-CH(R')N(R')2, -C(=0)-CH(R4)-NH-C(NH)-NH2 (where R1 is an amino acid side chain); -N(R3)2, -N(CH2)m (where m is 2-6 and forms a cyclic structure with the nitrogen atom and where one or more carbon atoms where R5 is OH, OCH3, CH2OH, CH2OCH3, CO2CH3, CO2C2H5, R6 represents CH3 or hydrogen, R7 represents CH2 or C(=0), R8 represents hydrogen or =0, p is 1 or 2, R9 represents O, S, S(0), SO2, CH2, NH, NCH3, NC2H5, NCHO, NCOCH3 or NCO2CH3, wherein each occurrence of said (C1-C6)alkyl may be substituted with one or more F, CI, Br, I, 0R1 C00R1 CN, SR1 or R1 (where R1 is a hydrogen or (C1-C4)alkyl); X and Z are independently (C1-C6)alkyl, (C3-Ci2)cycloalkyl or hydrogen or X and Z form a (C0-C3) bridging group, preferably X and Z are hydrogen; U, V and W are independently (C1-C6)alkyl, F, CI, Br, hydrogen or a (C1-C6)alkyl substituted with one or more of F, CI, Br or I, preferably U and V are F and W is hydrogen; R is hydrogen, (C1-C12)alkyl, (C3-C12)cycloalkyl, (C1-C6)alkoxy, (C1-C6)alkyl substituted with one or more F, CI, Br, I or OH , n is 1 or 2; and q is 0-4 inclusive. An example of this class of compounds is shown in formula (IIb) wherein R1 represents -NHC(=0)Ra wherein Ra represents (C1-C4)alkyl; R2 and R3 represent hydrogen or fluoro; R4 and R5 are independently hydrogen or methyl; R6 represent pyridyl, optionally substituted by substituents selected from (C1-C4)alkyl (optionally substituted), halo, trifluoromethyl, (C1-C4)alkyl-S(0)n- (wherein n is 0, 1 or 2), (C1-C4)alkyl S02 amino, (d-C4)alkanoylamino, carboxy, hydroxy, amino, (C1-C4)alkylamino, di-(C1-C4)alkylamino, (C1- C4)alkoxycarbonyl, carbamoyl, N-(C1-C44)alkylcarbamoyl, di-(N-(C1-C44)alkyl)carbamoyl (wherein the (C1-C44)alkyl group on groups in the last two mentioned carbamoyl groups is optionally substituted by hydroxy, (C1-C44)alkoxy or (C1-C44)alkoxycarbonyl), (C2-C4)alkenyl (optionally substituted by carboxy or (C1-C44)alkoxycarbonyl), (C1-C44)alkoxy, cyano, or nitro groups. wherein X represents O, S, SO, SO2, SNR10 or SONR1; R represents hydrogen, (C1-C48)alkyl optionally substituted with one or more of the following : F, CI, hydroxy, (C1-C48)alkoxy, (C1-C8)acyloxy or -OCH2Ph or R represents (C3-C6)cycloalkyl, amino, (C1-C48)alkylamino, (C1-C8)dialkylamino or (C1-C48)alkoxy; R1 represents hydrogen except when X is O, then R1 can be hydrogen, CH3, cyano, -CO2H, CO2R or (CH2)mR11 (m is 1 or 2); R2 represents independently hydrogen, F or CI; R^ represents hydrogen or CH3; R10 independently represents hydrogen, (C1-C4)alkyl (optionally substituted with chloro, fluoro, hydroxy, (CrC8)alkoxy, amino, (C1-C8)alkylamino, or (C1-C48)dialkylamino) or p-toluenesulfonyl; R11 represents hydrogen, hydroxy, OR, OCOR, NH2, NHCOR or N(R10 and n is 0, 1 or 2. An example of this class of compounds is shown in formula (IIf) (iv) International Patent Application WO 95/25106 discloses compounds of formula (IIg) where R is hydrogen atom, (C1-C8)alkyl, (C3-C6)cycloaIkyl, amino, (C1-C8)alkylamino, (Cr C8)dialkylamino, (C1-C8)alkoxy or (C1-C8)halogen alkyl; R1 and R3 are each and independently represents hydrogen atom, halogen atom, (C1-C8)alkyl, (C3-C6)cycloalkyl, -(CH2)m-0R11 or -C(=0)-R ; X and Y are each and independently represents hydrogen atom, halogen atom; R4 and R5 are each and independently represents hydrogen atom, (C1-C8)alkyl, (C1-C8)aIkoxy, (C1-C8)alkylthio, -(CH2)m-0R51 -0-(CH2)m-0R51 -NR42R52 -N=CH-NR44R55 -C(=0)-NR42R52 or -(CH2)m-C(=A)-R41 or they may combine together to form =0, =NR43 =S, =CR44R54 or an optionally substituted, unsaturated or saturated 5 or 6 membered hetero ring having 1-3 hetero atoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom; R11 and R12 are each and independently represents hydrogen atom, (C1-C8)alkyl or methoxymethyl; R41 is hydrogen atom, -(CH2)m-0H, (C1-C8)alkyl, (C1-C8)alkoxy, -O-CH2-O-C(=0)-R11 or -(CH2)m-C(=0)-OR11 R42 and R52 are each and independently represents hydrogen atom, -(CH2)m-0R11 (CrC8)alkyl, -C(=0)-R41 -C(=0)-NR11R12 -(CH2)p-phenyl, thiazol-2-yl or they may combine together to form a pyrrolidino group, a piperidino group, a piperazino group, a morpholino group or a thiomorpholino group, each of which may be substituted by (C1-C8)alkyl or -(CH2)m-OH; R43 is hydrogen atom, -OR51 (C]-C8)alkyl, (d-C8)alkoxy, -(CH2)p-phenyl, NR42R52 -NH-C(=NH)-NH2, [l,2,4]triazol-4-yl or cyano; R44 and R55 are each and independently represents hydrogen atom, (C1-C8)alkyl, -C(=0)-R41 or -(CH2)p-phenyl; R51 is hydrogen atom, (C1-C8)alkyl substituted by one or more hydroxy; (C2-C8)alkenyl, (C1-C8)halogenalkyl, -(CH2)n,-0R11 -(CH2)m-C(=0)-R41 -C(=0)-(CH2)m-0R44 or tosyl; A is oxygen atom or ethyleneketal; — is a double bond or a simple bond; m's are each and independently 0, 1 or 2; n is 0 or 1; p's are each and independently 1, 2, 3 or 4; An example of this class of compounds is shown in formula (IIh) (C3-C6)cycloalkyl, amino, (C1-C8)alkylamino, (C1-C8)dialkylamino, (C1-C8)alkoxy; R6 is O, S, NR10 CR11R12 (0R)2, where R is (C1-C6)alkyl; 0(CH2)m O, (SR)2 where R is (C1-C6)alkyl; S(CH2)mS; R7 is H, (C1-C8)alkyl optionally substituted with one or more of the following : F, CI, -CN, OH, (CrC8)alkoxy, (C1-C8)acyloxy, (C1-C8)alkoxycarbonyl, phenyl; (C1-C8)acyl optionally substituted with one or more of the following : hydroxy, (C1-C8)alkoxy, (d-C8)acyloxy; (CrC8)alkoxycarbonyl, carboxamide optionally substituted with a (C1-C4)alkyl or phenyl on the carboxamide nitrogen; phenyl, optionally substituted with one or more of the following : halogen, CN, (CrC3)alkoxy, (C1-C3)alkoxycarbonyl, (C1-C4)alkyl optionally substituted with one or more of F or (C1-C3) alkoxy; R8 and R9 are independently selected from H, (C1-C8)alkyl optionally substituted with one or more of the following : F, CI, -CN, OH, (Cr C8)alkoxy, (C1-C8)acyloxy, (C1-C8)alkoxycarbonyl, phenyl; (C1-C8)acyl optionally substituted with one or more of the following : hydroxy, (C1-C8)alkoxy, (C1-C8)acyloxy, amino, (Ci-C4)acylamino, amino (C1-C4)acylamino; benzoyl optionally substituted with one or more of the following F, CI, hydroxy, (C1-C8)alkoxy, (C1-C8)acyloxy, amino, (CrC4)acylamino, (C1-C4) alkoxycarbonylamino; (C1-C8)alkoxycarbonyl, benzyloxycarbonyl, tertbutoxycarbonyl; carboxamide optionally substituted with a (C1-C4)alkyl or phenyl on the carboxamide nitrogen; trifluoracetyl, C0(C1-C6 alkyl); R10 is H, OR7 NHR7 (C1-C8)alkyl optionally substituted with phenyl; R11 and R12 are independently selected from H, F, (C1-C4)alkyl optionally substituted with halogen, hydroxy, (CrC4)alkoxy, (CrC4)alkoxycarbonyl, phenyl; (C1-C8)acyl, (C1- C4)alkoxycarbonyl, CN; R17 is O or S; R18 and R19 are independently selected from H, (C1- * C4)alkyl optionally substituted with halogen, hydroxy, (C1-C4)alkoxy; OH, (C1-C4)alkoxy optionally substituted with hydroxy or (C1-C4)alkoxy; NR8R9 -0C(0) (C1-C4)alkyl; R20 is H, R' is of the formula -NHC(=0)(C1-C4)alkyl, -NHS(0)n(C1-C4)alkyl, wherein n is 0, 1 or 2 or R1 is hydroxy; R2 and R3 are independently hydrogen or fluoro; R4 is hydrogen, methyl, ethyl or oxo; R5 is hydrogen, (C1-C6)alkyl, (C2-C6)alkenyl, (C2-C6)alkynyl, or of the formula R^(CH2)m wherein m is 1-4 and R6 is trifluoromethyl, difluoromethyl, fluoromethyl, {C\-C4)alkoxy, (C,-C4)alkyl,S(0)p wherein p is 0, 1 or 2, (C1-C6)alkanoyloxy, di-(N-(C1-C4)alkyl)amino, N-((C1-C4)alkyl)(C1-C4)alkanoylamino, cyano, carboxy, {C1-C4)alkoxycarbonyl, carbamoyl, -di-(N-(C1-C4)alkyl)carbamoyl, N-((C1-C4)alkyl)(C1-C4)alkanesulphonamido, N'-((C1-C4)alkyl)-di-(N-'-(C1-C4)alkyl)ureido or of the formula -OC(=0)NR(R8) or N(R9)S02NR7(R8) wherein R7 and R8 are independently hydrogen or (C1-C4)alkyl and R9 is (C1-C4)alkyl; or m is 2-4 and R6 is hydroxy, (C1-C4)alkanoylamino, amino, (C1-C4)alkylamino, (CrC4)alkanesulphonamido, ureido, di-(N3-(CrC4)alkyl)ureido or of the formula NHS02NR7(R8); An example of this compound is shown in fig (III) R1 is of the formula -NHC(=0)Ra wherein R^ is (C1-C4)alkyl; R2 and R3 are independently hydrogen or fluoro; R4 and R5 are independently hydrogen or methyl; R6 is a 6-membered heteroaryl ring containing 2 or 3 ring nitrogen atoms as the only ring heteroatoms and optionally substituted by substituents selected from (C1-C4)alkyl (optionally substituted), halo, trifluoromethyl, (C1-C4)alkylS(0)n- (wherein n is 0, 1 or 2), (C1-C4)alkylS(0)2 amino, (C1-C4)alkanoylamino, carboxy, hydroxy, amino, (C1-C4)alkylamino, di(C1-C4)alkylamino, (C1-C4)alkoxycarbonyl, carbamoyl, N-(CrC4)alkylcarbamoyl, -di-(N-(C]-C4)alkyl)carbamoyl, [wherein (C1-C4)alkyl group or groups in the last two mentioned carbamoyl substituents is optionally substituted by hydroxy, (C1-C4)alkoxy or (C1-C4)alkoxycarbonyl], (C2-C4)alkenyl (optionally substituted by carboxy or (C1-C4)alkoxycarbonyl), (CrC4)alkoxy, cyano or nitro; An example of this compound is shown in fig (IIn) Summary of the Invention With an objective to develop novel compounds effective against a number of human and veterinary pathogens, including gram-positive aerobic bacteria such as MRSA, streptococci and enterococci as well as anaerobic organisms such as Bacteroides spp, Clostridia spp. species and acid-fast organisms such as Mycobacterium tuberculosis, Mycobacterium avium and Mycobacterium spp,, we focussed our research to develop new compounds effective against the above mentioned organisms. Efforts in this direction have led to the preparation of compounds having general formula (I) as defined above. The main objective of the present invention is therefore, to provide novel Oxazolidinones of the general formula (I) as defined above and their derivatives, their analogs, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutical compositions containing them, or their mixtures having enhanced activities, without toxic effect or with reduced toxic effect. Another objective of the present invention is to provide a process for the preparation of novel oxazolidinones of the formula (I) as defined above and their derivatives, their analogs, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts and their pharmaceutically acceptable solvates. Still another objective of the present invention is to provide pharmaceutical compositions containing compounds of the general formula (I), their analogs, their derivatives, their tautomers, their stereoisomers, their polymorphs, their salts, solvates or their mixtures in combination with suitable carriers, solvents, diluents and other media normally employed in preparing such compositions. Yet another objective of the present invention is to provide novel intermediates of formulae (III), (VIII), (X), (XIV), (XVII), (XVIII), (XX) and a process for their preparation and their use in the preparation of compounds of formula (I). wherein R1 represents halo, azido, thioalcohol, 0R4 NHR4 or N(R4)2, where R4 represents hydrogen atom, or substituted or unsubstituted groups selected from acyl, thioacyl, (C1-C6)alkoxycarbonyl, (C3-C6)cycloalkoxythiocarbonyl, (C2-C6)alkenyloxycarbonyl, (C2- C6)alkenylcarbonyI, aryloxycarbonyl, (C1-C6)alkoxythiocarbonyl, (C:- C6)alkenyloxythiocarbonyl, aryloxythiocarbonyl, -C(=0)-C(=0)-alkyl, -C(=0)-C(=0)-aryl, - C(=0)-C(=0)-alkoxy, -C(-0)-C(=0)-aryloxy, -(C=S)-S-alkyl, -(C=S)-NH2, -(C=S)-NH-alkyl, -C(=S)-N-(alkyl)2, -C(=S)-NH-alkenyl, (C=S)-(C=0)-alkoxy, -(C=S)-(C=0)-aryloxy, -C(=S)- 0-(C=0)-alkyl, C(=S)-C(=S)-alkyl, -C(=S)-C(=S)-aryl, -C(=S)-C(=S)-alkoxy, -C(=S)-C(-S)- aryloxy, S(0)2(C1-C6)alkyl, S(0)2aryl, thiomorpholinylthiocarbonyl or pyrrolidinylthiocarbonyl; R and R may be same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa NRa ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen or substituted or unsubstituted (Cr C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1- C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group or substituted or unsubstituted groups selected from (C1- C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (CrC6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)aIkyl, arylcarbonylamino(C1-C6)alkyl, (CrC6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates. Suitable groups represented by R4 may be selected from hydrogen atom, (C1-C4yjacyl group such as -C(=0)H, -C(=0)CH3, -C(=0)CH2CH3, -C(=0)(CH2)2CH3, -C(-0)(CH2)3CH3, -C(=0)(CH2)4CH3, -C(=0)(CH2)5CH3, -C(=0)Ph and the like, the acyl group may be substituted; thio(C1-C7)acyl group such as -C(=S)H, -C(-S)CH3, -C(-S)CH2CH3, -C(=S)Ph and the like, the thioacyl group may be substituted; (C1-C6)alkoxycarbonyl group containing (C1-C6)alkyl group which may be linear or branched such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl and the like, the (C1-C6)alkoxycarbonyl group may be substituted; (C3-C6)cycloalkoxythiocarbonyl group such as cyclopropoxythiocarbonyl, cyclobutoxythiocarbonyl and the like, the (C3-C6)cycloalkoxythiocarbonyl may be substituted; (C2-C6)alkenylcarbonyl such as ethenylcarbonyl, propenylcarbonyl, butenylcarbonyl and the like, the (C2-C6)alkenylcarbonyl may be substituted; (C2-C6)alkenyloxycarbonyl group such as ethenyloxycarbonyl, propenyloxycarbonyl, butenyloxycarbonyl and the like, the (C2-C6)alkenyloxycarbonyl may be substituted; aryloxycarbonyl group such as phenoxycarbonyl, benzyloxycarbonyl group and the hke, the aryloxycarbonyl group may be substituted; (C1-C6)alkoxythiocarbonyl group such as CH3O-C(=S)-, C2H50-C(=S)- C3H70-C(=S)- and the hke, which may be substituted; (C2-C6)alkenyloxythiocarbonyl group such as ethenyloxythiocarbonyl, propenyloxythiocarbonyl, butenyloxythiocarbonyl and the like, the (C2-C6)alkenyloxythiocarbonyl group may be substituted; aryloxythiocarbonyl group such as PhO-C(=S)-, BzO-C(=S)- and the Hke, which may be substituted; -C(=0)-C(=0)-alkyl group such as -C(=0)-C(=0)methyl , -C(=0)-C(=0)ethyl, -C(=0)-C(=0)propyl and the Hke, which may be substituted; -C(=0)-C(=0)-aryl group such as -C(=0)-C(=0)phenyl, -C(=0)-C(=0)naphthyl and the Hke, which may be substituted; -C(=0)-C(=0)-alkoxy group such as -C(=0)-C(=0)methoxy, -C(=0)-C(=0)ethoxy, -C(=0)-C(=0)propyloxy and the Hke, which may be substituted; -C(=0)-C(=0)-aryloxy group such as -C(=0)-C(=0)phenyloxy, -C(=0)-C(=0)benzyloxy, which may be substituted; -(C=S)-S-alkyl such as -(C=S)-S-methyl, -(C=S)-S-ethyl, -(C=S)-S-propyl and the Hke, which may be substituted; -(C=S)-NH2; -(C=S)-NH-alkyl such as -(C=S)-NH-methyl, -(C=S)-NH-ethyl, -(C=S)-NH-propyl and the Hke, which may be substituted; -C(=S)-N-(alkyl)2 such as -C(=S)-N-(methyl)2, -C(=S)-N-(ethyl)2, -C(=S)-N-(propyl)2 and the Hke, which may be substituted; -C(=S)-NH-alkenyl such as -C(=S)-NH-ethenyl, -C(=S)-NH-propenyl, -C(=S)-NH-butenyl and the Hke, which may be substituted; -(C=S)-(C=0)-alkoxy such as -(C=S)-(C=0)-methoxy, -(C=S)-(C=0)-ethoxy, -(C=S)-(C=0)-propoxy and the Hke, which may be substituted; -(C=S)-(C=0)-aryloxy such as -(C=S)-(C=0)-phenyloxy, -(C=S)-(C=0)-naphthyloxy and the like, which may be substituted; -C(=S)-0-(C=0)-alkyl such as -C(=S)-0-(C=0)-methyl, -C(=S)-0-(C=0)-ethyi, -C(=S)-0-(C=0)-propyl and the Hke, which may be substituted; -C(=S)-C(=S)alkyl group such as -C(=S)-C(==S)methyl, -C(=S)-C(=S)ethyl, -C(=S)-C(=S)propyl and the Hke, which may be substituted; -C(=S)-C(=S)aryI group such as -C(=S)-C(=S)phenyl, -C(=S)-C(=S)naphthyI and the Hke, which may be substituted; -C(=S)-C(=S)-alkoxy group such as -C(=S)-C(=S)methoxy, -C(=S)-C(=S)ethoxy, C(=S)-C(=S)propyloxy and the Hke, which may be substituted; -C(=S)- C(=S)aryloxy