Field of the Invention
The present invention relates to a process for the preparation of 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 process for the preparation of 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.
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, anti platelet 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 peniC1llin, 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 vancomyC1n, 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 inC1dence of the more virulent, methiC1llin-resistant Staphylococcus aureas (MRSA) among clinical isolates found worldwide. As with vancomyC1n resistant organisms, many MRSA strains are resistant to most of the

known antibiotics, but MRSA strains have remained sensitive to vancomyC1n. However, in view of the increasing reports of vancomyC1n 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 lincomyC1n 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, 0-phenyl, 0-C(=0)(C1-C6)alkyl, -0-C(=0)-phenyl (phenyl can be substituted with one to three F, C1, OCH3, OH, NH2, or (C,-C4)alkyl) or 0-C(=0)-0-CH3, S-(C1-C6)alkyl, S02-(C1-C6)alkyl, -S02-N(R^)2, (where R^ is independently hydrogen, (C1-C4)alkyl or phenyl which can be substituted with one to three F, C1, OCH3, OH, NH2, or (C1-C4)alkyl);
-C(=0)-(C,-C6)alkyl, -C(=0)-0-(CrC6)alkyl, -C(=0)-N(R1)2, -C(=0)-CH(R1)N(R1)2, -C(=0)-CH(R1')-NH-C(NH)-NH2 (where R* is an amino aC1d side chain); -N(R^)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 can be replaced with S, O or NR^), -C(CH3)=N-0R or Y represents any of the groups given below :


where R1 is OH, OCH3, CH2OH, CH2OCH3, CO2CH3, CO2C2H5, R1 represents CH3 or hydrogen, R^ represents CH2 or C(=0), R^ represents hydrogen or =0, p is 1 or 2, R*^ represents 0, S, S(0), SO2, CH2, NH, NCH3, NC2H5, NCHO, NCOCH3 or NCO2CH3, wherein each occurrence of said (C'i-C6)alkyl may be substituted with one or more F, C1, Br, I, OR1, COOR1, CN, SR1 or R1 (where R1 is a hydrogen or (C1-C4)alkyl); X and Z are independently (C1-C6)alkyl, (C3-C12)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-Cejalkyl, F, C1, Br, hydrogen or a (C1-C6)alkyl substituted with one or more of F, C1, 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, C1, 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 (lib)

(ii) International Patent Application WO 98/01447 discloses compound of formula (lie)

wherein R1 represents -NHC(=0)R^ wherein R^ represents (C|-C4)alkyl; R^ and R"* represent hydrogen or fluoro; R"* and R^ are independently hydrogen or methyl; R^ 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 S02amino, (C1-C4)alkanoylamino, carboxy, hydroxy, amino, (C1-C4)alkylamino, di-(C1-C4)alkylamino, (C1-C4)alkoxycarbonyl, carbamoyl, N-(C1-C4)alkylcarbamoyl, di-(N-(C1-C4)alkyl)carbamoyl (wherein the (C1-C4)alkyl group on groups in the last two mentioned carbamoyl groups is optionally substituted by hydroxy, (C1-C4)aIkoxy or (C1-C4)alkoxycarbonyl), (C2-C4)alkenyl (optionally substituted by carboxy or (C1-C4)alkoxycarbonyl), (C1-C4)alkoxy, cyano, or nitro
groups.
An example of this class of compounds is shown in formula (lid)


wherein X represents 0, S, SO, SO2, SNR1° or SONR"^; R represents hydrogen, (C1-Cgjalkyl optionally substituted with one or more of the following : F, C1, hydroxy, (C1-C8)alkoxy, (C1-C8)acyloxy or -0CH2Ph or R represents (C1-Cejcycloalkyl, amino, (C1-C8)alkylamino, (d-Cgjdialkylamino or (C1-C8)alkoxy; R1 represents hydrogen except when X is O, then R1 can be hydrogen, CH3, cyano, -CO2H, CO2R or (CH2)mR" (m is 1 or 2); R^ represents independently hydrogen, F or C1; R^ represents hydrogen or CH3; R1° independently represents hydrogen, (d-C4)alkyl (optionally substituted with chloro, fluoro, hydroxy, (C1-C8)alkoxy, amino, (C1-C8)alkylamino, or (C1-C8)dialkylamino) or p-toluenesulfonyl; R" represents hydrogen, hydroxy, OR, OCOR, NH2, NHCOR or N(R1°)2; and n is 0,1 or 2.


represents hydrogen atom, halogen atom, (C1-C8)alkyl, (C3-C6)cycloalkyl, -(CH2)m-0R" or -C(=0)-R1*'; X and Y are each and independently represents hydrogen atom, halogen atom; R"' and R^ are each and independently represents hydrogen atom, (C1-C8)alkyl, (C1-Cgjalkoxy, (C1-C8)aIkylthio, -(CH2)r„-0R^', -0-(CH2)n,-0R^', -NR1^R", -N=CH-NR1'R", -C(=0)-NR1'R1' or -(CH2)m-C(=A)-R^' or they may combine together to form =0, =NR^\ =S, =CR^^R1"* 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; R" and R1^ are each and independently represents hydrogen atom, (C1-C8)alkyl or methoxymethyl; R*' is hydrogen atom, -(CH2)ni-0H, (C1-C8)alkyl, (C1-C8)alkoxy, -O-CH2-O-C(=0)-R" or -(CH2)m-C(=0)-OR"; R"*^ and R^^ are each and independently represents hydrogen atom, -(CH2)m-0R", (CrC8)alkyl, -C(=0)-R1" -C(=0)-NR"R1^ -(CH2)p-phenyl. thiazoI-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-0H; R^^ is hydrogen atom, -OR^', (C1-C8)alkyl, (C,-C8)alkoxy, -{CH2)p-phenyl, NR^^R", -NH-C(=NH)-NH2, [l,2,4]triazol-4-yl or cyano; R^"* and R^^ are each and independently represents hydrogen atom, (C1-C8)alkyl, -C(=0)-R"" or -(CH2)p-phenyl; R^' is hydrogen atom, (C1-C8)alkyl substituted by one or more hydroxy; (C2-C8)alkenyl, (C1-C8)halogenalkyl, -(CH2)m-0R", -(CH2)m-C(=0)-R^', -C(=0)-(CH2)m-0R^ 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;



R1 is H or F, 0R\ SR1, NR^R^ CN, (C,-C4)alkoxycarbonyl, carboxamide, (C,-C4)acyl optionally substituted with one or more of the following : fluorine, hydroxy, (C1-C4)alkoxy, (C1-C4)acyloxy; NH0(C1-C6)alkyl or NH0CH2Ph, NSO2R where R is (C,-C6)alkyl optionally substituted with one or more F, C1, (C1-C6)alkoxy or phenyl; R^ is independently selected from hydrogen or fluorine, hydroxy, OR where R is (C1-C6)alkyl; (C1-C4)alkyl or Ph; R^ is independently selected from H, phenyl, pyridyl or (C1-C3)alkyl which can be optionally substituted with F, C1, hydroxy, (C1-C3)alkoxycarbonyl, (C1-C3)acyloxy, (C1-C3)alkoxy or N(CrC4 alkyl)2; R"* is independently H, OCH3, F or C1; R^ is hydrogen, (C1-C8)alkyl optionally substituted with one or more of the following : F, C1, hydroxy, (C1-C8)alkoxy, (C1-Cg)acyloxy; (C3-C6)cycloalkyl, amino, (C1-C8)alkylamino, (C1-C8)dialkylamino, (C1-C8)alkoxy; R^ is O, S. NR1^ CR"R1^ (0R)2, where R is (C,-C6)alkyl; 0(CH2)n, O, (SR)2 where R is (C1-Cejalkyi; S(CH2)mS; R^ is H, (C1-C8)alkyl optionally substituted with one or more of the following : F, C1, -CN, OH, (C1-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; (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, (C1-C3)alkoxy, (C1-C3)alkoxycarbonyl, (C1-C4)alkyl optionally substituted with one or more of F or (C1-C3) alkoxy; R^ and R^ are independently selected from H, (C1-Csjalkyl optionally substituted with one or more of the following : F, C1, -CN, OH, {C\-C8)alkoxy, (C1-C8)acyloxy, (C1-C8)alkoxycarbonyl, phenyl; (C1-Csjacyl optionally substituted with one or more of the following : hydroxy, (C1-C8)alkoxy, (C1-C8)acyloxy, amino, (C1-C4)acylamino, amino (C1-C4)acylamino; benzoyl optionally substituted with one or more of the following F, C1, hydroxy, (C1-C8)alkoxy, (C1-C8)acyloxy, amino, (C1-C4)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); R1° is H, OR^ NHR^ (C1-C8)alkyl optionally substituted with