group such as -C(=S)-C(=S)phenyloxy, -C(=S)-C(=S)benzyloxy, which may be substituted; S(0)2(C1-C6)alkyl group such as SO2CH3, SO2C2H5, SO2C3H7, S02CH(CH3)CH3 and the like, which may be substituted; S(0)2aryl such as S(0)2phenyl, S(0)2tolyl, S(0)2naphthyl and the hke, which may be substituted, thiomorpholinythhiocarbonyl or pyrrohdinylthiocarbonyl. When the groups represented by R4 are substituted, the substituents may be selected from halogen atom such as chlorine, fluorine, bromine and iodine; hydroxy, amino, cyano, nitro, alkoxy, aryl, hydroxyaryl, pyridyl, hydroxyalkyl, alkoxyaryl or carboxyl and its derivatives. Suitable groups represented by R and R may be selected from hydrogen, halogen atom such as fluorine, chlorine or bromine; (C1-C6)alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl, n-pentyl, iso-pentyl, n-hexyl and the like; halo(C1-C6)alkyl group such as halomethyl, haloethyl, halopropyl, trihalomethyl and the like, wherein the halo group is selected from fluorine, chlorine, bromine or iodine; cyano, nitro; SR^, NR^ ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group such as methyl, ethyl, propyl, isopropyl and the like; halo(CrC6)alkyl such as halomethyl, haloethyl, halopropyl, haloisopropyl and the like, where the halo group is selected from fluro, chloro, bromo or iodo. Suitable groups represented by Z may be selected from S, O, =CH or NR where R represents hydrogen or substituted or unsubstituted (C1-C6)alkyl such as methyl, ethyl, propyl and the like, which may be substituted; (C2-C6)alkenyl such as ethenyl, propenyl, butenyl and the like, which may be substituted; (C1-C6)cycloalkyl such as cyclopropyl, cyclobutyl and the like, which may be substituted; (CrC6)alkoxy such as methoxy, propoxy, isopropoxy and the like, which may be substituted; aryl group such as phenyl, naphthyl and the like, which may be substituted; aralkyl such as benzyl, phenethyl and the like, which may be substituted; aryloxy such as phenyloxy, naphthyloxy and the like, which may be substituted; (C1-C6)alkylcarbonyl such as methylcarbonyl, ethylcarbonyl, propylcarbonyl and the like, which may be substituted; arylcarbonyl such as phenylcarbonyl, naphthylcarbonyl and the like, which may be substituted; (C1-C6)alkoxycarbonyl such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl and the like, which may be substituted; or aryloxycarbonyl such as phenyloxycarbonyl, naphthyloxycarbonyl and the like, which may be substituted. The substituents on Rb are selected from hydroxy, halogen, pyrrolidinylthiocarbonyl, nitro, amino, alkoxy, carboxyl or cyano. Y represents =0 or =S group, Y2 and Y3 are selected from hydrogen, halogen such as fluorine, chlorine, bromine or iodine; cyano, nitro, formyl, hydroxy, amino, =0, =S group, substituted or unsubstituted (C1-C6)alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl and the like; hydroxy(C1-C6)alkyl such as hydroxymethyl, hydroxyethyl hydroxypropyl and the hke, which may be substituted; (C1-C6)alkoxy(C1-C6)alkyl group such as methoxymethyl, methoxyethyl, ethoxyethyl, ethoxymethyl, methoxypropyl, propoxymethyl propoxyethyl and the like, which may be substituted; (C1-C6)alkoxycarbonyl group such as methoxycarbonyl, ethoxycarbonyl and the like, which may be substituted; carboxy(C1-C6)alkyl such as CH3-COOH, CH3-CH2-COOH and the like, which may be substituted; (C1- C6)alkylsulfonyl group such as methylsulfonyl, ethylsulfonyl and the like, which may be substituted; (C1 -C6)alkylcarbonylamino(C 1 -C6)alkyl groups such as methylcarbonylaminomethyl, ethylcarbonylaminomethyl, methylcarbonylaminoethyl and the like, which may be substituted; arylcarbonylamino(C1-C6)alkyl such as phenylcarbonylaminomethyl, phenylcarbonylaminoethyl and the like, which may be substituted; (C1-C6)alkylcarbonyloxy(C1-C6)alkyl group such as methylcarbonyloxymethyl, ethylcarbonylxoymethyl, methylcarbonyloxyethyl, propylcarbonyloxymethyl, propylcarbonyloxyethyl, propylcarbonyloxypropyl and the like, which may be substituted; amino(CrC6)alkyl such as aminomethyl, aminoethyl, aminopropyl and the like, which may be substituted; (C1-C6)alkylamino such as methylamino, ethylamino, propylamino and the like, which may be substituted; arylamino such as phenylamino, benzylamino and the like, which may be substituted; (C1-C6)alkoxy group such as methoxy, ethoxy, propoxy, isopropoxy and the like, which may be substituted; aryl group such as phenyl, naphthyl and the like, which may be substituted; aryloxy group such as phenoxy, naphthyloxy and the like, the aryloxy group may be substituted; aralkyl such as benzyl, phenethyl, C6H5CH2CH2CH2, naphthylmethyl and the like, the aralkyl group may be substituted; heteroaryl groups such as pyridyl, thienyl, furyl, pyrrolyl, oxazolyl, thiazolyl, pyrazolyl, imidazolyl, oxadiazolyl, tetrazolyl, benzopyranyl, benzofuranyl and the like, which may be substituted; heteroaralkyl such as imidazolemethyl, imidazoleethyl, pyridylmethyl, furyl methyl, oxazolemethyl, imidazolyl and the like, which may be substituted; heterocyclyl group such as pyrrolidinyl, piperidinyl, morpholinyl piperazinyl and the like; heterocycloalkyl groups such as pyrrolidinemethyl, piperidinemethyl morpholinemethyl, piperazinemethyl and the like, which may be substituted. When the groups represented by Y2 and Y3 are substituted, the substituents may be selected from hydroxy, nitro, cyano, amino, TBSO, halogen atom, (C1-C6)alkyl. (C1-C6)alkoxy, (C3-C6)cycloalkyl, aryl, benzyloxy, acyl or acyloxy groups. Suitable cyclic structure formed by Y2 and Y3 when present on adjacent carbon atoms which they are attached may be selected from substituted or unsubstituted benzene, pyridine, pyrrolidine, furan, thiophene, morpholine, piperazine, pyrrole and the like. Pharmaceutically acceptable salts forming part of this invention include salts derived from inorganic bases such as Li, Na, K, Ca, Mg, Fe, Cu, Zn, Mn; salts of organic bases such as N,N'-diacetylethylenediamine, betaine, caffeine, 2-diethylaminoethanol, 2- dimethylaminoethanol, N-ethylmorpholine, N-ethylpiperidine, glucamine, glucosamine, hydrabamine, isopropylamine, methylglucamine, morpholine, piperazine, piperidine, procaine, purines, theobromine, triethylamine, trimethylamine, tripropylamine, tromethamine, diethanolamine, meglumine, ethylenediamine, N,N'-diphenylethylenediamine, N,N'-dibenzylethylenediamine, N-benzyl phenylethylamine, choline, choline hydroxide, dicyclohexylamine, metformin, benzylamine, phenylethylamine, dialkylamine, trialkylamine, thiamine, aminopyrimidine, aminopyridine, purine, spermidine, and the like; chiral bases like alkylphenylamine, glycinol, phenyl glycinol and the like, salts of natural amino acids such as glycine, alanine, valine, leucine, isoleucine, norleucine, tyrosine, cystine, cysteine, methionine, proline, hydroxy proline, histidine, ornithine, lysine, arginine, serine, threonine, phenylalanine; unnatural amino acids such as D-isomers or substituted amino acids; guanidine, substituted guanidine wherein the substituents are selected from nitro, amino, alkyl, alkenyl, alkynyl, ammonium or substituted ammonium salts and aluminum salts. Salts may include acid addition salts where appropriate which are, sulphates, nitrates, phosphates, perchlorates, borates, halides, acetates, tartrates, maleates, citrates, succinates, palmoates, methanesulphonates, benzoates, salicylates, hydroxynaphthoates, benzenesulfonates, ascorbates, glycerophosphates, ketoglutarates and the like. Pharmaceutically acceptable solvates may be hydrates or comprising other solvents of crystallization such as alcohols. Particularly useful compounds according to this invention include: (5R)-3-[3-fluoro-4-(2 -oxo-l,3-oxazolan-3-yl)phenyl]-5-hydroxymethyI-l,3-oxazolan-2-one or its salts; (5R)043-fluoro-4-(24hioxo-l,3-oxa2olan-3-yl)phenyl]-5-hydroxymethyl-.13-oxazolan-2-one or its salts; (5R)-3-[3-fluoro-4-(24hioxo-l,3-thiazolan-3-yl)phenyl]-5-hydroxyrnethyl4,3-oxazolan-2-one or its salts; (5R)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-5-hydroxymethyl-l,3-oxazolan-2-one or its salts; 3-{2-fluoro-4-[(5R)-5-hydroxymethyl-2-oxo-l,3-oxazolan-3-yl]phenyl}-2,3-dihydrobenzo [d][l,3]oxazol-2-one or its salts; 3-{2-fluoro-4-[(5R)-5-hydroxymethyl-2-oxo-l,3-oxazolan-3-yl]phenyl}-6-rnethyl-2,3-dihydrobenzo[d][l,3]oxazol-2-one or its salts; 3-{2-fluoro-4-[(5R)-5-hydroxymethyl-2-oxo-l,3-oxazolan-3-yl]phenyl}-5-methyl-2,3-dihydrobenzo[d][l,3]oxazol-2-one or its salts; (5R)-5-hydroxyrnethyl-3-[4-(2-oxo-13-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-2-one or its salts; (5R)-3-[2-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-hydroxymethyl-l,3-oxazolan-2-one or its salts; (5R)-3-[3,5-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-hydroxymethyl-l,3-oxazolan-2-one or its salts; (5R)-5-hydroxymethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; 3-{4-[(5R)-5-hydroxymethyl-2-oxo-l,3-oxazolan-3-yl]phenyl}-2,3-dihydrobenzo[d][l,3] oxazol-2-one or its salts; (5R)-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-5-hydroxymethyl-l,3-oxazolan- 2-one or its salts; (5R)-3-{3-fluoro-4-[3-(4-methoxybenzyl)-4-oxo-l-imidazolidinyl]phenyl}-5-hydroxymethyl- l,3-oxazolan-2-one or its salts; (5R)-3-[3-fluoro-4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-5-hydroxymethyl-l,3-oxazolan- 2-one or its salts; (5R)-5-hydroxymethylO-[4-(3-niethyl-2-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-3-[3-fluoro-4-(2-oxo-3-phenyl-l-imidazolidinyl)phenyl]-5-hydroxymethyl-l,3-oxazolan 2-one or its salts; (5R)-3-{3-fluoro-4-[3-(fluorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-5-hydroxymethyl-13-oxazolan-2-one or its salts; (5R)-azidomethyl-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-azidomethyl-3-[3-fluoro-4-(3-methyl"2-thioxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2- one or its salts; 3-{4-[(5R)-5-azidomethyl-2-oxo-l,3-oxazolan-3-yl]-2-fluorophenyl}-6-methyl-2,3-dihydro benzo[d][l,3]oxazol-2-one or its salts; 3-{4-[(5R)-5-azidomethyl-2-oxo-l,3-oxazolan-3-yl]-2-fluorophenyl}-5-methyl-2,3-dihydro benzo[d][l,3]oxazol-2-one or its salts; (5R)-5-azidomethyl-3-[4-(2-oxo-l,3-Oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-2- one or its salts; (5R)-5-azidomethyl-3-[2-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-azidomethyl-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-5-azidomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; 3-{4-[(5R)-5-azidomethyl-2-oxo-l,3-oxazolan-3-yl]phenyl}-2,3-dihydrobenzo[d][l,3]oxazol- 2-one or its salts; (5R)-5-azidomethyl-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2- one or its salts; (5R)-5-azidomethyl-3-[3-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2- one or its salts; (5R)-5-a2idomethyl-3-{3-fluoro-4-[3-(4-fluorobenzyl)-2-oxo-l-imidazolidinyl]phenyl}-l,3-oxazolan-2-one or its salts; (5R)-aminomethyl-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-aminomethyl-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2- one or its salts; (5R)-5-aminomethylO-[4-(2-oxo-13-oxazolan-3-yl)-3-trifluoromethylphenyl]-1,3-oxazolan-2-one or its salts; (5R)-5-aminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-5-aminomethylO-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-5-aminomethyl-3-[3-fIuoro-4-(3-benzyl-4-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2-one or its salts; N-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methanamide or its salts; N-{(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-yimethyl} methanamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-0X0-1,3-oxazolan-5-ylmethyl} propanamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} butanamide or its salts; N1 - {(5S)-3-[3-fluoro-4-(2-oxo-1,3-oxazolan-3-yl)phenyl]-2-oxo-1,3-oxazolan-5-ylmethyl} pentanamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} heptanamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acrylamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}- 2,2,2-trifluoroacetamide or its salts; Ethyl(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl carbamoylmethanoate or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-thioxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-thioxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-2-oxo-3-[4-(24hioxo-l,34hiazolan-3-yl)phenyl]-l,3-oxazolan-5-ylmethy} acetamide or its salts; Nl-{(5S)-343-fluoro-4-(3-methyl-24hioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(6-methyl-2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}acetamide or its salts; Nl-.{(5S)-3-[3-fluoro-4-(5-methyl-2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}acetamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-5-ylmethyl}propanamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-5-ylmethyl}heptanamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-5-ylmethyl}acrylamide or its salts; Nl-{(5S)-3-[2-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} propanamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-5-ylmethyl}acetamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-l,3-oxazolan-5- ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5- ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-benzyl-4-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}acetamide or its salts; Nl-{(5S)-3-[4-(3-methyl-2-oxo-l-imidazolidinyl)phenyI]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[4-(3-benzyl-2-oxo-l-imidazolidinyl)phenyl]-2-0X0-1,3-oxazolan-5-yl-methyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl -((5S)-3- {3-fluoro-4-[3-(4-fluorophenyl)-2-oxo-l -imidazolidinyl]phenyl} -2-oxo-1,3-oxazolan-5-ylmethyl)acetamide or its salts; (5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyI]-5-(l-thioxoethylaminomethyl)-l,3-oxazolan-2-one or its salts; (5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-(3,3,3-trifluoro-l-thioxopropyl aminomethyl)-l,3-oxazolan-2-one or its salts; (5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-5-(l-thioxoethylamino methyl)-l,3-oxazolan-2-one or its salts; 3-{2-fluoro-4-[(5S)-2-oxo-5-(l-thioxoethylaminomethyl)-l,3-oxazoIan-3-yl]phenyl}-2,3-dihydrobenzo[d][l,3]oxazol-2-one or its salts; (5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-5-(l-thioxoethylamino methyl)-l,3-oxazolan-2-one or its salts; (5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-(l-thioxoethylamino methyl)-1,3-oxazolan-2-one or its salts; (5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-(l-thioxopropylamino methyl)-!,3- oxazolan-2-one or its salts; (5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-(l-thioxoethylaminomethyl)-l,3-oxazolan-2-one or its salts; (5S)-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-5-(l-thioxoethylamino methyl)- 1,3-oxazolan-2-one or its salts; (5S)-343-fluoro-4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-5-(l-thioxoethylamino methyl)-l,3-oxazolan-2-one or its salts; (5S)-343-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-5-(l-thioxoethylamino methyl)-l,3-oxazolan-2-one or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylcarbamate or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluorornethylphenyl]-l,3-oxazolan-5-ylmethyl} methylcarbamate or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylcarbamate or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methyl carbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methylcarbamate or its