phenyl; R" and R1^are independently selected from H, F, (C1-C4)alkyl optionally substituted with halogen, hydroxy, (C1-C4)alkoxy, (C1-C4)alkoxycarbonyl, phenyl; (C1-C8)acyl, (C1-C4)alkoxycarbonyl, CN; R1'^ is O or S; R1^ and R1^ 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; NR*R^ -0C(0) (C1-C4)alkyl; R^*^ is H. CHy, n is 0 or 1; m is,2 or 3;

R1 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; R^ and R1' are independently hydrogen or fluoro; R1* is hydrogen, methyl, ethyl or oxo; R^ is hydrogen, (C1-C6)alkyl, (C2-C6)alkenyl, (C2-C6)alkynyl, or of the formula R^(CH2)m wherein m is 1-4 and R* is trifluoromethyl, difluoromethyl, fluoromethyl, (d-C4)alkoxy, (C1-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^-(C|-C4)alkyl)ureido or of the formula -OC(=0)NR(R^) or N(R^)S02NR^(R^) wherein R^ and R* are independently hydrogen or (C1-C4)alkyl and R^ is (C1-C4)alkyl; or m is 2-4 and R^ is hydroxy, (C1-C4)alkanoylamino, amino, (C1-C4)alkylamino, (C1-C4)alkanesulphonamido, ureido, di-(N^-(C1-C4)alkyl)ureido or of the formula NHS02NR^(R*);


(vii) International Patent Application WO 98/01446 discloses compounds of formula (Ilm)

R1 is of the formula -NHC(=0)R1' wherein R1 is (C1-C4)alkyl; R1 and R^ are independently hydrogen or fluoro; R"* and R^ are independently hydrogen or methyl; R^ 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)alkyIamino, (C1-C4)alkoxycarbonyl, carbamoyl, N-(C1-C4)alkylcarbamoyl, -di-(N-{C1-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), (C1-C4)alkoxy, cyano or nitro; An example of this compound is shown in fig (Iln)

Summary of the Invention
Considering the tremendous upsurge as well as the need in this area of medical research, we initiated a-research program directed towards the discovery of novel antibacterial compounds effective against a number of human and veterinary pathogens, including gram-positive aerobic bacteria such as MRSA, streptococC1 and enterococC1 as well as anaerobic organisms such as Bacteroides spp, Clostridia spp. speC1es and aC1d-fast organisms such as Mycobacterium tuber-culosis, Mycobacterium avium and Mycobacterium spp. Accordingly, we have identified phenyl oxazolidinones as one of the several other pharmacophores we have conceived in our laboratory to design novel analogues which may have potential antibacterial

activity. 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 a process for the preparation of the new tricyclic oxazolidinones of the general formula (I) as defined above and their derivatives, their analogs, their tautomeric forms, their stereoisomers, their regioisomers, 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.

where R1 represents halo, azido, thioalcohol, isothiocyanate, OR1*, NHR1* or N(R1*)2, where R"*
represents hydrogen atom, or substituted or unsubstituted groups selected from acyl, thioacyl,
(C1-C6)alkoxycarbonyli cyclo(C3-C6)alkoxythiocarbonyl, (C2-C6)alkenyloxycarbonyl, (C?-
C6)alkenylcarbonyl, aryloxycarbonyl, (C1-C6)alkoxythiocarbonyI, (C2-
C6)alkenyloxythiocarbonyl, aryloxythiocarbonyl, -C(=0)-C(=0)- (C1-C6)alkyl, -C(=0)-C(=0)-aryl, -C(=0)-C(=0)- (C,-C6)alkoxy, -C(=0)-C(=0)-aryloxy, -(C=S)-S-(C,-C6)alkyl, -(C=S)-NH2, -(C=S)-NH-(CrC6)alkyl, -C(=S)-N-((C,-C6)alkyl)2, -C(=S)-NH-(C2-C6)alkenyl, (C=S)-(C=0)-(C!-C6)alkoxy, -(C=S)-(C=0)-aryloxy, -C(=S)-0-(C=0)- (C,-C6)alkyl, C(=S)-C(=S)-(C1-C6)alkyl, -C(=S)-C(=S)-aryl, thiomorpholinylthiocarbonyl or pyrrolidinylthiocarbonyl; R1 and R^ may be same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SR^ NR\ OR* where R* represents substituted or unsubstituted (C1-Cfi)alkyl group, or halo(C1-C6)aIkyl; Z represents S, O, =CH or NR*' where R1' 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, {Cr C6)alkoxycarbonyi or aryloxycarbonyl; Y' represents =0 or =S group and Y2 and Y independently represent hydrogen, halogen, cyano, nitro, hydroxy, amino, =0, =S group or

substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C,-
C6)alkoxy(C1-C6)aIkyl, (C1-C6)alkoxycarbonyl, (C1-C6)alkanoic aC1d, (C1-C6)alkylsulfonyL
(C1-C6)alkylcarbonylamino(C1-C6)aIkyl, arylcarbonylamino(C1-C6)alkyl, (C1-
C6)alkyIcarbonyloxy(C1-C6)aIkyl, amino(C1-C6)alkyl, mono(C1-C6)alkylamino, di(C,-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl. heterocyclyl or heterocycloalkyl; Y2 and Y2 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 R"* may be selected from hydrogen atom, (C1-C7)acyl 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; cyclo(C3-C6)alkoxythiocarbonyl group such as cyclopropoxythiocarbonyl, cyclobutoxythiocarbonyl and the like, the cyclo(C3-C6)alkoxythiocarbonyl 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 like, the aryloxycarbonyl group may be substituted; (C1-C6)alkoxythiocarbonyl group such as CH30-C(=S)-, C2H50-C(=S)- C3H70-C(=S)- and the like, 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 phenylO-C(=S)-, benzylO-C(=S)- and the like, which may be substituted; -C(=0)-C(=0)-(C1-C6)alkyl group such as -C(=0)-C(=0)methyl , -C(=0)-C(=0)ethyl, -C(=0)-C(=0)propyl and the like, which may be substituted; -C(=0)-C(=0)-aryl group such as -C(=0)-C(=0)phenyl, -