sats; (5S)-5-methylthioxy(thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-Oxazolan-3-yl) phenyl]-1,3-oxazolan-2-one or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-0X0-1,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methyldithiocarbamate or its sahs; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} ethylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} trifluoroacetoxythiocarbamate or its salts; (5S)-5-cyclohexyloxy (thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3- oxazolan-2-one or its sahs; Nl-{(5S)-3-[3-fluoro-4-(2-thioxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5- ylmethyl} ethylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}-l-propylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-hioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5- ylmethyl}-2-propylthiocarbamate or its salts; Nl - {(5S)-2-oxo-3-[4-(2-oxo-1,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-1,3-oxazolan-5- ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxa2olan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-5- ylmethyl}ethylthiocarbamate or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methyl thiocarbamate or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}ethyl thiocarbamate or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}-l-propyl thiocarbamate or its salts; (5S)-5-[2,2,2-trifluoroethyloxy(thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-l,3-oxazolan-2-one or its salts; (5S)-5-[2-methoxyethyloxy (thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-l,3-oxazolan-2-one or its salts; (5S)-5-[2-hydroxyethyloxy (thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-l,3-oxazolan-2-one or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}allylthio carbamate or its salts; Nl-{(5S)-3-[4-(2-oxO"l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}-2-propylthio carbamate or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-l,3-oxazolan-5- ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-2,3-dihydrobenzo[d][13]oxazol-3-yl)phenyl]-l,3-oxazolan-5-ylmethyl}ethylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-4-oxo-l-imida2olidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazoIan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(3-benzyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(3-benzyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} ethylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} ethylthiocarbamate or its salts; Nl-((5S)-3-{3-fluoro-4-[3-(4-fluorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-2-0X0-1,3-oxazolan-5-ylmethyl)methylthiocarbamate or its salts; Nl-((5S)-3-{3-fluoro-4-[3-(4-fluorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyl)ethylthiocarbamate or its salts; (5S)-5-[(2S)-2-hydroxymethylazolan-l-yl(thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-Oxazolan-2-one or its salts; (5S)-5-diethylamino(thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5S)-5-allylamino(thioxo)methylaminomethyI-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5S)-5-benzylamino(thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-1,3- oxazolan-2-one or its salts; (5S)-5-[4-methoxybenzylamino(thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxa2olan-2-one or its salts; (5S)- 3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-[2-pyridylmethylamino (thioxo)methyl aminomethyl]-1,3-oxazolan-2-one or its salts; (5S)-5-methyIamino (thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-1,3- oxazolan-2-one or its salts; (5S)-5-[2-hydroxyethylamino (thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-l,3-oxazolan-2-one or its salts; (5S).- 3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-[l,4-thiazinan-4-yl(thioxo)methylamino methyl]-l,3-oxazolan-2-one or its salts; (5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-[2-pyridylamino (thioxo)methylamino methyl]-1,3-oxazoIan-2-one or its salts; Nl-((-5S)-3-{3-fluoro-4-[3-(4-fluorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-2-0X0-1,3-oxazolan-5-ylmethyl)-2-propylthiocarbamate or its salts; (5S)-5-amino(thioxo)methylaminomethyl-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyi]-l,3-oxazolan-2-one or its salts; (5S)-3-[3-fluoro-4-(2-oxo-l,3-oxa2olan-3-yl)phenyl]-5-methylamino(thioxo)methylamino methyl-l,3-oxazolan-2-one or its salts; (5S)-5-amino(thioxo)methylaminomethyl-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts and (5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-methyIamino(thioxo)methyl aminomethyl-l,3-oxazolan-2-one or its salts. The present invention also relates to a process for the preparation of the compound of formula (I) where R1 represents NHR4, wherein R4 represents hydrogen atom and all other symbols are as defined earlier, which comprises: (i) reacting a compound of formula (III) where all the symbols are as defined earlier, with a compound of formula (IV) where L represents a leaving group such as halogen atom, alkoxy, sulfonyl groups and the like; R2 and R3 are as defined earlier, to produce a compound of formula (V) where Y1 Y2 Y3 R2 R3 and Z are as defined earlier, (ii) reducing the compound of formula (V) to produce a compound of formula (VI) where Y1 Y2, Y3 R2, R3 and Z are as defined earlier, (iii) reacting the compound of formula (VI) with alkylchloroformate, to produce a compound of formula (VII) where Rc represents methyl, ethyl, propyl, benzyl, allyl group and the like; Y1 Y2, Y3, R2, R3 and Z are as defined earlier, (iv) reacting the compound of formula (VII) with a compound of formula (VIII) where R12 represents a (C1-C3)alkyl group such as methyl, ethyl or propyl in the presence of a base to produce a compound of formula (I) where R represents hydroxy; Y1, Y2, Y3, R2, R3 and Z are as defined earlier, (v) reacting the compound of formula (I) with alkylsulfonyl chloride or aryl sulfonyl chloride to produce a compound of formula (I), where R1 represents alkyl sulfonyl or aryl sulfonyl, which in turn was reacted with NaN3 to produce compound of formula (IX) where Y1, Y2, Y3 R2 R3 and Z are as defined earlier, the compound of formula (IX) represents a compound of fomula (I) when R1 represents azido group and all other symbols are as defined earlier, and (vi) reducing the compound of formula (IX) to produce compound .of formula (X) where Y1, Y2, Y3 R2, R3 and Z are as defined earher, the compound of formula (X) represents a compound of fomula (I) when R1 represents NHR4, wherein R4 represents amino group and all other symbols are as defined earlier. The reaction of a compound of formula (III) with a compound of fomiula (IV) to produce a compound of formula (V) may be carried out using a base such as KOH. NaOH. K-2CO3, Na2C03, NaH, KH, triethylamine, diisopropylethyl amine and the like. The reaction may be carried out using a solvent such as DMSO, DMF, THF, acetonitrile, chlorofomi and the like or mixtures thereof The reaction may be carried out in inert atmosphere, which may be maintained using inert gases such as N2 or Ar. The reaction may be carried out at a temperature in the range of 20 °C-100 °C, preferably at a temperature in the range of ambient-80 °C. The reaction time may range from 1 to 15 h, preferably from 6 to 12 h. The reduction of a compound of formula (V) to produce a compound of formula (VI) may be carried out in the presence of gaseous hydrogen and a catalyst such as Ru. Pd, Rh, Pt, Ni on solid beads such as charcoal, alumina, asbestos and the like. The reduction may be conducted in the presence of solvents such as dioxane, acetic acid, ethyl acetate, THF, alcohol such as methanol, ethanol and the like or mixtures thereof A pressure between atmospheric pressure to 60 psi may be used. The reaction may be carried out at a temperature from 25 to 60 °C, preferably at room temperature. The reaction time ranges from 2 to 48 h. The reduction may also be carried out by employing metal in mineral acids such Sn/HCl, Fe/HCl, Zn/HCl, Zn/CH3CO2H and the like. The conversion of compound of formula (VI) to compound of formula (VI!) may be carried out with alkyIchloroformates such as methychloroformate, ethylchloroformate, propylchloroformate, benzylchloroformate and the like. The solvents of the reaction may be selected from water, acetone, tetrahydrofuran (THF), acetonitrile, dichloromethane (DCM) and the like or mixtures thereof The reaction may be carried out in the presence of base such as # K2CO3, Na2C03, NaH, KOH, triethylamine and the like. The temperature of the reaction may be carried out in the presence of 0 to 60 °C, preferably at 0 °C to room temperature. The time of the reaction is maintained in the range of l-12h, preferably in the range of l-4h. The reaction of a compound of formula (VII) with a compound of formula (VIII) to produce a compound of formula (I), where R represents hydroxy group, defined above may be carried out in the presence of a base such as alkali metal hydrides like NaH or KH or organolithiums like CH3Li, BuLi, LDA and the like or alkoxides such as NaOMe, NaOEt, t-BuOK. The reaction may be carried out in the presence of solvents such as THF, dioxane, DMF, DMSO, DME and the like or mixtures thereof HMPA may be used as a cosolvent. The reaction temperature may range from -78 to 150 °C, preferably at a temperature in the range of -78 to 30 °C. The duration of the reaction may range from 3 to 12 h. The compound of formula (I) where R1 represents OH is converted to compound of formula (I) where R1 represents alkylsulfonyl or arylsulfonyl by treating with alkylsulfonylchloride or arylsulfonylchloride such as methanesulfonyl chloride, p-toluenesulfonyl chloride and the like. The reaction may be carried out in the presence of chloroform, dichloromethane, THF, dioxane and the like or mixtures thereof The base used in the reaction may be selected from Et3N, diisopropyl ethylamine, NazCO3, K2CO3 and the like. The temperature of the reaction is maintained in the range of 0 to 50 °C, preferably in the range of 0 to room temperature. The time of the reaction should be maintained in the range of l-12h, preferably in the range of l-4h. The compound of formula (I) where R1 represents alkylsulfonylchloride or arylsulfonylchloride is converted to compound of formula (IX) by treating with NaN3. The solvents used in the reaction may be selected from dimethylformamide (DMF), dimethyl sulfoxide (DMSO), methylcyanide and the like. The tempearature of the reaction is maintained in the range of room temperature to 120 °C, preferably room temperature to 80°C. The time of the reaction is maintained in the range of l-12h, preferably l-4h. The reduction of a compound of formula (IX) to produce a compound of formula (X) may be carried out in the presence of gaseous hydrogen and a catalyst such as Ru, Pd, Rh. Pt. Ni on solid beads such as charcoal alumina, asbestos and the like. The reduction may be conducted in the presence of solvents such as dioxane, acetic acid, ethyl acetate, THF, alcohol such as methanol, ethanol and the like or mixtures thereof A pressure between atmospheric pressure to 60 psi may be used. The reaction may be carried out at a temperature from 25 to 60 °C, preferably at room temperature. The reaction time ranges from 2 to 48 h. The reduction may also be carried out by employing PPh3 in water. In still another embodiment of the present invention there is provided another process for the preparation of compound of formula (I) where R1 represents hydroxy and all the symbols are as defined earlier, which comprises: (i) reacting the compound of formula (VI) (ii) carbonylating the compound of formula (XII) with a suitable carbonylating agent to produce the compound of formula (I) where R1 represents hydroxy and all other symbols are as defined above. The reaction of a compound of formula (VI) defined above with a compound of formula (XI) defined above to produce a compound of formula (XII) may be carried out in the presence or absence of a base such as K2CO3, NaH, t-BuOK and the like or mixtures thereof The reaction may be carried out in the presence of solvents such as DMF, toluene, THF, CH3CN, and the like or mixtures thereof The reaction may also be carried out in the presence of Lewis acids such as BF3.0Et2, ZnCl2, Ti(0iPr)4, lanthanide metal complexes and the like in the presence of DCE, DMF, THF and the like or mixtures thereof The reaction temperature may be in the range of 0 to 120 °C, preferably at a temperature in the range of 0 to 100 °C. The reaction time may range from 3 to 24 h, preferably from 4 to 12 h. The conversion of compound of formula (XII) to a compound of formula (I) may be carried out using a carbonylating agent such as dialkyl carbonate, dihalo carbonyl, 1,1'-carbonyldiimidazole and the like in the presence or absence of a base. The base may be selected from triethylamine, tributylamine, diisopropylethylamine, DABCO, DBU, DBN, alkoxides like NaOMe, NaOEt and the like or the inorganic bases such as NaOH, KOH and the like. The reaction may be carried out in the presence of solvents such as dichloromethane, THF, DMF, ethyl acetate and the like or mixtures thereof The reaction temperature may be in the range of-20 to 135 °C, preferably at a temperature in the range of 15 to 80 °C. The reaction time may range from 2 to 72 h, preferably from 2 to 50 h. In still another embodiment of the present invention there is provided yet another process for the preparation of compound of the formula (I) where R1 represents azido and all other symbols are as defined earlier, which comprises: (i) reacting a compound of formula (VII) to produce a compound of formula (XIV) a compound of fomula (I) when R1 represents azido group and all other symbols are as defined earlier, The reaction of a compound of formula (VII) with a compound of formula (XIII) may be carried out in the presence of base such as NaH, KH, K2CO3, t-BuOK, LDA, NaOMe, with or without phase transfer catalyst such as tetrabutylammonium halide and the like. The reaction may be carried out in the presence of a suitable solvent such as THF, DMF, DMSO, benzene and the like or mixtures thereof The reaction may be carried out at a temperature in the range of-78 to 120 °C, preferably at -78 to 60 °C. The reaction time may range from 2 to 20 h, preferably from 4 to 10 h. The conversion of a compound of formula (XIV) to a compound of formula (XV) defined above may be carried in the presence of reagents such as I2, KI, or Nal. The reaction may be carried out in the presence of solvents such as CHCI3, CH2CI2, THF, DMF, DMSO, acetonitrile and the like or mixtures thereof The reaction temperature may be in the range of 0 to 100 °C, preferably at ambient temperature. The reaction time may range from 2 to 24 h. preferably from 2 to 12 h. The conversion of a compound of formula (XV) to a compound of formula (IX) may be carried out in the presence of one or more equivalents of metal azide such as LiN3, NaN3 or trialkyl silylazide. The reaction may be carried out in the presence of solvent such as THF. acetone, DMF, DMSO and the like or mixtures thereof The reaction may be carried out in inert atmosphere, which may be maintained using N2 or Ar. The reaction may be carried out at a temperature in the range of ambient temperature to reflux temperature of the solvent, preferably at a.temperature in the range of 50 to 80 °C. The reaction time may range from 0.5 to 18 h. preferably 1 to 4 h. In yet another embodiment