C(=0)-C(=0)naphthyl and the like, which may be substituted; -C(=0)-C(=0)-(C1-C6)alkoxy group such as -C(=0)-C(=0)methoxy, -C(=0)-C(=0)ethoxy, -C(=0)-C(=0)propyloxy and the like, which may be substituted; -C(=0)-C(=0)-aryIoxy group such as -C(=0)-C(=0)phenyloxy, -C(=0)-C(=0)benzyloxy, which may be substituted; -(C=S)-S-(C,-C6)alkyl such as -(C=S)-S-methyl, -(C=S)-S-ethyl, -(C=S)-S-propyl and the like, which may be substituted; -(C=S)-NH2; -(C=S)-NH-(C1-C5)alkyl such as -(C=S)-NH-methyl, -(C=S)-NH-ethyl, -(C=S)-NH-propyl and the like, which may be substituted; -C(=S)-N-((C1-C6)alkyl)2 such as -C(=S)-N-(methyl)2, -C(=S)-N-(ethyl)2, -C(=S)-N-(propyl)2 and the like, which may be substituted; -C(=S)-NH-(C2-C6)alkenyl such as -C(=S)-NH-ethenyl, -C(=S)-NH-propenyl, -C(=S)-NH-butenyl and the like, which may be substituted; -(C=S)-(C=0)-(C1-C6)alko;cy such as -(C=S)-(C=0)-methoxy, -(C=S)-(C=0)-ethoxy, -(C=S)-(C=0)-propoxy and the like, 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)-(C1-C6)alkyl such as -C(=S)-0-(C=0)-methyl, -C(=S)-0-(C=0)-ethyl, -C(=S)-0-(C=0)-propyl and the like, which may be substituted; -C(=S)-C(=S)-(C1-C6)alkyl group such as -C(=S)-C(=S)methyl, -C(=S)-C(=S)ethyl, -C(=S)-C(=S)propyl and the like, which may be substituted; -C(=S)-C(=S)aryl group such as -C(=S)-C(=S)phenyl, -C(=S)-C(=S)naphthyl and the like, which may be substituted; thiomorpholinylthiocarbonyl or pyrrolidinylthiocarbonyl.
When the groups represented by R1* are substituted, the substituents may be selected from halogen atom such as chlorine, fluorine, bromine and iodine; hydroxy, amino, mono(C1-C6)alkylamino such as methylamino, ethylamino, propylamino and the like, di(C1-C6)alkylamino such as dimethylamino, diethylamino, methylethylamino, dipropylamino, ethylpropylamino and the like, 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(Cr C6)alkyi 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^ OR^ where R^ represents substituted or unsubstituted (C1-C6)alkyl group such as methyl, ethyl.

propyl, isopropyl and the like; halo(C1-C6)alkyl such as halomethyl, haloethyl, halopropyl, haloisopropyl and the like, where the halo group is selected from fluro, chloro, bromo or iodo.
The substituents on R^ are selected from hydroxy, halogen, nitro, amino, alkoxy, carboxyl or cyano
Suitable groups represented by Z may be selected from S, O, =CH or MR*' 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; (C1-C6)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, ethylcafbonyl, propylcarbonyl and the like, which may be substimted; arylcarbonyl such as phenylcarbonyl, naphthylcarbonyl and the Uke, 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 R^ are selected from hydroxy, halogen, pyrrolidinylthiocarbonyl, nitro, amino, alkoxy, carboxyl or cyano.
Y' represents =0 or =S group, Y2 and Y2 are selected from hydrogen, halogen such as fluorine, chlorine, bromine or iodine; cyano, nitro, hydroxy, amino, =0, =S group, substituted or unsubstimted (C1-Cejalkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl and the like; hydroxy(C1-C6)alkyl such as hydroxymethyl, hydroxy ethyl, hydroxypropyl and the like, 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; (C1-C6)alkanoic aC1d such as CH3COOH, CH3CH2COOH, CH3(CH2)2COOH, CH3(CH2)3COOH 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(C1-C6)alkyl groups such as methylcarbonylaminomethyl, ethylcarbonylaminomethyl, methylcarbonylaminoethyl.

ethylcarbonylaminoethyl and the like, which may be substituted; arylcarbonylamino(C1-
C6)alkyl such as phenylcarbonylaminomethyl, phenylcarbonylaminoethyl,
naphtylcarbonylaminomethyl, naphthylcarbonylaminoethyl 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(C1-C6)alkyl such as aminomethyl, aminoethyl, aminopropyl and the like, which may be substituted; mono(C1-C6)alkylamino such as methylamino, ethylamino, propylamino and the like, which may be substituted; di(C1-C6)alkylamino sich as dimethylamino, diethylamino, methylethylamino, dipropylamino, ethylpropylamino 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, benzofliranyl 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 Y2 are substituted, the substituents may be selected from hydroxy, nitro, cyano, amino, (rert--butyldimethylsilyloxy) TBSO, halogen atom, (C1-C6)alkyl, (C1-C6)alkoxy, (C3-C6)cycloalkyl, aryl group such as phenyl, naphthyl and the like, benzyloxy, acyl group such as formyl, acetyl, and the like, carboxyl or acyloxy group such as formyloxy, acetyloxy and the like..
Suitable cyclic structure formed by Y2 and Y2 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 denved
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, glyC1nol, phenyl glyC1nol and the like, salts of natural amino aC1ds such as glyC1ne, alanine, valine, leuC1ne, isoleuC1ne, norleuC1ne, tyrosine, cystine, cysteine, methionine, proline, hydroxy proline, histidine, ornithine, lysine, arginine, serine, threonine, phenylalanine; unnatural amino aC1ds such as D-isomers or substituted amino aC1ds; guanidine, substituted guanidine wherein the substituents are selected from nitro, amino, alkyl such as methyl, ethyl, propyl and the like; alkenyl such as ethenyl, propenyl, butenyl and the like; alkynyl such as ethynyl, propynyl and the like; ammonium or substituted ammonium salts and aluminum salts. Salts may include aC1d addition salts where appropriate which are, sulphates, nitrates, phosphates, perchlorates, borates, hahdes, acetates, tartrates, maleates, C1trates, sucC1nates, 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.
Representative compounds prepared according to the process of the present invention
include: (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-imidazoIidinyl)phenyl]-5-hydroxymethyl-l,3-oxazolan-2-one or its salts;
3- {2-fluoro-4-[(5R)-5-hydroxymethyl-2-oxo-1,3-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-dihydroben2o[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-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-1,3-oxazolan-2-one or its salts; (5R)-3-[3-fluoro-4-(3-methyl-2-oxo-1-imidazolidinyl)phenyl]-5-hydroxymethyl-1,3-oxazolan-
2-one or its salts; (5R)-5-hydroxymethyI-3-[4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2-one or
its salts; (5R)-5-hydroxymethyl-3-[4-(3-benzyl-2-oxo-l-imidazolidinyl)phenyl]-l,3-oxazolan-2-one or
its salts;
(5R)-3-[3-fluoro-4-(2-oxo-3-phenyl-1-imidazolidinyl)phenyl]-5-hydroxymethyl-1,3-oxazolan-
2-one or its salts; (5R)-3-{3-fluoro-4-[3-(fIuorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-5-hydroxymethyl-l,3-
oxazolan-2-one or its salts;

(5R)-azidomethyl-3-[3-fluoro-4-(2-oxo-1,3-oxazolan-3-yl)phenyl]-1,3-oxazolan-2-one or its salts;
(5R)-azidomethyl-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyI)phenyI]-l,3-oxazolan-2-one or its salts;
3-{4-[(5R)-5-azidomethyI-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-oxa2olan-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-yI]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-azidomethyl-3-{3-fluoro-4-[3-(4-fluorophenyl)-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-aminomethyl-3-[4-(2-oxo-l,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-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-one or its salts;
(5R)-5-aminomethyl-3-[3-fluoro-4-(3-benzyl-4-oxo-l-imidazoIidinyl)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-oxazoIan-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-ylniethyl} 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-1,3-oxazolan-3-yl)phenyl]-2-oxo-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;
Nl-{(5S)-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,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-I,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-fluora-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; NI-{(5S)-2-oxo-3-[3-fluoro-4-(2-thioxo-l,3-thiazoIan-3-yl)phenyl]-l,3-oxazolan-5-y}methyl}
acetamide or its salts;

Nl-{(5S)-3-[3-fluoro-4-(3-methyl-2-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyljacetamide 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][ 1,3]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 -0X0-3 - [4-(2-oxo-1,3 -oxazolan-3 -yl)-3 -trifluoromethylphenyl] -1,3 -oxazo lan-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}heptananiide 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-1,3-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-ylinethyl} 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-ylmethyljacetamide or its salts;
Nl-{(5S)-3-[4-(3-methyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyll acetamide or its salts;
Nl-{(5S)-3-[4-(3-benzyl-2-oxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyU acetamide or its salts;
N1 - {(5 S)-3 -[3 -fIuoro-4-(3 -phenyl-2-oxo-1 -imidazolidinyl)phenyl] -2-oxo-1,3 -oxazolan-5 -ylmethyl} acetamide or its salts;
Nl-((5S)-3-{3-fluoro-4-[3-(4-fluorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-2-0X0-1,3-oxazolan-5-ylmethyl)acetamide or its salts;
(5S)-3-[3-fluoro-4-(2-0X0-1,3-oxazolan-3-yl)phenyl]-5-( 1 -thioxoethylaminomethyl)-1,3-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-oxazolan-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-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-thioxopropyIamino methyl)-1,3-
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)-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-oxa2oIan-5-ylmethyl} methyl
carbamate or its salts;
Nl-{(5S)-3-[3-fIuoro-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]-l,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-l,3-oxazolan-3-yl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl}
methylthiocarbamate or its salts;
Nl-{(5S)-3-[3-fluoro-4-(2-0X0-1,3-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]-1,3-
oxazolan-2-one or its salts;
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-
ybnethyl} 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-
yhnethyl}methylthiocarbamate or its salts;

Nl-{(5S)-3-[3-fIuoro-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-trifluoroniethylphenyl]-1,3-oxazolan-5-ylmethyl}methylthiocarbamate or its salts;
Nl - {(5S)-2-oxo-3-[4-(2-oxo-1,3-oxazolan-3-yl)-3-trifluoromethylphenyl]-1,3-oxazolan-5-ylmethyljethylthiocarbamate 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}ethy!
thiocarbamate or its salts;
Nl - {(5S)-3-[4-(2-oxo-1,3-oxazolan-3-yl)phenyl]-2-oxo-1,3-oxazolan-5-ylmethyl} -1 -propyl
thiocarbamate or its salts;
(5S)-5-[2,2,2-trifluorpethyloxy(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)methyiaminomethyl]-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;
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-oxazoIan-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-
ybnethyl}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-1 -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-1 -imidazolidinyl)phenyl]-2-oxo-1,3-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-imidazoHdinyl)phenyl]-2-oxo-l,3-oxa2olan-5-ylmethyl} ethylthiocarbamate or its salts;
Nl-((5S)-3-{3-fluoro-4-[3-(4-fluorophenyl)-2-oxo-l-imidazoiidinyl]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyl)methylthiocarbamate or its salts;
Nl-((5S)-3-{3-fluoro-4-[3-(4-f[uorophenyl)-2-oxo-l-imidazolidinyl]phenyl}-2-0X0-1,3-oxazolan-5-ylmethyl)ethylthiocarbamate 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;
Nl-((5S)-3-{3-fluoro-4-[3-methoxymethyl-4-oxo-l-imidazolidinyI]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyl)methylthiocarbamate or its salts;
Nl-((5S)-3-{3-fluoro-4-[3-benzyl-4-oxo-l-imidazolidinyl]phenyl}-2-0X0-1,3-oxazolan-5-ylmethyl)methylthiocarbamate or its salts;
Nl-((5S)-3-{3-fluoro-4-[3-benzyl-4-oxo-l-imidazolidinyl]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyl)ethylthiocar;bamate or its salts;
Nl-((5S)-3-{4-[4-oxo-l-imidazolidinyl]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyl)-(N,N-dimethylamino)ethylthiocarbamate or its salts;
Nl-((5S)-3-{3-fluoro-4-[3-(4-methoxybenzyl)-4-oxo-l-imidazolidinyl]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyl)methylthiocarbamate or its salts;

Nl-((5S)-3-{3-fluoro-4-[3-benzyl-4-oxo-l-imidazolidinyl]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyl)isopropylthiocarbamate or its salts;
Nl-((5S)-3-{3-fIuoro-4-[3-hydroxymethyl-4-oxo-l-imidazolidinyl]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyI)methylthiocarbamate or its salts;
Nl-((5S)-3-{3-fluoro-4-[4-oxo-l-imidazolidinyl]phenyl}-2-0X0-l,3-oxazolan-5-ylmethyl) methylthiocarbamate or its salts;
Nl-{(5S)-3-[3-fluoro-4-(3-methyl-4-thioxo-l-imidazolidinyl)phenyl]-2-oxo-l,3-oxazolan-5-ylmethyl} methylthiocarbamate or its salts;
(5S)-5-[(2S)-2-hydroxymethylazolan-l-yl(thioxo)methylaminomethyl]-3-[4-(2-oxo-l,3-
oxazoIan-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]-1,3-
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-l,3-oxazolan-3-yl)phenyl]-l,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-oxazolan-2-one or its salts;
(5S)- 3-[4-(2-0X0-1,3-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-bxazolan-3-yl)phenyl]-5-[2-pyridylamino (thioxo)methylamino methyl]-
l,3-oxazolan-2-one or its salts; (5S)-5-amino(thioxo)methylaniinomethyl-3-[3-fluoro-4-(2-oxo-l,3-oxazolan-3-yl)phenyl]-l,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)methylaininomethyl-3-[3,5-difluoro-4-(2-oxo-1,3-oxazolan-3-yl)phenyl]-1,3-oxazolan-2-one or its salts;
(5S)-3-[3,5-difluoro-4-(2-oxo-l,3-oxazolaii-3-yl)phenyl]-5-methylamino(thioxo)methyl aminomethyl-l,3-oxazolan-2-one or its salts and
Nl-((5S)-3-{4-[4-oxo-l-imidazolidinyl]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyl)-(N,N-dimethylamino)ethylthioearbamate.hydrochloride.