of the present invention, there is provided a process for the preparation of compound of formula (I), where R1 represents hydroxy group and all other symbols are as defined earlier, which comprises: (ii) hydrolysing the acetonide moiety in the compound of fomiula (XVII) using conventional methods to produce a compound of formula (XVIII) where R1 represents hydroxy group and all other symbols are as defined earlier. The reaction of a compound of formula (VII) with a compound of formula (XVI) to produce a compound of formula (XVII) may be carried out in the presence of a base. The base employed may be selected from K2CO3, NaH, t-BuOK, LDA and the like. The reaction may be carried out in the presence of solvents such as DMF, THF, DMSO, EtOH and the like. The reaction may be carried at a temperature in the range of -78 to 120 °C, preferably at a temperature in the range of -78 to 100 °C. The reaction time may range from 2 to 24 h, preferably from 2 to 20 h. The hydrolysis of a compound of formula (XVII) to produce a compound of formula (XVIII) may be carried out using dilute mineral acid such as HCl, H2SO4 and the like, organic acids such as aqueous acetic acid, p-toluene sulfonic acid, camphorsulfonic acid, trifluoro acetic acid and the like. The reaction may be carried out in the presence of suitable solvent such as water, methanol, THF, dioxane and the like or mixtures thereof The reaction may be carried at a temperature in the range of 30 to 100 °C, preferably at a temperature in the range of 30 to 60 °C. The reaction time may range from 10 min to 5 h, preferably from 30 min to 2.5 h. The conversion of a compound of formula (XVIII) to a compound of formula (I) where R1 represents hydroxy group may be carried out using bases such as NaOMe, K2C03, NaH and the like, in presence of the solvents such as MeOH, DMF, THF, and the like. The duration and temperature of the reaction are maintained in the range of 2 to 4 h and room temperature to 150 °C respectively. In still another embodiment of the present invention there is provided a process for the preparation of compounds of formula (I) where R1 represents azido group and all other symbols are as defined earlier, which comprises: (i) reacting a compound of formula (VII) The reaction of a compound of formula (VII) defined above with a compound of formula (XIX) defined above may be carried out in the presence of a base such as NaH, NaOMe, K2CO3, n-BuLi, LDA and the like. The reaction may be carried out in the presence of solvents such as DMF, THF, DMSO, benzene and the like or mixtures thereof The reaction may be carried out at a temperature in the range of-78 to 70 °C preferably at a temperature in the range of-78 to 50 °C. The reaction time may range from 1 to 15 h preferably 1 to 10 h. The conversion of a compound of formula (XX) to a compound of formula (IX) may be carried out in the presence of one or more equivalent of metal azide such as LiN3, NaN3 or trialkyl silylazide. The reaction may be carried out in the presence of solvent such as THF, acetone, DMF, DMSO and the hke or mixtures thereof. The reaction may be carried out in inert atmosphere, which may be maintained using N2 or Ar. The reaction may be carried out at a temperature in the range of ambient temperature to reflux temperature of the solvent, preferably at a temperature in the range of 50 to 80 ^'C. The reaction time may range from 0.5 to 18 h, preferably 1 to 4 h. In still another embodiment of the present invention there is provided yet another process for the preparation of compound of the formula (I), where R1 represents NHR4, wherein R4 represents acetyl group and all other symbols are as defined earlier, which comprises: (i) reacting a compound of formula (VII) The compound of formula (VII) defined above may be converted to a compound of formula (I) defined above, by reacting with compound of formula (XXI) in presence of bases such as NaH, LDA, BuLi and the like. The reaction may be carried out at a temperature in the range of-78 to 100 °C, preferably in the range of-78 to 80°C. The reaction time may range from 3 to 10 h. In yet another embodiment of the present invention there is provided a process for the preparation of compound of formula (I), where R1 represents NHR4, wherein R4 represents formyl group; from compound of formula (X) where all symbols are as defined earlier. The reaction of compound of formula (X) to produce a compound of formula (I), where R1 represents NHR , wherein R represents formyl group, may be carried out in presence of alkyl formates such as methyl formate, ethyl formate and the like. The duration of the reaction may range from 4 to 48 h, prefereably 12 to 24 h. The reaction may be carried out at a temperature in the range of 60 to 120 °C preferably at reflux temperature. In another embodiment of the present invention there is provided a process for the preparation of compound of formula (I), where R1 represents NHR4, wherein R4 represents -C(=0)-R, R represesnts alkyl, alkoxy, alkenyl, haloalkyl or alkoxycarbonyl; from a compound of formula (X) where all symbols are as defined earlier. The compound of formula (I), where R1 represents NHR4, wherein R4 represents -C(-0)-R, R represents alkyl, alkoxy, alkenyl, haloalkyl or alkoxycarbonyl, may be prepared from compound of frmula (X) by treating with acyl halides. The reaction may be carrined out in the presence of solvents such as CH2CI2, CHCI3, toluene, THF and the like or mixtures thereof The reaction may be carried out in the presence of bases like EtjN, diisopropyl ethylamine, K2CO3, NaH, KOt-Bu and the like. The reaction may be earned at a temperature in the range of -20 to 60 °C, preferably at a temperature in the range of 0 to room temperature. The reaction time may range from 1 to 12 h, preferably from 1 to 4 h. Alternatively, the compound of formula (I), where R4 represents thioacyl group, may be prepared by reacting compound of formula (IX) with thioacetic acid. The compound of formula (IX) represents compound of formula (I) when R' represents azido group and all other symbols are as defined above. The compound of formula (IX) defined above may be converted to a compound of formula (I) defined above using thioacetic acid with or without using solvents such as THF, DMF, toluene and the like. The reaction may be carried out at a temperature in the range of 25 to 40° C, preferably at room temperature. The reaction may range from 3 to 24 h. preferably from 4 to 12 h. In another embodiment of the present invention there is provided a process for the preparation of compound of formula (I), where R1 represents NHR4, wherein R4 represents -C(=S)-R, R represents alkyl or haloalkyl; from compound of formula (I), where R' represents NHR4, wherein R4 represents -C(=0)-R, R represents alkyl or haloalkyl. where all symbols are as defined earlier. Conversion of compound of formula (I), where R1 represents NHR4. wherein R4 represents -C(=0)-R, R represents alkyl or haloalkyl, to a compound of fomula (I), where R1 represents NHR4, wherein R4 represents -C(=S)-R, R represents alkyl or haloalkyl. may be carried out by taking a solution of the amide and Lawesson's reagent in dry dioxane, toluene. THF, DMF and the like. The reaction may be carried at a temperature in the range of room temperature to 130 °C, preferably at a temperature in the range of 55 to 90 °C. The reaction time may range from 3 to 24 h, preferably from 3 to 10 h. In another embodiment of the present invention there is provided a process for the preparation of compound of formula (I), where R1 represents NHR4, wherein R4 represents -C(=S)-SMe, from compound of formula (X) where all symbols are as defined earlier. The compound of fomula (I), where R1 represents NHR4, wherein R4 represents -C(=S)-SMe, may be prepared from compound of formula (X), using CS2 in the presence of bases such as Et3N, diisopropyl ethylamine, K2CO3, NaH, KOt-Bu and the like. The reaction may be carried out in the presence of solvents such as water, ethanol, methanol, isopropanol CH3CN and the like, or mixtures thereof The reaction may be carried at a temperature in the range of room temperature to 60 °C, preferably at room temperature. The reaction time may range from 6 to 24 h. In another embodiment of the present invention there is provided a process for the preparation of compound of formula (I), where R1 represents NHR4, wherein R4 represents -C(=S)-OR, R represents alkyl, cycloalkyl, acyl, haloacyl, haloalkyl, hydroxyalkyl, alkoxyalky! or alkenyl, which comprises: where all symbols are as defined above. The compound of fomula (XXII) may be prepared from compound of formula (X) using thiophosgene, in the presence of bases such as Et3N, K2CO3, NaOH and the like. The reaction may be carried out in the presence of solvents such as ethanol, methanol, isopropanol, CH2Cl3-CH3CN and the like. The reaction may be carried at a temperature in the range of 0 to 60 °C. preferably at 0 °C. The reaction may be carried out in an inert atmosphere using argon or any other inert gas. The reaction time may range from 3 to 24 h. A compound of formula (I), where R1 represents NHR4, wherein R4 represents -C(=S)-OR, R represents alkyl, cycloalkyl, acyl, haloacyl, haloalkyl, hydroxyalkyl, alkoxyalkyl or alkenyl, is prepared from the compound of formula (XXII) in the respective alcohol in the presence of bases such as NaH, KH and the like The reaction may be carried out in the presence of solvents such as THF, toluene, DMF and the like. The reaction may be carried at a temperature in the range of room temperature to 130°C, preferably at reflux temperature of the solvent used. The reaction time may range from 6 to 24 h. In another embodiment of the present invention there is provided a process for the preparation of compound of formula (I), where R1 represents NHR4, wherein R4 represents -C(=S)-N(R):, R represents hydrogen, alkyl, alkenyl, substituted or unsubstituted aralkyl. heteroaralkyl, hydroxyalkyl or two R groups together form a 5 or 6 membered cyclic structures containing one or two hetero atoms; from a compound of formula (XXII) The compound of formula (I), where R1 represents NHR4, wherein R4 represents -C(=S)-N(R)2, R represents hydrogen, is prepared by passing ammonia gas into a solution of compound of formula (XXII) in the presence of solvents such as THF, toluene, and the like. The reaction may be carried at a temperature in the range of -10 °C to room temperature, preferably at -10 °C. The reaction time may range from 20 minutes to 4 h, preferably 30 minutes. The compound of formula (I), where R1 represents NHR4, wherein R4 represents -C(=S)-N(R)2, R represents alkyl, alkenyl, substituted or unsubstituted aralkyl, heteroaralkyl, hydroxyalkyl or two R groups together form a 5 or 6 membered cyclic structures containing one or two hetero atoms, is prepared by treating compound of formula (XXII) with appropriate amine in the presence of solvents such as THF, DMF, toluene, and the like. The reaction may be carried at a temperature in the range of room temperature to 140°C, preferably at 60 to 100 °C. The reaction time may range from 1 to 24 h, preferably 4 to 12 h. In still another embodiment of the present invention there is provided a novel intermediate of the formula (VII) wherein Rc represents methyl, ethyl, propyl, benzyl, allyl group and the like; R and R may be same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, haIo(C1-C6)alkyl, cyano, nitro, SR4a NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(CrC6)alkyl; Z represents S, O, =CH or NR^ where Rb represents hydrogen or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (Cr C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group; Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(CrC6)alkyl, (C1-C6)alkylsulfonyl, (CrC6)alkylcarbonylamino(Cr C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(CrC6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms. where Rc, Y1 Y2 Y3 R2 R3 and Z are as defined above, The reaction of a compound of formula (III) with a compound of formula (IV) to produce a compound of formula (V) may be carried out using a base such as KOH, NaOH, K2CO3, Na2C03, NaH, KH, triethylamine, diisopropylethyl amine and the like. The reaction may be carried out using a solvent such as DMSO, DMF, THF, acetonitrile, chloroform and the like or mixtures thereof The reaction may be carried out in inert atmosphere, which may be maintained using inert gases such as N2 or Ar. The reaction may be carried out at a temperature in the range of 20 °C-100 °C, preferably at a temperature in the range of ambient to 80 °C. The reaction time may range from 1 to 15 h, preferably from 6 to 12 h. The reduction of a compound of formula (V) to produce a compound of formula (VI) may be carried out in the presence of gaseous hydrogen and a catalyst such as Ru, Pd, Rh, Pt, Ni on solid beads such as charcoal, alumina, asbestos and the like. The reduction may be conducted in the presence of solvents such as dioxane, acetic acid, ethyl acetate, THF, alcohol such as methanol, ethanol and the like or mixtures thereof A pressure between atmospheric pressure to 60 psi may be used. The reaction may be carried out at a temperature from 25 to 60 °C, preferably at room temperature. The reaction time ranges from 2 to 48 h. The reduction may also be carried out by employing metal in mineral acids such Sn/HCl, Fe/HCl, Zn/HCl, Zn/CH3C02H and the like. The conversion of compound of formula (VI) to compound of formula (VII) may be carried out with alkylchloroformates such as methychloroformate, ethylchloroformate, propylchloroformate, benzylchloroformate and the like. The solvents of the reaction may be selected from water, acetone, tetrahydrofuran (THF), acetonitrile, dichloromethane (DCM) and the like or mixtures thereof The reaction may be carried out in the presence of base such as K2CO3, Na2C03, NAH, KOH, triethylamine and the like. The temperature of the reaction may be carried out in the presence of 0 to 60°C, preferably at 0 °C to room temperature. The time of the reaction is maintained in the range of l-12h, preferably in the range of l-4h. In still another embodiment of the present invention there is provided a novel intermediate of formula (VI) where R2 and R3 may be same or different and independently represent hydrogen, halogen atom, (CrC6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SR4 NRa ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, 0, ==CH or NRb where Rb represents hydrogen or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (CrC6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group; Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1 -C6)alkoxy(C1 -C6)alkyl, (C1 -C6)alkoxycarbonyl, carboxy(C1-C6)alky 1, (C i - C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; any two of Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms. where Y1, Y2 Y3 R2 R3 and Z are as defined earlier. The reaction of a compound of formula (III) with a compound of formula (IV) to produce a compound of formula (V) may be carried out using a base such as KOH, NaOH, K2CO3, Na2CO3, NaH, KH, triethylamine, diisopropylethyl amine and the like. The reaction may be carried out using a solvent such as DMSO, DMF, THF, acetonitrile, chloroform and the like or mixtures thereof. The reaction may be carried out in inert atmosphere, which may be maintained using inert gases such as N2 or Ar. The reaction may be carried out at a temperature in the range of 20 °C-lOO °C, preferably at a temperature in the range of ambient-80°C. The reaction time may range from 1 to 15 h, preferably from 6 to 12 h. The reduction of a compound of formula (V) to produce a compound of formula (VI) may be carried out in the presence of gaseous hydrogen and a catalyst such as Ru, Pd, Rh, Pt, Ni on solid beads such as charcoal, alumina, asbestos and the like. The reduction may be conducted in the presence of solvents such as dioxane, acetic acid, ethyl acetate, THF, alcohol such as methanol, ethanol and the like or mixtures thereof. A pressure between atmospheric pressure to 60 psi may be used. The reaction may be carried out at a temperature from 25 to 60 °C, preferably at room temperature. The reaction time ranges from 2 to 48 h. The reduction may also be carried out by employing metal in mineral acids such Sn/HCl, Fe/HCl, Zn/HCl, Zn/CH3CO2H and the like. In yet another embodiment of the present invention there is provided a novel intermediate of formula (XII) wherein R1 represents halo, azido, thioalcohol, OR4, NHR4 or. N(R4)2, where R4 represents hydrogen atom, or substituted or unsubstituted groups selected from acyl, thioacyl, (Ci- C6)alkoxycarbonyl, (C3-C6)cycloalkoxythiocarbonyl, (C2-C6)alkenyloxycarbonyl, (C2- C6)alkenylcarbonyl, aryloxycarbonyl, (C1-C6)alkoxythiocarbonyl, (C2- C6)alkenyloxythiocarbonyl, aryloxythiocarbonyl, -C(=0)-C(=0)-alkyl, -C(=0)-C(=0)"aryl, -C(=p)-C(=0)-alkoxy, -C(=0)-C(=0)-aryloxy, -(C=S)-S-alkyl, -(C=S)-NH2, -(C=S)-NH-alkyl, -C(=S)"N-(alkyl)2, -C(=S)-NH-alkenyl, (C=S)-(C=0)-alkoxy, -(C=S)-(C=0)-aryloxy, -C(=S)-0-(C=Q)-alkyl, C(=S)-C(=S)-alkyl, -C(=S)-C(=S)-aryl, -C(=S)-C(=S)-alkoxy, -C(=S)-C(=S)-aryloxy, S(0)2(C1-C6)alkyl, S(0)2aryl or thiomorpholinylthiocarbonyl; R2 and R3 may be same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C\-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NR where R represents hydrogen or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 or Y3 represents hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group or substituted or unsubstituted groups selected from (C]-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (Cr C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms. The novel intermediate of formula (XII) may be prepared by a process, which comprises: (i) reacting a compound of formula (III) where R1 represents NHR4 or N(R4)2, where R4 represents hydrogen atom, or substituted or unsubstituted groups selected from acyl, thioacyl, (C1-C6)alkoxycarbonyl, (C3- C6)cycloalkoxythiocarbonyl, (C2-C6)alkenyloxycarbonyl, (C2-C6)alkenylcarbonyl, aryloxycarbonyl, (C1-C6)alkoxythiocarbonyl, (C2-C6)alkenyIoxythiocarbonyl, aryloxythiocarbonyl, -C(=0)-C(=0)-alkyl, -C(=0)-C(=0)-aryl, -C(=0)-C(=0)-alkoxy, -C(=0)-C(=0)-aryloxy, -(C=S)-S-alkyl, -(C=S)-NH2, -(C=S)-NH-alkyl, -C(=S)-N-(alkyl)2, -C(=S)-NH-alkenyl, (C=S)-(C=0)-alkoxy, -(C=S)-(C=0)-aryloxy, -C(=S)-0-(C=0)-alkyl, C(=S)-C(-S)-alkyl, -C(=S)-C(-S)-aryl, -C(=S)-C(=S)-alkoxy, -C(=S)-C(=S)-aryloxy, S(0)2(C1-C6)alkyl, S(0)2aryl, thiomorpholinylthiocarbonyl or pyrrolidinylthiocarbonyl, to produce a compound of formula (XII) The reaction of a compound of formula (III) with a compound of formula (IV) to produce a compound of formula (V) may be carried out using a base such as KOH, NaOH, K2CO3, Na2COa, NaH, KH, triethylamine, diisopropylethyl amine and the like. The reaction may be carried out using a solvent such as DMSO, DMF, THF, acetonitrile, chloroform and the like/or mixtures thereof. The reaction may be carried out in inert atmosphere, which may be maintained using inert gases such as N2 or Ar. The reaction may be carried out at a temperature in the r^ge of 20 **C-100 °C, preferably at a temperature in the range of ambient to 80 °C. The reaction time may range from 1 to 15 h, preferably from 6 to 12 h. The reduction of a compound of formula (V) to produce a compound of formula (VI) may be carried out in the presence of gaseous hydrogen and a catalyst such as Ru, Pd, Rh, Pt, Ni on solid beads such as charcoal, alumina, asbestos and the like. The reduction may be conducted in the presence of solvents such as dioxane, acetic acid, ethyl acetate, THF, alcohol such as methanol, ethanol and the like or mixtures thereof. A pressure between atmospheric pressure to 60 psi may be used. The reaction may be carried out at a temperature from 25 to 60 °C, preferably at room temperature. The reaction time ranges from 2 to 48 h. The reduction may also be carried out by employing metal in mineral acids such Sn/HCl, Fe/HCl, Zn/HCl Zn/CH3C02H and the like. The reaction of a compound of formula (VI) defined above with a compound of formula (XI) defined above to produce a compound of formula (XII) may be carried out in the presence or absence of a base such as K2CO3, NaH, t-BuOK and the like or mixtures thereof The reaction may be carried out in the presence of solvents such as toluene, DMF, THF, CH3CN. The reaction may also be carried out in the presence of Lewis acids such as BF3.0Et2, ZnCl3, Ti(0iPr)4, lanthanide metal complexes and the like in the presence of DCE, DMF, THF and the like or mixtures thereof. The reaction temperature may be in the range of 0 to 120 °C, preferably at a temperature in the range of 0 to 100 °C. The reaction time may range from 3 to 24 h, preferably from 4 to 12 h. In yet another embodiment of the present invention there is provided a novel intermediate of formula (XVIII) where Rc represents methyl, ethyl, propyl, benzyl, allyl group and the like; R2 and R3 may be same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 or Y3 represents hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (Ci-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(Ci-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C i -C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y and Y when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms. where L represents a leaving group such as halogen atom, alkoxy, sulfonyl groups and the like; to produce a compound of formula (XVII) The reaction of a compound of formula (VII) with a compound of formula (XVI) to produce a compound of formula (XVII) may be carried out in the presence of a base. The base employed may be selected from K2CO3, NaH, t-BuOK, LDA and the like. The reaction may be carried out in the presence of solvents such as DMF, THF, DMSO, EtOH and the like. The reaction may be carried at a temperature in the range of -78 to 120 °C, preferably at a temperature in the range of -78 to 100 °C. The reaction time may range from 2 to 24 h, preferably from 2 to 20 h. The hydrolysis of a compound of formula (XVII) to produce a compound of formula (XVIII) may be carried out using dilute mineral acid such as HCl, H2SO4 and the like, organic acids such as aqueous acetic acid, p-toluene sulfonic acid, camphor sulfonic acid, trifluoro acetic acid and the like. The reaction may be carried out in the presence of suitable solvent such as water, methanol, THF, dioxane and the like or mixtures thereof The reaction may be carried at a temperature in the range of 30 to 100 °C, preferably at a temperature in the range of 30 to 60 °C. The reaction time may range from 10 min to 5 h, preferably from 30 min to 2.5 h. In yet another embodiment of the present invention there is provided a novel intermediate of formula (XX) f wherein Rc represents methyl, ethyl, propyl, benzyl, allyl group and the like; R2 and R3 may be same or different and independently represent hydrogen, halogen atom, '(C1-C6)alkyl group, halo(C1-C6)alkyI, cyano, nitro, SR2 NR2 OR2 where R2 represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y represents =0 or =S group and Y2 or Y3 represents hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1 -C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms. The novel intermediate of formula (XX) may be prepared by a process, which comprises: reacting a compound of formula (VII) The reaction of a compound of formula (VII) defined above with a compound of formula (XIX) defined above may be carried out in the presence of a base such as N2H. NaOMe, K2CO3, n-BuLi, LDA and the like. The reaction may be carried out in the presence of solvents such as DMF, THF, DMSO, benzene and the like or mixtures thereof The reaction may be carried out at a temperature in the range of-78 to 70 °C preferably at a temperature in the range of-78 to 50 °C. The reaction time may range from 1 to 15 h preferably 1 to 10 h. The enantiomers may be prepared by using reactants in their single enantiomeric form in the process wherever applicable or by conducting the reaction in the presence of reagents or catalysts in their single enantiomeric form. The single enantiomers may also be prepared by resolvnig the racemic mixture by conventional methods. The pharmaceutically acceptable salts are prepared by reacting the compounds of formula (I) wherever applicable with 1 to 4 equivalents of a base such as sodium hydroxide, sodium methoxide, sodium hydride, potassium t-butoxide, calcium hydroxide, magnesium hydroxide and the like, in solvents like ether, THF, methanol, t-butanol, dioxane, isopropanol. ethanol etc. Mixture of solvents may be used. Organic bases like lysine, arginine, diethanolamine, choline, tromethamine, guanidine and their derivatives etc. may also be used. Alternatively, acid addition salts wherever applicable are prepared by treatment with acids such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphoric acid, p-toluenesulphonic acid, methanesulfonic acid, acetic acid, citric acid, maleic acid salicylic acid. hydroxynaphthoic acid, ascorbic acid, palmitic acid, succinic acid, benzoic acid, benzenesulfonic acid, tartaric acid and the like in solvents like ethyl acetate, ether, alcoliols, acetone, THF, dioxane etc. Mixture of solvents may also be used. The salts of amino acid groups and other groups may be prepared by reacting the compounds of formula (I) with the respective groups in solvents like alcohols, ketones, ether etc. Mixture of solvents may be used. Various polymorphs of a compound of general formula (I) fomiing pan of this invention may be prepared by crystallization of compound of formula (I) under different conditions. For example, using different solvents commonly used or their mixtures for recrystallization; crystallizations at different temperatures; various modes of cooling, ranging from very fast to very slow cooling during crystallizations. Heating or melting the compound followed by gradual or fast cooling may also obtain polymorphs. The presence of polymorphs may be determined by solid probe nmr spectroscopy, IR spectroscopy, differential scanning calorimetry, powder X-ray diffraction or such other techniques. The present invention also provides pharmaceutical compositions, containing compounds of the general formula (I), as defined above, their derivatives, their analogs, their tautomeric forms, their stereoisomers, their polymorphs, their pharmaceutically acceptable salts or their pharmaceutically acceptable solvates in combination with the usual pharmaceutical ly employed earners, diluents and the like. The pharmaceutical compositions according to this invention can be used for the treatment of bacterial infections. They can also be used for the treatment of bacterial infections associated with multidrug resistance. Pharmaceutically acceptable solvates of compound of fonnula (I) forming parr of this invention may be prepared by conventional methods such as dissolving the compounds of formula (I) in solvents such as water, methanol, ethanol etc., preferably water and recrystallizing by using different crystallization techniques. The phamiaceutical compositions may be in the forms normally employed, such as tablets, capsules, powders, syrups, solutions, suspensions and the like, may contain tlavorants. sweeteners etc. in suitable solid or liquid carriers or diluents, or in suitable sterile media to form injectable solutions or suspensions. Such compositions typically contain from 1 to 20 %. preferably 1 to 10 % by weight of active compound, the remainder of the composition being pharmaceutically acceptable carriers, diluents or solvents. Suitable pharmaceutically acceptable carriers include solid fillers or diluents and sterile aqueous or organic solutions. The active compounds will be present in such pharmaceutical compositions in the amounts sufficient to provide the desired dosage in the range as described above. Thus, for oral administration, the compounds can be combined with a suitable solid, liquid carrier or diluent to form capsules, tablets, powders, syrups, solutions, suspensions and the like. The pharmaceutical compositions, may, if desired, contain additional components such as flavorants, sweeteners, excipients and the like. For parenteral administration, the compounds can be combined with sterile aqueous or organic media to form injectable solutions or suspensions. For example, solutions in sesame or peanut oil, aqueous propylene glycol and the like can be used, as well as aqueous solutions of water-soluble pharmaceutically-acceptable acid addition salts or salts with base of the compounds. The injectable solutions prepared in this manner can then be administered intravenously, intraperitoneally, subcutaneously. or intramuscularly, with intramuscular administration being preferred in humans. In addition to the compounds of formula (I) the pharmaceutical compositions of the present invention may also contain or be co-administered with one or more known drugs selected from other clinically useful antibacterial agents such as P-lactams or aminoglycosides. These may include penicillins such as oxacillin or flucloxacillin and carbapenems such as meropenem or imiphenem to broaden the therapeutic effectiveness against, for example. methicillin-resistant staphylococci. Compounds of the formula (I) of the present invention may also contain or be co-admistered with bactericidal/permeability-increasing protein product (BPI) or efflux pump inhibitors to improve activity against gram negative bacteria and bacteria resistant to antimicrobial agents. The compounds of the formula (I) as defined above are clinically administered to mammals, including human beings, via either oral or parenteral routes. Administration by the oral route is preferred, being more convenient and avoiding the possible pain and irritation of injection. However, in circumstances where the patient cannot swallow the medication, or absorption following oral administration is impaired, as by disease or other abnonnality, it is essential that the drug be administered parenterally. By either route, the dosage is in the range of about 5 mg/kg to about 20 mg / kg body weight of the subject per day administered singly or as a divided dose. However, the optimum dosage for the individual subject being treated will be determined by the person responsible for treatment, generally smaller doses being administered initially and thereafter increments made to determine the most suitable dosage. The invention is explained in detail in the examples given below which are provided b\ way of illustration only and therefore should not be construed to limit the scope of the invention. General procedure for preparing compounds 1-9: A mixture of appropriate nitro compound, 2-oxazolidinone (1.1 eq) and anhydrous K2CO3 (2.0 eq) in dry DMF was stirred at temperature ranging from 0 to 100 °C (depending on the substrate) overnight. Cold water was added to the reaction mixture and the solid formed was filtered. The filtered solids were dried to yield pure compound. Yield: 50-85%. r Preparation 10: Nl-(2-aminoethyl)-4-nitroaniline A solution of 4-fluoronitrobenzene (5 g, 35.4 mmol) in CH3CN (250 ml) was stirred at room temperature under argon overnight. The reaction mixture was filtered and the filtrate was concentrated. The residue obtained was suspended in pet. ether and filtered. The solids were collected to afford the nitro compound (4.1 g, 64 %) as yellow crystals. 