where R1 represents NHR1' wherein R"* represents hydrogen atom; Y', Y\ Y\ R^ R^ 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, 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, 1 -methyl-2-pyrrolidinone (NMP), acetamide, toluene, xylene and the like or mixtures thereof The reaction may be carried out in inert atmosphere, which may be maintained using inen gases such as N2, He or Ar. The reaction may be carried out at a temperature in the range of 20 to 180 "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, Ft, Ni on solid beads such as charcoal, alumina, asbestos and the like. The reduction may be conducted in the presence of a solvent such as dioxane, acetic aC1d, 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 in the range of 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 aC1ds such Sn/HCl, Fe/HCl, Zn/HCl, Zn/CHjCOiH 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 solvent 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 1 to 12 h, preferably in the range of 1 to 4 h.
The reaction of a compound of formula (VII) with a compound of formula (VIII) to produce a compound of formula (I), where R1 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 CH^Li, BuLi, LDA and the like or alkoxides such as NaOMe, NaOEt, t-BuOK. The reaction may be carried out in the presence of a solvent such as THF, dioxane, DMF, DMSO, DME and the like or mixtures thereof. Hexamethylphosphamide (HMPA) may be used as a co-solvent. 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, Na2C03, 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 1 to 12 h, preferably in the range of 1 to 4 h. The compound of formula (I) where R1 represents alkylsulfonyl or arylsulfonyl is converted to compound of formula (I) where R1 represents azido group, by treating with NaNj. The solvent used in the reaction may be selected from dimethylformamide (DMF), dimethyl sulfoxide (DMSO), acetamide and the like. The temperature of the reaction is maintained in the range of room temperature to 120 °C, preferably room temfJerature to 80 °C. The time of the reaction is maintained in the range of 1 to 12 h, preferably 1 to 4 h.
The reduction of a compound of formula (I) where R1 represents azido group, to produce a compound of formula (I) where R1 represents NHR1* wherein R"* represents hydrogen atom, may be carried out in the presence of gaseous hydrogen and a catalyst such as Ru, Pd, Rh, Ft, Ni on solid beads such as charcoal, alumina, asbestos and the like. The reduction may be conducted in the presence of a solvent such as dioxane, acetic aC1d, 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 in the range of 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 PPhj in water.


(ii) carbonylating the compound of formula (X) with a suitable carbonyiating 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 (IX) defined above to produce a compound of formula (X) 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 a solvent such as DMF, toluene, THF, CH3CN, and the like or mixtures thereof. The reaction may also be carried out in the presence of Lewis aC1ds such as BF3.0Et2, ZnCh, 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 firom 3 to 24 h, preferably from 4 to 12 h.
The conversion of compound of formula (X) 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 fi-om triethylamine, tributylamine, diisopropylethylamine, l,4-diazabicyclo[2.2.2]octane

(DABCO), l,8-diazabicyclo[5.4.0]undec-7-ene (DBU), l,l,5-diazabicyclo[4.3.0]non-5-ene (DBN), alkoxides like NaOMe, NaOEt and the like or the inorganic base such as NaOH, KOH and the like. The reaction may be carried out in the presence of a solvent 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.



The reaction of a compound of formula (VII) with a compound of formula (XI) 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 (XII) to a compound of formula (XIII) 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 a solvent such as CHC13, CH2C12, 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 (XIII) to a compound of formula (I) where R1 represents azido group, may be carried out in the presence of one or more equivalents of metal azide such as LiNa, NaNs 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, He 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:


The reaction of a compound of formula (VII) with a compound of formula (XIV) to produce a compound of formula (XV) 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 a solvent 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 (XV) to produce a compound of formula (XVI) may be carried out using dilute mineral aC1d such as HCl, H2SO4 and the like, organic aC1ds such as aqueous acetic aC1d, p-toluene sulfonic aC1d, camphorsulfonic aC1d, trifluoro acetic aC1d 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 (XVI) to a compound of formula (I) where R1 represents hydroxy group, may be carried out by using a base such as NaOMe, K2CO3, NaH and the like, in presence of the a solvent 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.



The reaction of a compound of formula (VII) defined above with a compound of formula (XVII) 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 a solvent 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 (XVIII) to a compound of formula (I) where R1 represents azido group, may be carried out in the presence of one or more equivalent of organic or an inorganic azide such as LiNa, 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 by using He, 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 firom 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 NHR1*, wherein R1* represents acetyl group and all other symbols are as defined earlier, which comprises: (i) reacting a compound of formula (VII)


where R1 represents NHR1', where R"* represents acetyl group; and Y', Y2 Y2 R^, R^ and Z are as defined eariier.
The compound of formula (VII) defined above may be converted to a compound of formula (I) defined above, by reacting with compound of formula (XIX) in presence of a base 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 fi-omSto 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 NHR"*, wherein R" represents formyl group; from compound of formula (I) where R1 represents NHR"* wherein R"* represents hydrogen atom,
where all other sjonbols are as defined earlier.
The reaction of compound of formula (I) where R1 represents NHR"* wherein R1' represents hydrogen atom, to produce a compound of formula (I), where R1 represents NHR", wherein R1* represents formyl group, may be carried out in presence of alkyl formates such as

methyl formate, ethyl formate, propyl 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 NHR1*, wherein R"* represents -C(=0)-R1*', where R^" represents (C1-C6)alkyl, (C1-C6)alkoxy, (C2-C6)alkenyl, halo(C,-C6)alkyl, aryloxy, (C2-C6)alkenyloxy, aryloxycarbonyl or (C1-C6)alkoxycarbonyl; from a compound of formula (I) where R1 represents NHR" wherein R"* represents hydrogen atom,

where all other symbols are as defined earlier.
The compound of formula (I), where R1 represents NHR"*, wherein R"* represents -C(=0)-R^', R^' represents (C1-C6)alkyl, (C1-C6)alkoxy, (C2-C6)alkenyl, halo(C,-C6)alkyl aryloxy, (C2-C6)alkenyloxy, aryloxycarbonyl or (C1-C6)alkoxycarbonyl, may be prepared from compound of formula (I) where R1 represents NHR1* wherein R1* represents hydrogen atom, by treating with appropriate halide such as acetyl chloride like acetyl chloride, propionyl chloride and the hke; alkylchloroformate like methylchloroformate, ethylchloroformate and the like; aralkylchloroformate like benzylchloroformate and the like. The reaction may be carried out in the presence of a solvent such as CH2C12, CHC13, toluene, THF and the like or mixtures thereof The reaction may be carried out in the presence of a base like EtaN, diisopropyl ethylamine, K2CO3, NaH, KOt-Bu and the like. The reaction may be carried 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 R1 represents NHR1* wherein R"* represents acetyl group, may be prepared by reacting compound of formula (I) where R represents azido group, by treating with thioacetic aC1d.


The compound of formula (I) where R1 represents azido group may be converted to a compound of formula (I) where R1 represents NHR"* wherein R1* represents acetyl group by using thioacetic aC1d, with or without using a solvent 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 NHR1*, wherein R^ represents -C(=S)-R^^ wherein R^" represents (C1-C6)alkyl, halo(C1-C6)alkyl, -C(=0)-(C1-C6)alkoxy, -C(=0)-aryloxy, -C(=S)-(C1-C6)alkyl or -C(=S)-aryl; from compound of formula (I), where R1 represents NHR", wherein R1' represents -C(=0)-R1*'', wherein R1*"' represents (C1-C6)alkyl. halo(C1-C6)alkyl, C(=0)-(C1-C6)alkoxy, -C(=0)-aryloxy, -C(=S)-(C1-C6)alkyl or -C(=S)-aryl.

where all symbols are as defined earlier.
Conversion of compound of formula (I), where R1 represents NHR"^, wherein R1* represents -C(=0)-R1'^ wherein R^'' represents (C,-C6)alkyl, halo(C1-C6)alkyl, -C(=0)-(C1-C6)alkoxy, -C(=0)-aryloxy, -C(=S)-(C1-C6)alkyl or -C(=S)-aryl; to a compound of fomula (I), where R1 represents NHR1*, wherein R1* represents -C(=S)-R1"', wherein R1'*' represents (C1-C6)alkyl, halo(C1-C6)alkyl -C(=0)-{C1-C6)alkoxy, -C(=0)-aryloxy, -C(=S)-(C1-C6)alkyl or -C(=S)-aryl; may be carried out by taking a solution of the amide and Lawesson's reagent (2,4-bis(methoxyphenyI)-l,3-dithia-2,4-diphosphetane-2,4-disulfide) 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 NHR"*, wherein R"* represents -