1H NMR (DMSO+CDCI3, 200 MHz): 6 7.97 (d, J=9.3 Hz, 2H), 7.09 (bs, 1H), 6.62 (d, J=9.3 Hz, 2H), 2.80-3.40 (m, 6H). Mass(CI method): 181, 152,135,105. Preparation 11: l-(4-nitrophenyl)-2-imidazolidinone A solution of phosgene (20 % in toluene, 13 ml, 26.5 mmol) in toluene was added drop wise to a solution of the diamine (4 g, 22 mmol) and Et3N (7.6 ml, 55 mmol) in dichloromethane (100 ml) at 0 °C under argon. After being stirred at same temperature for 1 h, the reaction mixture was poured in water and extracted with dichloromethane (4x150 ml). The combined organic extracts were washed with water, brine and dried. The residue obtained upon evaporation of the solvents was passed through a column of silica gel to afford the product (3 g, 66 %) as yellow solid. ^H NMR (CDCI3, 200 MHz): 5 8.17 (d, J=9.3 Hz, 2H), 7.75 (d, J=9.2 Hz, 2H), 7,07 (bs, 1H), 4.00 (t, J=8.8 Hz, 2H), 3.59 (t, J=8.8 Hz, 2H). Mass(CI method): 207, 151, 105. Preparation 12: l-inethyl-3-(4-nitrophenyl)-2-imidazolidinone Sodium hydride (60 % in oil, 138 mg, 5.3 mmol) was added portion wise to a solution of the nitro compound (1 g, 4.8 mmol) in dry DMF (15 ml) under argon at 0 °C. Stirred the reaction mixture at the same temperature for 15 min. Methyl iodide (Mel) (0.68 g, 4.8 mmol) was added and the reaction mixture was stirred for 1 h. Ice pieces were added to the reaction mixture and the solid formed was filtered to afford the product (900 mg, 84 %) as yellow-crystals. 1H NMR (CDCI3, 200 MHz): 5 8.19 (d, J-9.3 Hz, 2H), 7.70 (d, J=9.3 Hz, 2H), 3.88 (t, J-8.8 Hz, 2H), 3.54 (t, J=8.8 Hz, 2H), 2.93 (s, 3H). Mass(CI method): 222. Preparation 13: l-(4-nitrophenyl)-4-iinidazolidinone A solution of 4-imidazohdinone (9.5 g, 110.5 mmol), 3,4-difluoro nitrobenzene (12.2 ml, 110.5 mmol) and diisopropyl ethylamine (28.6 ml, 165 mmol) in dry DMF (80 ml) was heated to 60 °C overnight under argon. The reaction mixture was allowed to cool to room temperature and ice pieces were added. The solid formed was filtered and washed with water. The solid was dried under air to yield the nitro compound (19.5 g, 78.5 %) as yellow crystals. 1H NMR (DMSO, 200 MHz): 5 8.81 (bs, 1H), 8.07-7.96 (m, 2H), 6.82 (t, J-8.8 Hz, 1H), 4.97 (s, 2H), 4.06 (s, 2H). Mass (CI method): 226, 185, 152. Preparation 14: Nl-phenyl-2-azidoacetainicle Chloroacetyl chloride (5.1 ml, 64.5 mmol) was added drop wise to a solution of aniline (5 g, 53.7 mmol) and Et3N (18,7 ml, 134.3 mmol) in dichloromethane (150 ml) at OX under argon. After the completion of reaction (TLC control), the reaction mixture was diluted with dichloromethane (300 ml). The resultant mixture was washed with water, brine and dried. The residue obtained upon evaporation of solvent was taken up in dry DMF (40 ml), added NaNs (6.r5 g, 94.6 mmol) and the resultant mixture was stirred at 80 °C for 2 h. The reaction mixture was diluted with ethyl acetate and washed with water, brine and dried. The residue obtained upon evaporation of the solvent was chromatographed over silica gel to afford the azide (6 g, 63%). Preparation 15: Nl-phenyl-2-(2-fluoro-4-nitroanilino)acetamide A solution of the azide (6 g, 34 mmol) obtained in preparation 14 was taken in MeOH (60 ml) and the resultant solution was hydrogenated over 10% Pd on charcoal (2.5 g) overnight. The reaction mixture was filtered on a celite pad and the filtrate was concentrated. To this residue dry DMF (40 ml) was added followed by diisopropyl ethyl amine (16.7 ml, 93.8 mmol) and 3,4-difluoronitro benzene (3.8 ml, 37.5 mmol). The resultant solution was kept at 80°C overnight with continuous monitoring by TLC. Ice-cold water was added to the reaction mixture and the solid separated was filtered to afford the nitro compound as a yellow solid (6 g, 61 %). 1H NMR (DMSO+CDCI3, 200 MHz): 5 9.74 (bs, 1H), 7.84-8.00 (m, 2H), 7.58 (d, J=8.3 Hz, 2H), 7.30 (d, J=8.3 Hz, 2H), 7.08 (m, 1H), 6.66 (t, J=8.8 Hz, 1H), 6.45 (bs, 1H), 4.09 (d, J=5.4 Hz, 2H). Mass (CI Method): 290. Preparation 16: Nl-(2-anilinoethyI)-2-fluoro-4-nitroaniline A 1 M solution of BH3.THF (45 ml, 45 mmol) was added drop wise to a solution of the nitro compound (4.5 g, 15.5 mmol) in dry THF (30 ml) at 0 °C under argon. The reaction mixture was stirred overnight at room temperature and then water was added cautiously to quench the excess borane. The volatiles were removed from the reaction mixture under vacuum and the residue was taken up in ethyl acetate (400 ml). The organic layer was washed with water, brine and dried. The residue obtained upon evaporation of the solvent was passed through column to afford the product (4 g, 93 %). 1H NMR (CDCI3, 200 MHz): 5 8.02-7.86 (m, 2H), 7.26-7.18 (m, 2H), 6.82-6.62 (m, 4H), 4.94 (bs, 1H), 3.83 (bs, 1H), 3.51 (s, 4H). Mass (CI method): 274. Preparation 17: l-(2-fluoro-4-nitrophenyl)-3-phenyl-2-imidazolidinone A solution of phosgene (20 % in toluene, 7.4 ml, 14.7 mmol) was added drop wise to a solution of the diamine (4 g, 14.5 mmol) and Et3N (5.6 ml, 40.4 mmol) in dichloromethane (50 ml) at 0 °C under argon. Stirred for 2 h at the same temperature the reaction mixture was diluted with dichloromethane (300 ml) and washed with water, brine and dried. The crystals obtained upon evaporation of the solvents were suspended in petroleum ether and filtered. The product was isolated as yellow crystals (4 g, 91.4 %). 1H NMR (CDCI3, 200 MHz): 5 8.10-7.11 (m, 8H), 4.22-4.00 (m, 4H). Mass (CI Melhod): 302, 106. Preparation 18: General procedure for the conversion of Ar=Substituted phenyl ring A solution of the nitro compound in THF was hydrogenated over 10% Pd on charcoal (catalytic amount) overnight. After the complete consumption of starting material, a 5% solution of Na2CO3 (2.2 eq) in water was added followed benzyl chloroformate (1.2 eq) at 0 °C After stirring the reaction mixture for 3 h at room temperature, it was filtered over celite bed and washed with ethyl acetate. The organic layer was separated from the filtrate and washed with water twice followed by brine. The organic extract was dried, evaporated and purified on a column of silica gel. Examples: A. General procedure for the conversion of To a solution of the starting material in dry THF at -78 °C under argon was added 1.6M BuLi (1.2 eq) drop wise. The reaction mixture was stirred for 45 min at the same temperature and then R-glycidyl butyrate (1.2 eq ) was added. Stirred for 1 h at -78 °C. Then the cold bath was removed while monitoring with TLC. After 3-12 h, the reaction mixture was quenched with saturated NH4CI solution and extracted with ethyl acetate. The combined organic extracts were washed with water, brine and dried. The residue obtained upon evaporation of solvents was chromatographed over silica gel to afford the product. To a solution of the alcohol, triethylamine (2.2 eq) in dry dichloromethane, methane sulfonylchloride (1.1 eq) was added at 0 °C under argon. The reaction mixture was warmed to room temperature over 2 h and then diluted with dichloromethane. The organic layer was washed with water, brine and dried. The residue obtained upon evaporation of the solvent was taken up in dry DMF and then NaN3 (1.5 eq) was added at room temperature. The resultant mixture was heated to 80 °C for 2-5 h while monitoring by TLC. Allowed the reaction mixture to attain room temperature, water was added and extracted with ethyl acetate. The combined organic extracts were washed with water (3 times), brine and dried. The residue obtained upon evaporation of the solvent was passed through column to obtain the azide. Where Ox=2-Oxazolidinone or its derivatives Ar=Substituted phenyl ring Procedure (i): A solution of the azide in THF: MeOH (1:3) was hydrogenated over 10% Pd on charcoal overnight. The reaction mixture was filered and the filtrate was concentrated. The residue was crystallized in MeOH to afford the amine. Procedure (ii): Triphenyl phosphine (1.3 eq) was added portion wise to a solution of the azide in dry THF and the resultant mixture was stirred at room temperature for 6 h. Water (few drops) was added and the reaction mixture was heated to 60 °C overnight. The solvent was evaporated and the residue was passed through a column of silica gel to afford the amine. Examples 32-37 have been prepared according to the general procedure C Where Ox=2-Oxazolidinone or its derivatives Ar=Substituted phenyl ring A solution of amine in methyl fomiate was heated to 80 °C overnight. The volatiles were removed under low pressure and the residue obtained was passed through column to yield formate in very pure form. Examples 38 & 39 have been prepared according to the general procedure C To a solution of the amine (1 eq) in dry dichloromethane at 0 °C under argon was added Et3N (2.5 eq) followed by respective acid chloride (1.2 eq) drop wise. After being stirred at room temperature for 1 to 6 h (TLC control), the reaction mixture was diluted with dichloromethane and washed with water twice followed by brine. The organic extract was dried, evaporated and was passed through column to afford the acylated product. Examples 40-70 have been prepared according to the general procedure E A solution of the amide (1 eq) and Lawesson's reagent (0.6 eq) in dry dioxane was heated to 55 to 90 "C over 3 to 10 h (TLC control). The reaction mixture was allowed to cool to room temperature and diluted with ethyl acetate. The resultant mixture was washed with water (4 times) followed by brine and dried. The residue obtained upon evaporation of solvent was passed through column of silica gel to afford the respective thioacetate. Examples 71-80 have been prepared according to the general procedure F To a solution of the amine (1 eq), Et3N (2.2 eq) in dry dichloromethane methyl chloroformate under argon was added at 0°'C (1.2 eq). The reaction mixture was stirred at room temperature overnight and worked up by diluting with dichloromethane followed by washing with water and brine. The residue obtained after evaporation of the dried organic layer was passed through column to afford the carbamate. To an ice cold mixture of amine (1 eq), Et2N (2 eq) and water (few drops) in EtOH CS2 (1 eq) was added under argon. Stirred overnight at room temperature, Methyl iodide (Mel) (1.1 eq) in EtOH was added and the stirring was continued for 12 h. The volatiles were removed and the residue was taken up in ethyl acetate. The organic mixture was washed with saturated NaHCO3, water, brine and dried. The residue obtained was passed through column to afford the product. Thiophosgene (1.2 eq) was added drop wise to a solution of the amine (1 eq), Et2N (2.4 eq) in dry dichloromethane at ice bath temperature under argon. The reaction mixture was warmed to room temperature over 3 h and then the volatiles were removed. The residue obtained was directly charged on to a column of silica gel to afford the product. Step (ii): A solution of the isothiocyanate in the respective alcohol was heated to 80 to 100 °C while monitoring by TLC. At the complete consumption of starting material, the reaction mixture was allowed to cool to room temperature. The crystals formed were separated, washed with ether and dried at vacuum to yield the pure product. Examples 88-120 have been prepared according to the general procedure I Ammonia gas was bubbled to a solution of isothiocyanate in THF at -10°C over 20 min. The resultant mixture was stirred at room temperature for 1 h and then diluted with ethyl acetate. The organic layer was washed with water (2 times), brine and dried. The residue obtained upon evaporation of the solvent was passed through a column of silica gel to afford the product. Examples 121-134 have been prepared according to the general procedure J In vitro Data: Minimum Inhibiton Concentrations (MICs) were determined by broth microdilution technique as per the guidelines prescribed om the fifth edition of Approved Standards, NCCLS document M7-A5 Vol 20 - No 2, 2000 Villinova, PA. Initial stock solution of the test compound was prepared in DMSO. Subsequent two fold dilutions were carried out in sterile Mueller Hinton Broth (Difco) (MHB). Frozen cultures stocks were inoculated into 50 ml sterile MHB in 250 ml Erlyn Meyer flasks. Composition of MHB is as follows: Beef Extract Powder - 2.0 g/litre Acid Digest of Casein - 17.5 g/ litre Soluble Starch - 1.5 g/litre Final pH 7.3 ±0.1 Flasks were incubated for 4 to 5 h at 35 °C on a rotary shaker at 150 rpm. Inoculum was prepared by diluting the culture in sterile MHB to obtain a turbidity of 0.5 McFarland standard. This corresponds to 1-2 x 108 CFU/ml. The stock was further diluted in sterile broth to obtain 1-2 X 106 CFU/ml. 50 JLII of the above diluted inoculum was added from 1-10 wells. The plates were incubated overnight at 37 °C. MIC is read as the lowest concentration of the compound that completely inhibits growth of the organism in the microdilution wells as detected by the unaided eye. ATCC: American Type Culture Collection, USA NCTC: National Collections of Type Cultures, Colindale, UK DRCC: Dr. Reddy's Culture Collection. The in vitro antibacterial activity data is shown in TABLE 1. TABLE 1: f In vitro Activity of Compounds against Gram positive and Gram negative bacteria wherein R1 represents halo, azido, thioalcohol, OR4, NHR4 or N(R4)2, where R4 represents hydrogen atom, or substituted or unsubstituted groups selected from acyl, thioacyl, (C1- C6)alkoxycarbonyl, (C3-C6)cycloalkoxythiocarbonyl, (C2-C6)alkenyloxycarbonyl, (C2- C6)alkenylcarbonyl, aryloxycarbonyl, (C1-C6)alkoxythiocarbonyl, (C2- C6)alkenyloxythiocarbonyl, aryloxythiocarbonyl, -C(=0)-C(=0)-alkyl, -C(=0)-C(=0)-aryl, - C(=0)-C(-0)-alkoxy, -C(=0)-C(=0)-aryloxy, -(OS)-S-alkyl, -(C=S)-NH2, -(C=S)-NH-alkyl, -C(=S)-N-(alkyl)2, -C(=S)-NH-alkenyl, (C=S)-(C=0)-alkoxy, -(C=S)-(C=0)-aryloxy, -C(=S)- 0-(C=0)-alkyl, C(=S)-C(=S)-alkyl, -C(=S)-C(=S)-aryl, -C(=S)-C(=S)-alkoxy, -C(=S)-C(=S)- aryloxy, S(0)2(C1-C6)alkyl, S(0)2aryl, thiomorpholinylthiocarbonyl or pyrrolidinylthiocarbonyl; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NR where R represents hydrogen, or substituted or unsubstituted (C1- C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1 - C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y and Y independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1- C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C 1 -C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C 1 -C6)alky 1, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates. 2. The compound according to claim 1, wherein the substituents on R4 are selected from halogen, hydroxy, amino, cyano, nitro, alkoxy, aryl, hydroxyaryl, pyridyl, hydroxyalkyl, alkoxyaryl or carboxyl and its derivatives. 3. The compound according to claim 1, wherein the substituents on Rb are selected from hydroxy, halogen, pyrrolidinylthiocarbonyl, nitro, amino, alkoxy, carboxy or cyano, 4. The compound according to claim 1, wherein the substituents on Y2 and Y3 are selected from hydroxy, nitro, cyano, amino, TBSO, halogen, alkyl, alkoxy, cycloalkyl, aryl, benzyloxy, acyl or acyloxy groups. 5. The compound according to claim 1, wherein the cyclic structure formed by Y2 and Y3 » is selected from substituted or unsubstituted benzene, pyridine, pyrrolidine, furan, thiophene, morpholine, piperazine or pyrrole. 6. A compound of the formula (I) as defined according to claim 1 which is selected from: (5R)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-hydroxymethyl-l,3-oxazolan-2-one or its salts; (5R)-3-[3-fluoro-4-(2-thioxo-l,3-oxazolan-3-yl)phenyl]-5-hydroxymethyl-l,3-oxazolan-2-one or its salts; (5R)-3-[3-fluoro-4-(2-thioxo-l,3-thiazolan-3-yl)phenyl]-5-hydroxymethyl-l,3-oxazolan-2-one or its salts; (5R)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-5-hydroxymethyl-l,3-oxazolan-2-one or its salts; 3-{2-fluoro-4-[(5R)-5-hydroxymethyl-2-oxo-l,3-oxazolan-3-yl]phenyl}-2,3-dihydrobenzo [d][l,3]oxazol-2-one or its salts; 3-{2-fluoro-4-[(5R)-5-hydroxymethyl-2-oxo-l,3-oxazolan-3-yl]phenyl}-6-methyl-2,3-dihydrobenzo[d][l,3]oxazol-2-one or its salts; 3-{2-fluoro-4-[(5R)-5-hydroxymethyl-2-oxo-l,3-oxazolan-3-yl]phenyl}-5-methyl-2,3-dihydrobenzo[d][l,3]oxazol-2-one or its salts; (5R)-5-hydroxymethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan- 2-one or its salts; (5R)-3-[2-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-hydroxymethyl-l,3-oxazolan-2-one or its salts; (5R)-3-[3,5-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-5-hydroxymethyl-1,3-oxazolan-2-one or its salts; (5R)-5-hydroxymethylO«[4-(2-oxo-13-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; 3- {4-[(5R)-5-hydroxymethyl-2-oxo-1,3-oxazolan-3-yl]phenyl} -2,3-dihydrobenzo[d] [ 1,3] oxazol-2-one or its salts; (5R)-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyi]-5-hydroxymethyl-l)3-oxazolan 2-one or its salts; (5R)-3-{3-fluoro-4-[3-(4-methoxybenzyl)-4-oxo-l-imidazolidinyl]phenyl}-5-hydroxymethyl- l,3-oxazolan-2-one or its salts; (5RV3-[3-fluoro-4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-5-hydroxymethyl-1,3-oxazolan- 2-one or its salts; (5R)-5-hydroxymethyl-3-[4-(3-methyl-2-oxo-1-imidazolidinyl)phenyl]-1,3-oxazolan-2-one or its salts; (5R)-3-[3-fluoro-4-(2-oxo-3-phenyl-l-imidazolidiny;)phenyl]-5-hydroxymethyl-1,3-oxazolan- 2-one or its salts; (5R)-3-{3-fluoro-4-[3-(fluorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-5-hydroxymethyl-l,3- oxazolan-2-one or its salts; (5R)-azidomethyl-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-azidomethyl-3-[3-fluoro-4-(3-methyl-2-thioxo-1-imidazolidinyl)phenyl]-1,3-oxazolan-2- one or its salts; 3-{4-[(5R)-5-azidomethyl-2-oxo-13-oxazolan-3-yl]-2-fluorophenyl}-6-methyl-23-dihydro benzo[d][l,3]oxazol-2-one or its salts; 3-{4-((5R)-5-azidomethyl-2-oxo-13-oxazolan-3-yl]-2-fluropheny;}-5-methyl-2,3-dihydro benzofd][l,3]oxazol-2-one or its salts; (5R)-5-azidomethyl-3-[4-(2-oxo4,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-13-oxazolan-2- one or its salts; (5R)-5-azidomethyl-3-[2-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l?3-oxazolan-2-one or its salts; (5R)-azidomethyl-3-[3,5-difluoro-4-(2-oxo-1,3-oxazolan-3-yl)phenyl]-1,3-oxazolan-2-one or its salts; (5R)-5-azidomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; 3-{4-[(5R)-5-azidomethyI-2-oxo-l,3-oxazolan-3-yl]phenyl}-2,3-dihdrobenzo[d][1,3]ozazol- 2-one or its salts; r (5R)-5-azidomethyl-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-5-azidomethyl-3-[3-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2- one or its salts; (5R)-5-azidomethyl-3-{3-fluoro-4-[3-(4-fluorobenzy)-2-oxo-1-imdazolidiny]phenyl}-1,3- oxazolan-2-one or its salts; (5R)-aminomethyl-3-[3-fluoro-4-(2-oxo«l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-aminomethyl-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-1,3-ozazolan-2- one or its salts; (5R)-5-aminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)-34rifluoromethylphenyl]-l,3-oxazolan-2- one or its salts; (5R)-5-aminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5R)-5-aminomethyl-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2- Dne or its salts; (5R)-5-aminomethyl-3-[3-fluoro-4-(3-benzyl-4-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2- one or its salts; N-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methanamide or its salts; N-{(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methanamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} propanamide or its salts; Nl-{(5S)-343-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} butanamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} pentanamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-1,3-oxazolan-5-ylmethy} heptanamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} aC1-ylamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}-2,2,2-trifluoroacetamide or its salts; Ethyl(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-13-oxazolan-5-ylmethyl carbamoylmethanoate or its salts; Nl-{(5S)-3-[3-fluoro-4-(24hioxo-13-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-thioxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-thioxo-13-thiazolan-3-yl)phenyl]-13-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(6-methyl-2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-2-oxo- l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4K5-methyl-2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-2-oxo- l,3-oxazolan-5-ylmethyl) acetamide or its salts; Nl - {(5S)-2-oxo-3-[4-(2-oxo-1,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-1,3-oxazolan-5- ylmethyl} acetamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-5- ylmethyl}propanamide or its salts; N1-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-5-ylmethyl} heptanamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-13-oxazolan-3-yl)-34rifluoromethylphenyl]-l,3-oxazolan-5-ylmethyl}aC1-ylamide or its salts; Nl-{(5S)-3-[2-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-1,3-oxazolan-5-ylmethy} acetamide or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-13-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} propanamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-lJ3-oxazolan-5-ylmethyl}acetamide or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-benzyl-4-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-{(5S)-3-[4-(3-benzyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-yl-methyl} acetamide or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} acetamide or its salts; Nl-((5S)-3-{3-fluoro-4-[3-(4-fluorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-2-oxo-1,3-oxazolan-5-ylmethyl)acetamide or its salts; (5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-(l-thioxoethylaminomethyl)-l,3-oxazolan-2-one or its salts; (5S)-3-[3-fluoro-4-(2-oxo-13-oxazolanO-yl)phenyl]-5-(3,3,3-trifluoro-l-thioxopropyl aminomethyl)-l,3-oxazolan-2-one or its salts; (5S)^-[3-fluoro-4-(3-methyl-2-thioxo-1-imidazolidiny)pheney]-5-(1-thioxoethylamino methyl)-1,3-oxazolan-2-one or its salts; 3-{2-fluoro-4-[(5S)-2-oxo-5-(l-thioxoethylaminomethyl)-l,3-oxazolan-3-yl]phenyl}-2,3-dihydrobenzo[d][l,3]oxazol-2-one or its salts; (5S)-3-[4-(2-oxo-13-oxazolan-3-yl)-3-trifluoromethylpheny]-5-(1-thioxoethylaminomethyl)- 1,3-oxazolan-2-one or its salts; (5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-(l-thioxoethylamino methyl)-1,3-oxazolan-2-one or its salts; (5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-(l-thioxopropylamino methyl)-1,3-oxazolan-2-one or its salts; (5S)-3-[4-(2-oxo-13-oxazolan-3-yl)phenyl]-5-(l-thioxoethylaminomethyl)-l,3-oxazolan-2-one or its salts; (5S)-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyi]-5-(l-thioxoethylamino methyl)-l,3-oxazolan-2-one or its salts; (5S)-3-[3-fluoro-4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-5-(l-thioxoethylamino methyl)-l,3-oxazolan-2-one or its salts; (5S)-3-[3-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-5-(l-thioxoethylamino methyl)-l,3-oxazolan-2-one or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylcarbamate or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-5-ylmethyl} methylcarbamate or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylcarbamate or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methyl carbamate or its salts; Nl-{(5S)-343-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5- ylmethyl} methylcarbamate or its salts; (5S)-5-methylthioxy (thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-1,3- oxazolan-2-one or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methyldithiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} ethylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-oxo-13-oxazolan-3-yl)phenyl]-2-oxo-13-oxazolan-5-ylmethyl} trifluoroacetoxythiocarbamate or its salts; (5S)-5-cyclohexyloxy (thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-1,3- * oxazolan-2-one or its salts; Nl-{(5S)-3-[3-fluoro-4-(2-thioxo-13-oxazolan-3-yl)phenyl]-2-oxo-13-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}ethylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5- ylmethyl}-l-propylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5- ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5- ylmethyl}-2-propylthiocarbamate or its salts; Nl - {(5S)-2-oxo-3-[4-(2-oxo-1,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-1,3-oxazolan-5- ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-l,3-oxazolan-5- ylmethyl}ethylthiocarbamate or its salts; Nl-{(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methyl thiocarbamate or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}ethyl thiocarbamate or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}-l -propyl thiocarbamate or its salts; (5S)-5-[2,2,2-trifluoroethyloxy(thioxo)methylam phenyl]-l,3-oxazolan-2-one or its salts; -(5S)-5-[2-methoxyethyloxy (thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-l,3-oxazolan-2-one or its salts; (5S)-5-[2-hydroxyethyloxy (thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-l,3-oxazolan-2-one or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}allylthio carbamate or its salts; Nl-{(5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}-2-propylthio carbamate or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-l,3-oxazolan-5-ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-2-oxo-3-[4-(2-oxo-2,3-dihydrobenzo[d][l,3]oxazol-3-yl)phenyl]-l,3-oxazolan-5-ylmethyl}ethylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(3-methyl-4-oxo-l-imidazolidinyl)phenyl]-2 -oxo-1,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(3-benzyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts; Nl-{(5S)-3-[4-(3-benzyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} ethylthiocarbamate or its salts; Nl-{(5S)-3-[3-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}methylthiocarbamate or its salts; Nl-{(5S)-343-fluoro-4-(3-phenyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}ethylthiocarbamate or its salts; Nl -((5S)-3- {3-fluoro-4-[3-(4-fluorophenyl)-2-oxo-1 -imidazolidinyl]phenyl} -2-oxo-1,3- oxazolan-5-ylmethyl)methylthiocarbamate or its salts; Nl-((5S)-3-{3-fluoro-4-[3-(4-fluoropte^ oxazolan-5-ylmethyl)ethylthiocarbamate or its salts; (5S)-5-[(2S)-2-hydroxymethylazolan-l^ oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5S)r5-diethylamino (thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-!,3- oxazolan-2-one or its salts; (5S)-5-allylamino (thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,3-oxazolan-2-one or its salts; (5S)-5-benzylamino(thioxo)methylaminomethyl-3-[4-)2-oxo-1,3-oxazolan-3-)phenyl]-1,3- oxazolan-2-one or its salts; (5S)-5-[4-methoxybenzylamino(thioxo)methylaminomethy]-3-[4-(2-oxo-1,3-oxazolan-3- yl)phenyl]-l,3-oxazolan-2-one or its salts; (5S)- 3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-[2-pyridylmethylamino (thioxo)methyl aminomethyl]-l,3-oxazolan-2-one or its salts; (5S)-5-methylamino (thioxo)methylaminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-l,3- oxazolan-2-one or its salts; (5S)-5-[2-hydroxyethylamino (thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-oxazolan-3-yl) phenyl]-l,3-oxazolan-2-one or its salts; (5S)- 3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-[l,4-thiazinan-4-yl (thioxo)methylamino methyl]-l,3-oxazolan-2-one or its salts; (5S)-3-[4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-[2-pyridylamino (thioxo)methylamino methyl]- l,3-oxazolan-2-one or its salts; Nl-((5S)-3-{3-fluoro-4-[3-(4-fluorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-2-oxo-l,3- oxazolan-5-ylmethyl)-2-propylthiocarbamate or its salts; (5S)-5-amino(thioxo)methylaminomethyl-3-[3-fluoro-4-(2-oxo-1,3-oxazolan-3-yl)phenyl]-1,3- oxazolan-2-one or its salts; (5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-5-methylamino(thioxo)methylamino methyl-l,3-oxazolan-2-one or its salts; (5S)-5-amino(thioxo)methylaminomethyl-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolan-3-y l,3-oxazolan-2-one or its salts and (5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolanO-yl)phenyl]-5-methylamino(thioxo)methyl aminomethyl-l,3-oxazolan-2-one or its salts. 7. A compound according to claims 1 and 6, wherein the pharmaceutically acceptable salt is selected from Li, Na, K, Ca, Mg, Fe, Cu, Zn, Mn; salts of organic bases such as N.V-diacetylethylenediamine, betaine, caffeine, 2-diethylaminoethanol, 2-dimethylaminoethanol. N-ethylmorpholine, N-ethylpiperidine, glucamine, glucosamine, hydrabamine, isopropylamine, methylglucamine, morpholine, piperazine, piperidine, procaine, purines, theobromine. triethylamine, trimethylamine, tripropylamine, tromethamine, diethanolamine, meglumine, ethylenediamine, N,N'-diphenylethylenediamine, N,N'-dibenzylethylenediamine, N-benzyl phenylethylamine, choline, choline hydroxide, dicyclohexylamine, metformin, benzylamme. phenylethylamine, dialkylamine, trialkylamine, thiamine, aminopyrimidine, aminopyridine, purine or spermidine; chiral bases like alkylphenylamine, glycinol or phenyl glycinol; salts of natural amino acids such as glycine, alanine, valine, leucine, isoleucine, norleucine, tyrosine, cystine, cysteine, methionine, proline, hydroxy proline, histidine, ornithine, lysine, arginine. serine, threonine, phenylalanine; unnatural amino acids such as D-isomers or substituted ammo acids; guanidine, substituted guanidine wherein the substituents are selected from nitro. amino, alkyl, alkenyl, alkynyl, ammonium or substituted ammonium salts and aluminum salts, salts may include acid addition salts where appropriate which are, sulphates, nitrates, phosphates. perchlorates, borates, halides, acetates, tartrates, maleates, citrates, succinates, palmoates. methanesulphonates, benzoates, salicylates, hydroxynaphthoates, benzenesulfonates. ascorbates, glycerophosphates or ketoglutarates. 