C(=S)-SR1*^ wherein R"*' represents (C1-C6)alkyl group; from compound of formula (I) where R1 represents NHR"* wherein R"* represents hydrogen atom,

where all other symbols are as defined earlier.
The compound of fomula (I), where R1 represents NHR", wherein R1* represents -C(=S)-SR1*^ wherein R^'^ represents (C1-C6)alkyl group, may be prepared from compound of formula (I) where R1 represents NHR"* wherein R1* represents hydrogen atom, by using CS2 in the presence of a base such as EtsN, diisopropyl ethylamine, K2CO3, NaH, KOt-Bu and the like, followed by the appropriate alkylhalide such as methyliodide, ethylbromide, propylbromide and the like. The reaction may be carried out in the presence of a solvent such as water, ethanol, methanol, isopropanol, CH3CN and the like, or mixtures thereof The reaction may be carried at a temperatiire 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 NHR1', wherein R^ represents -C(=S)-OR^'', R^*^ represents (C1-C6)alkyl, cyclo(C3-C6)alkyl, -(C=0)-(C,-C6)alkyl group substituted with fluorine; aryl, halo(C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(Cr C6)alkyl or (C2-C6)alkenyl, which comprises:
(i) converting the compound of formula (I) where R1 represents NHR"* wherein R"* represents hydrogen atom, to a compound of formula (I) where R1 represents isothiocyanate group,
where all other symbols are as defined earlier,
(ii) converting the compoimd of formula (I) where R1 represents isothiocyanate group, to a
compound of formula (I) where R1 represents NHR1*, wherein R"* represents -C(=S)-OR ,

wherein R^'' represents (C1-C6)alkyl, cyC1o(C3-C6)aIkyI, , -(C=0)-(C1-C6)alkyl group substituted with fluorine; aryl, halo(C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)aIkoxy(C1-C6)alkyl or (C2-C6)alkenyl group and all other symbols are as defined earlier.
The compound of fomula (I) where R1 represents isothiocyanate group, may be prepared fi-om compound of formula (I) where R1 represents NHR1* wherein K^ represents hydrogen atom, by using thiophosgene, in the presence of a base such as Et3N, K2CO3, NaOH and the like. The reaction may be carried out in the presence of a solvent such as ethanol, methanol, isopropanol, CH2C12, 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.
The compound of formula (I) where R1 represents NHR1*. wherein R"* represents -C(=S)-OR^'', wherein R"*** represents (C1-C6)alkyl, cyclo(C3-C6)alkyl, -(C=0)-(C1-C6)alkyl group substituted with fluorine; aryl, , halo(C1-C6)alkyl, hydroxy(C1-C6)alkyi, (C1-C6)alkoxy(C1-C6)alkyl or (C2-C6)alkenyi, is prepared from the compound of formula (I) where R1 represents isothiocyanate group, by using respective alcohol such as methanol, ethanol, propanol, cylcohexanol and the like, in the presence of a base such as NaH, LiH, KH and the like The reaction may be carried out in the presence of a solvent 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 NHR"*, wherein R"* represents -C(=S)-N(R1R"), wherein R1 represents hydrogen, (C1-C6)alkyl, (C2-C6)alkenyl, substituted or unsubstituted aralkyl, heteroaralkyl, hydroxy(C1-C6)alkyl, R" represents hydrogen or (C1-C6)alkyl or the two R1 and R" groups together form a 5 or 6 membered cyclic structures containing one or two hetero atoms; from a compound of formula (I) where R1 represents isothiocyanate group,


where all other symbols are as defined earlier.
The compourid. of formula (I), where R1 represents NHR", wherein R* represents -C(=S)-N(R1R"), where in R1 and R" independently represent hydrogen, is prepared by passing ammonia gas into a solution of compound of formula (I) where R1 represents isothiocyanate group, by using a solvent 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 min to 4 h, preferably 30 min.
The compound of formula (I), where R1 represents NHR^, wherein R"* represents -C(=S)-N(R1R"), R1 represents hydrogen, (C1-C6)alkyl, (C2-C6)alkenyl, substituted or unsubstituted aralkyl, heteroaralkyl, hydroxy(C1-C6)alkyl, R" represents hydrogen or (C1-C6)alkyl or R1 and R" groups together form a 5 or 6 membered cyclic structures containing one or two hetero atoms, is prepared by treating compound of formula (I) where R1 represents isothiocyanate group, by using appropriate amine such as methylamine, ethylamine, dimethylamine, diethylamine, benzylamine, aniline, proline, morpholine, thiomorpholine, pyridiylmethylamine and the like, in the presence of a solvent 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 yet another embodiment of the present invention there is provided a process for the preparation of compound of formula (I) where Z represents NR1' wherein R^ represents hydrogen, Y' represents '=0' group, Y2 and Y2 independently represent hydrogen atom, from a compound of formula (I) where Z represents NR"' wherein R*' represents (C1-C6)alkyl group substituted with hydroxy group, Y' represents '=0 group', Y2 and Y2 independently represent hydrogen atom,


where all other symbols are as defined earlier.
The compound of formula (I) where Z represents NR*' wherein R*' represents hydrogen, Y' represents '=0' group, Y2 and Y"' independently represent hydrogen atom, from a compound of formula (I) wherein Z represents NR*' wherein R^ represents (C1-C6)alkyl group substituted with hydroxy group at the a-position, Y' represents '=0 group', Y2 and Y2 independently represent hydrogen atom, may be prepared by treating with a base such as triethylamine, di-isopropylamine, di-isopropylethylamine, pyridine, piperidine, 4-dimethylaminopyridine (DMAP), l,8-diazabicyclo[5.4.0]undec-7-ene (DBU), lithium diisopropylamide (LDA), potassium bis-(trimethyl silyl)amide, BuLi, Na2C03, K2CO3, NaOH, KOH, NaOMe, NaOEt, NaOiPr, t-BuOK, NaH, KH and the like. The solvents used in the reaction may be selected from THF, ether, dioxane, toluene, benzene, DMF, DMSO, acetamide and the like. The temperature of the reaction may be maintained in the range of-20 to 150 °C, preferably in the range of-10 to 100 °C. The duraion of the reaction may be in the range of 0.2 to 64 h, preferably in the range of 1 to 48 h.
In still another embodiment of the present invention there is provided a process for the preparation of compound of formula (I), where Z represents NR1' wherein R^ represents substituted or unsubstituted (C1-C6)alkyl or aralkyl, Y' represents '=0 group', Y2 and Y2 independently represent hydrogen atom; from a compound of formula (I) where Z represents NR1' wherein R1' represents hydrogen, Y' represents '=0' group, Y2 and Y2 independently represent hydrogen atom,

where all other symbols are as defined earlier.
The compound of formula (I), wherein Z represents NR1' wherein R1' represents substituted or unsubstituted (C1-C6)alkyl or aralkyl, Y' represents '=0 group', Y2 and Y2