8. A process for the preparation of the compound of formula (I) where R1 represents NHR4, wherein R4 represents hydrogen atom; R" and R- are same or different and independently represent hydrogen, halogen atom, (C1-C6))alkyl group, halo(C1- C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1- C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C\- C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C]-C6)alkoxycarbonyl or aryloxycarbonyl; Y represents =0 or =S group and Y and Y independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1- C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1i - C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1- 0 C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutical^ acceptable salts or its pharmaceutically acceptable solvates; which comprises: 3 (iii) reacting the compound of formula (VI) with alkylchloroformate, to produce a compound of formula (VII) 0 where Rc represents methyl, ethyl, propyl, benzyl or allyl group; Y1, Y2, Y3, R2, R3 and Z are as defined above, (iv) reacting the compound of formula (VII) with a compound of formula (VIII) (v) reacting the compound of formula (I) with alkylsulfonyl chloride or aryl sulfonyl chloride to produce a compound of formula (I), where R1 represents alkyl sulfonyl or aryl sulfonyl, which in turn was reacted with NaN3 to produce compound of formula (IX) a compound of fomula (I), when R1 represents azido group and all other symbols are as defined above, and (vi) reducing the compound of formula (IX) to produce compound of formula (X) where R represents hydroxy; R and R are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, 0, =CH or NR where R represents hydrogen, or substituted or unsubstituted (d- C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1i - C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or -S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1- C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alky 1, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1 C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates; which comprises: (i) reacting the compound of formula (VI) where R1 represents azido; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C\- C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1- C6)alkylcarbonyl, arylcarbonyl, (C]-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1- C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates; which comprises: (i) reacting a compound of formula (VII) where Rl represents azido group; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NR where R represents hydrogen, or substituted or unsubstituted (C\- C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1- C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1- C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbony1, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbbnyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates; which comprises: (i) reacting a compound of formula (VII) defined above, with a compound of formula (XIX) la a where R represents hydroxy group; R and R are same or different and independently represent hydrogen, halogen atom, (C1C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C|- C6)alkyl; Z represents S, 0, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1 C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, "12■% heterocyclyl or heterocycloalkyl; Y and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates; which comprises: (i) reacting a compound of formula (VII) (iii) cyclising the compound of formula (XVIII) with or without in presence of a base to a compound of formula (I), where R1 represents hydroxy group; Y1, Y2, Y3, R2, R3 and Z are as defined above. 13. A process for the preparation of compound of the formula (I) where Rl represents NHR4, wherein R4 represents acetyl group; R2 and R3 are same or different and, independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C]-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, ary 1, aralkyl, aryloxy, (C1-C6)alkylcarbony1, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1- C6)alky1, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1 - C6)alky lcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C r C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates; which comprises: (i) reacting a compound of formula (VII) where R1 represents NHR4, wherein R4 represents formyl group; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1- C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1- C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, 0, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1- C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y represents =0 -or =S group and Y and Y independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1- C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1- C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1- C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or where R4 represents NHR , wherein R represents -C(=0)-R, R represesnts alkyl, alkoxy. alkenyl, haloalkyl or alkoxycarbonyl; R and R are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa. NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(CV C1,)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl. aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl Y! represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano. nitro, formyl hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1,-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl. arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl (CV C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl. heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; which comprise: convening the compound of formula (X) whefe R1 represents NHR4, wherein R4 represents thioacyl group; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1- C6)alkyr, cyano, nitro, SRa, NR\ ORa where Ra represents substituted or unsubstituted (C1- C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, 0, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1- C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y represents =0 or =S group and Y and Y independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1- C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1- C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alky 1, (C1i - C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; which comprises: reacting compound of formula (IX) with thioacetic acid, where R1 represents NHR4, wherein R4 represents -C(=S)-R, R represents alkyl or haloalkyl; R~ and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1- C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1- C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C 1 -C6)alkyl, ary lcarbony lamino(C1-C6)alky 1, (C1 - C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; which comprises: convering the compound of formula (I) where R1 represents NHR4, wherein R4 represents -C(=S)-SMe; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (d-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1- * C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alky lsulfony1, (C1 - C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1- C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (d-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; which comprises: convering the compound of formula (X) where R1 represents NHR4, wherein R4 represents -C(=S)-OR, R represents alkyl, cycloalkyl, acyl, haloacyl, haloalkyl, hydroxyalkyl, alkoxyalkyl or alkenyl; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, 0Ra where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, 0, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1 C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, ' (C1-C6)alkylsulfonyl, (C1 C6)alky lcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alky 1, (C 1- C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1 C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; which comprises: (i) convering compound of formula (X) where R1 represents NHR4, wherein R4 represents -C(=S)-N(R)2, R represents hydrogen, alkyl, alkenyl, substituted or unsubstituted aralkyl, heteroaralkyl, hydroxyalkyl or two R groups together form a 5 or 6 membered cyclic structures containing one or two hetero atoms; R and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C]-C6)alkyl, cyano, nitro, SRa, NR\ ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, 0, -CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1 C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl (C1 C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl. (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl. (C1-.C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1 C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1 C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms; which comprises: converting compound of formula (XXII) where Rc represents R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, 0Ra where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(0-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents -0 or =S group and Y: and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0. =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1- C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1 -C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1 C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1 -C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y: and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms. 22. A process for the preparation of compound of formula (VII), claimed in claim 21 where R" and R/ may be same or different and independently represent hydrogen, halogen atom, (C1-Co)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NR\ ORa where Ru represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C\-C6)alkyl; Z represents S. O, =CH or NRh where Rh represents hydrogen or substituted or unsubstituted (C1-C6)Oalkyl, (C1-C6)alken\ 1. (C1-C6)cycloalkyl (C1-C6)alkoxy, aryi, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl. (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group; Y" and Y' independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino. =0. S group or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl. (C1-C6)alkoxy(C1-C6)alkyl (C1-C6)alkoxycarbonyl, carboxy(C1-C6))alkyl. [C1 C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino. (C1 C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y" and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, containing one or two hetero atoms. where R1 represents halo, azido, thioalcohol, OR4, NHR4 or N(R4)2, where R4 represents hydrogen atom, or substituted or unsubstituted groups selected from acyl, thioacyl, (C1- C6)alkoxycarbonyl, (C3-C6)cycloalkoxythiocarbonyl, (C2-C6)alkenyloxycarbonyl, (C2- C6)alkenylcarbonyl, aryloxycarbonyl, (C1-C6)alkoxythiocarbonyl, (C2- C6)alkenyloxythiocarbonyl, aryloxythiocarbonyl, -C(=0)-C(=0)-alkyl, -C(=0)-C( C(=0)-C(=0)-alkoxy, -C(=0)-C(=0)-aryloxy, -(C=S)-S-alkyl, -(C=S)-NH2, -(OS)-NH-alkyl, -C(=S)-N-(alkyl)2, -C(=S)-NH-alkenyl, (C=S)-(C=0)-alkoxy, -(OS)-(C=0)-aryloxy, -C(=S)- 0-(C=0)-alkyl, C(=S)-C(-S)-alkyl, -C(=S)-C(=S)-aryl, -C(=S)-C(=S)-alkoxy, -C(=S)-C(=S)- aryloxy, S(0)2(C1-C6)alkyl, S(0)2aryl, thiomorpholinylthiocarbonyl or pyrrolidinylthiocarbonyl; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, 0, =CH or NR where R represents hydrogen, or substituted or unsubstituted (C1- C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1 - C^alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y and Y independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, -S group, or substituted or unsubstituted groups selected from (C\- C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (CV C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y and Y when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms. 26. A process for the preparation of compound of formula (XII), claimed in claim 25 where Rc represents methyl, ethyl, propyl, benzyl or allyl group; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NR where R represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1- C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfony 1, (C1 - C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alky 1, (C1i - C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y2 and Y1 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms. where Rc represents methyl, ethyl, propyl, benzyl or allyl group; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1- C6)alkyl, cyano, nitro, SRa, NRa, ORa where Ra represents substituted or unsubstituted (C1- C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NRb where Rb represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1- C6)alkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y1 represents =0 or =S group and Y2 and Y3 independently represent hydrogen, halogen, cyano, nitro, formyl, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1- C6)alkyl, (C1-C6)alkoxycarbonyl, carboxy(C1-C6)alkyl, (C1-C6)alkylsulfonyl, (C1 - C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alky 1, (C1- C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, (C1-C6)alkylamino, arylamino, (d-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y: and Y3 when present on adjacent carbon atoms together may also form a substituted or unsubstituted 5 or 6 membered aromatic or non-aromatic cyclic structure, optionally containing one or two hetero atoms. as claimed in claim 1 and a pharmaceutically acceptable carrier, diluent, excipient or solvate. 32. A pharmaceutical composition as claimed in claim 31, in the form of a tablet, capsule, powder, syrup, solution or suspension. 33. A method of treating bacterial infections comprising administering a compound of formula (I) as claimed in claim 1 to a patient in need thereof. 34. A method of treating bacterial infections comprising administering a pharmaceutical composition as claimed in claims 31 and 32 to a patient in need thereof. 35. A pharmaceutical composition comprising a compound as claimed in claim 6 and a pharmaceutically acceptable carrier, diluent, excipient or solvate. 36. A pharmaceutical composition as claimed in claim 35, in the form of a tablet, capsule, powder, syrup, solution or suspension. 37. A method of treating bacterial infections comprising administering a compound as claimed in claim 6 to a patient in need thereof. 38. A method of treating bacterial infections comprising administering a pharmaceutical * composition as claimed in claims 35 and 36 to a patient in need thereof. |
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1124-mas-2000-claims filed.pdf
1124-mas-2000-claims grand.pdf
1124-mas-2000-correspondnece-others.pdf
1124-mas-2000-correspondnece-po.pdf
1124-mas-2000-description(complete) filed.pdf
1124-mas-2000-description(complete) grand.pdf
1124-mas-2000-description(provisional).pdf
1124-mas-2000-other documents.pdf
| Patent Number | 209017 | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Indian Patent Application Number | 1124/MAS/2000 | ||||||||
| PG Journal Number | 38/2007 | ||||||||
| Publication Date | 21-Sep-2007 | ||||||||
| Grant Date | 16-Aug-2007 | ||||||||
| Date of Filing | 26-Dec-2000 | ||||||||
| Name of Patentee | Dr. REDDY'S LABORATORIES LTD | ||||||||
| Applicant Address | 7-1-27 AMEERPET, HYDERABAD 500 016. | ||||||||
Inventors:
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| PCT International Classification Number | C 07 D 263/48 | ||||||||
| PCT International Application Number | N/A | ||||||||
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PCT Conventions:
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