independently represent hydrogen atom, from a compound of formula (I) wherein Z represents NR" wherein R^ represents hydrogen, Y' represents '=0' group, Y" and Y2 independently represent hydrogen atom, may be carried out in the presence of a base such as triethylamine. di-isopropylamine. di-isopropylethylamine, pyridine, piperidine, DMAP. 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), lithium diisopropylamide (LDA), potassium bis-(trimethyl silyl)amide, BuLi, Na2C03, K2CO3, NaOH, KOH, NaOMe, NaOEt, NaOiPr, t-BuOK, NaH, KH and the like, followed by reacting with alkylhalide such as methyliodide, methoxymethylchloride, allylbromide, benzylbromide and the like. The solvent used in the reaction may be selected from DMF, DMSO, THF, dioxane, benzene, toluene and the like. The temperature of the reaction may be maintained in the range of-5 to 150 °C, preferably in the range of 0 °C to reflux temperature of the solvent. The duraion of the reaction may be in the range of 0.2 to 48 h, preferably in the range of 0.5 to 24 h.
In another embodiment of the present invention there is provided a process for the preparation of a compound of formula (I) where R1 represents halogen, from compound of formula (!) where R1 represents hydroxy group,

where all other symbols are as defined above.
The compound of formula (I) where R1 represents halogen is prepared from compound of formula (I) where R1 represents hydroxy group may be carried out by treating with tetrahalomethane group such as CBr4, CC14 and the like, in the presence of PPha, P(alkyl)3 and the like. The reaction may be carried out in the presence of a solvent such as dry dichloromethane, chloroform, tetrachloromethane, benzene, DMF, DMSO, THF and the like. The temperature of the reaction may be maintained in the range of 0 to 60 °C, preferably at room temperature. The duration of the reaction may be in the range of 2 to 24 h, preferably 8 to 13h.


where all other symbols are as defined earlier, with a base and thioacetic aC1d,
(ii) reacting the compound of formula (XX), to produce a compound of formula (I) where
R1 represents 'SH' group and all other symbols are as defined earlier, with base.
The compound of formula (XX) is prepared from compound of formula (I) where R1 represents hydroxy group is prepared by using thioacetic aC1d in the presence of a base such as triethylamine, di-isopropylamine, di-isopropylethylamine, pyridine, piperidine, DMAP, 1,8-diazabicyC1o[5.4.0]undec-7-ene (DBU), lithium diisopropylamide (LDA), potassium bis-(trimethyl silyl)amide, BuLi, Na2C03, K2CO3, NaOH, KOH, NaOMe, NaOEt, NaOiPr, t-BuOK, NaH, KH and the like. The solvent used in the reaction may be seleceted firom THF, benzene, dioxane and the like. The temperature of the reaction is maintained in the range of room temperature to reflux temperature, preferably at reflux temperature. The duration of the reaction is maintained in the range of 2 to 24 h, preferably 6h.
The compound of formula (I), where R1 represents 'SH' group is prepared from compound of formula (XX) by reacting with a base such as K2CO3, NaOH, KOH, BuLi and the like. The reaction may be carried out at a temperature in the range of room temperature to reflux temprature. The duration of the reaction may be in the range of 1 to 24 h.

It is appreC1ated that in any of the above-mentioned reactions, any reactive group in the substrate molecule may be protected according to conventional chemical practice. Suitable protecting groups in any of the above mentioned reactions are tertiarybutyldimethylsilyl, methoxymethyl, triphenyl methyl, benzyloxycarbonyl, tetrahydropyran(THP) etc, to protect hydroxyl or phenolic hydroxy group; N-lert-butoxycarbonyl (N-Boc), N-benzyloxycarbonyl (N-Cbz), N-9-fluorenyl methoxy carbonyl (-N-FMOC), benzophenoneimine, propargyloxy carbonyl (POC) etc, for protection of amino or anilino group, acetal protection for aldehyde, ketal protection for Jcetone and the like. The methods of formation and removal of such protecting groups are those conventional methods appropriate to the molecule being protected.
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 resolving the racemic mixture by conventional methods. The stereoisomers of the compounds forming part of this invention may be prepared by using reactants in their single enantiomeric form in the process wherever possible or by conducting the reaction in the presence of reagents or catalysts in their single enantiomer form or by resolving the mixture of stereoisomers by conventional methods. Some of the preferred methods include use of microbial resolution, resolving the diastereomeric salts formed with chiral aC1ds such as mandelic aC1d, camphorsulfonic aC1d, tartaric aC1d, lactic aC1d, and the like wherever applicable or chiral bases such as bruC1ne, C1nchona alkaloids and their derivatives and the like. Commonly used methods are compiled by Jaques et al in "Enantiomers, Racemates and Resolution" (Wiley IntersC1ence, 1981). Where appropriate the compounds of formula (I) may be resolved by treating with chiral amines, aminoaC1ds, aminoalcohols derived from aminoaC1ds; conventional reaction conditions may be employed to convert aC1d into an amide; the diastereomers may be separated either by fractional crystallization or chromatography and the stereoisomers of compound of formula (I) may be prepared by hydrolyzing the pure diastereomeric amide.
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, so.dium hydride, potassium t-butoxide, calC1um hydroxide, magnesium hydroxide and the like, in solvent like ether, THF, methanol, t-butanol, dioxane, isopropanol, ethanol and the like. Mixture of solvents may be used. Organic bases like lysine, arginine,.

diethanolamine, choline, tromethamine, guanidine and their derivatives etc. may also be used. Alternatively, aC1d addition salts wherever applicable are prepared by treatment with aC1ds such as hydrochloric aC1d, hydrobromic aC1d, nitric aC1d, sulfuric aC1d, phosphoric aC1d, p-toluenesulphonic aC1d, methanesulfonic aC1d, acetic aC1d, C1tric aC1d, maleic aC1d salicylic aC1d, hydroxynaphthoic aC1d, ascorbic aC1d, palmitic aC1d, sucC1nic aC1d, benzoic aC1d, benzenesulfonic aC1d, tartaric aC1d and the like in solvents like ethyl acetate, ether, alcohols, acetone, THF, dioxane etc. Mixture of solvents may also be used. The salts of amino aC1d groups and other groups may be prepared by reacting the compounds of formula (I) with the respective groups in solvent like alcohols, ketones, ether and the like. Mixture of solvents may be used.
Various polymorphs of a compound of general formula (I) forming 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 pharmaceutically employed carriers, 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 assoC1ated with multidrug resistance.
Pharmaceutically acceptable solvates of compound of formula (I) forming part 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 pharmaceutical compositions may be in the forms normally employed, such as tablets, capsules, powders, syruns. solutions, suspensions and the like, may contain flavorants,

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 I to 10 % by weight of active compound, the remainder of the composition being pharmaceutically acceptable carriers, diluents or solvents.
The invention is explained in detail in the examples given below which are provided by way of illustration only and therefore should not be construed to limit the scope of the invention.
General procedure for preparations 1-9:
A mixture of .appropriate nitro compound such as 4-fluoronitrobenzene and the like, a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group, (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%.

concentrated. The residue obtained was suspended in pet. ether and filtered. The sohds were
collected to afford the nitro compound (4.1 g, 64 %) as yellow crystals.
'H NMR (DMSO+CDC13, 200 MHz): 5 7.97 (d, J=9.3 Hz, 2H), 7.09 (bs, IH), 6.62 (d. J=9.3
Hz, 2H), 2.80-3.40 (m, 6H). Mass(C1 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) (obtained in preparation 10) 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 sihca gel to afford the product (3 g, 66 %) as yellow solid.
'H NMR (CDC13, 200 MHz): 5 8.17 (d, J=9.3 Hz, 2H), 7.75 (d, J=9.2 Hz, 2H), 7.07 (bs, IH), 4.00 (t, J=8.8 Hz, 2H), 3.59 (t, J=8.8 Hz, 2H). Mass(C1 method): 207. 151, 105. Preparation 12: l-Metliyl-3-(4-nitrophenyl)-2-imidazoIidinone

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) (obtained in preparation 11) 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.
'H NMR (CDC13, 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(C1 method): 222. Preparation 13: l-(3-Fluoro-4-nitrophenyl)-4-imidazolidinone


A solution of 4-imiC1azoIidinone (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. 'H NMR (DMSO, 200 MHz): 5 8.81 (bs, IH), 8.07-7.96 (m, 2H), 6.82 (t, J=8.8 Hz, IH), 4.97 (s, 2H), 4.06 (s, 2H). Mass (C1 method): 226, 185, 152. Preparation 14: Nl-phenyl-2-azidoacetamide

Chloroacetyl chloride (5.1 ml, 64.5 mmol) was added drop wise to a solution of aniline (5 g, 53.7 mmol) and EtaN (18.7 ml, 134.3 mmol) in dichloromethane (150 ml) at 0°C 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 NaN3 (6.15 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 %).
'H XMR (DMSO+CDC13. 2CKJ MHz); 5 9.74 (bs, IH), 7.84-8.00 (m, 2H), 7.58 (d, J=8.3 Hz, 2H). ".30 {d, J=8.3 Hz, 2H), '.08 (ra. IH), 6.66 (t, J=8.8 Hz, IH), 6.45 (bs, IH), 4.09 (d, J=5.4 Hz. 2H). Mass (C1 Method): 290.

Preparation 16: Nl-(2-anilinoethyl)-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) (obtained in preparation 15) 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 %). 'H NMR (CDC13, 200 MHz): 5 8.02-7.86 (m, 2H), 7.26-7.18 (m, 2H), 6.82-6.62 (m, 4H), 4.94 (bs, IH), 3.83 (bs, IH), 3.51 (s, 4H). Mass (C1 method): 274. Preparation 17: l-(2-Fluoro-4-nitrophenyi)-3-phenyl-2-imidazoIidinone

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) (obtained in preparation 16) and EtsN (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 %). 'H NMR (CDC13, 200 MHz): 5 8.10-7.11 (m, 8H), 4.22-4.00 (m, 4H). Mass (C1 Method): 302, 106.

Preparation 18: l-(2-Fluoro-4-nitrophenyI)o-nyaroxymemyl-4-imidazolidinone

A mixture of l-(3-fluoro-4-nitrophenyI)-4-imidazoIidinone (9 g, 40 mmol) (obtained in preparation 13) and 40% solution of formaldehyde (100 mL) was heated to reflux for 4 h. The reaction mixture was allowed to cool to room temperature and ice water mixture was added. The preC1pitated solid was filtered and dried to give the product as yellow solid (8.5 g, 83% yield).
'H NMR (DMSO-d', 200MHz): 5 8.10-7.95 (m, 2H), 6.90-6.80 (m, IH), 6.20 (t, J = 6.8 Hz, IH), 5.13 (d, J = 2.9 Hz, 2H), 4.77 (d, J = 7.3 Hz, 2H), 4.19 (s, 2H). Mass (C1 method): 226. Preparation 19: l-(2-Fluoro-4-nitrophenyl)-3-hydroxymethyI-4-imidazoIidinone

A solution of l-(2-fluoro-4-nitrophenyl)-3-hydroxymethyl-4-imidazolidinone (6.7 g, 26.2 mmol) (obtained in preparation 18), pyridinium p-toluenesulphonate (PPTS) (65 mg, 0.39 mmol) and 3,4-dihydro-2//-pyran (3.6 mL, 19.4 mmol) in dichloromethane (100 mL) was stirred at room temperature under argon overnight. The reaction mixture was diluted with dichloromethane (400 mL), washed with half-saturated brine (2^100 mL) and dried. The residue obtained upon evaporation of solvent was passed through a column of silica gel to afford the product as yellow solid (7 g, 79% ).
'H NMR (CDC13, 200MHz): 5 8.05-7.85 (m, 2H), 6.60-6.45 (m, IH), 5.30-4.70 (m, 5H), 4.17 (s, 2H), 4.20-3.30 (m, 4H), 2.00-1.40 (m, 6H). Mass (C1 method): 340, 256, 237.

Preparation 20: General procedure for the conversion of

where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group and 'AR1 represents substituted or unsubstituted 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 NaaCOs (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

where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected fi-om oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group and 'AR1 represents substituted or unsubstituted phenyl ring.
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-glyC1dyl 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 NH4C1 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.

where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group and 'AR1 represents substituted or unsubstituted phenyl ring.
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 NaNa (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.
Examples 20-31 have been prepared according to the general procedure B

where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or imsubstituted phenyl group and 'AR1 represents substituted or unsubstituted 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 filtered 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.



where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group and 'AR1 represents substituted or unsubstituted phenyl ring.
A solution of amine in methyl formate 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 D


where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group; 'AR1 represents substituted or unsubstituted phenyl ring and R1** represents (C1-C6)alkyl, (C1-C6)aikoxy, (C2-C6)alkenyl, halo(C1-C6)alkyI, aryloxy, (C2-C6)alkenyloxy, aryloxycarbonyl or (d-C6)alkoxycarbonyl.
To a solution of the amine (1 eq) in dry dichloromethane at 0 "C under argon was added EtsN (2.5 eq) followed by respective aC1d 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

where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group; 'AR1 represents substituted or unsubstituted phenyl ring and R1"' represents (C1-C6)alkyl, halo(C1-C6)alkyl, -C(=0)-{C,-C6)alkoxy, -C(=0)-aryloxy, -C(=S)-(CrC6)alkyl or -C(=S)-aryl.
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.

where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected fi-om oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group and \\R1 represents substituted or unsubstituted phenyl ring.
To a solution of the amine (1 eq), EtsN (2.2 eq) in dry dichloromethane methyl chloroformate under argon was added at 0 X (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.



where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group; 'AR1 represents substituted or unsubstitiited phenyl ring and R"**^ represents (C1-C6)alkyl group.
To an ice cold mixture of amine (1 eq), Et3N (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 NaHCOj, water, brine and dried. The residue obtained was passed through column to afford the product.



where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group and 'AR1 represents substituted" or unsubstituted phenyl ring.
Thiophosgene (1.2 eq) was added drop wise to a solution of the amine (1 eq), EtaN (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.


where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group; 'AR1 represents substituted or unsubstituted phenyl ring and R^" represents (C1-C6)alkyl, cyclo(C3-C6)alkyl, -(C=0)-(C1-C6)alkyl group substituted with fluorine; aryl, halo(C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C,-C6)alkoxy(C1-C6)alkyI or (C2-C6)alkenyl,.
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.

re 'AR1 represents substituted or unsubstituted phenyl ring
Sodium hydride (360 mg, 7.5 mmol) was added to a solution of starting material (300 mg, 0.75 mmol) in dry THF (30 mL) and the resultant suspension was stirred at room temperature overnight. The reaction mixture was diluted with ethyl acetate (150 mL) and washed with water, brine and dried. The residue obtained upon evaporation of solvent was passed through a column of silica gel to afford the product as a colorless solid (150 mg, 54% yield).


To a solution of starting material (1 eq) in dry DMF was added NaH (1.2 eq) at 0 °C under argon followed by appropriate alkyl halide or aralkyl halide (1.2 eq). The reaction mixture was stirred for 2-6 h while monitoring by TLC. After the consumption of starting material, the reaction mixture was diluted with ethyl acetate and washed with water, brine and dried. The residue obtained upon evaporation of solvent was passed through a column of silica gel to afford the product.



where 'Ox' represents a five membered heterocyclic group, containing two heteroatoms selected from oxygen, nitrogen or sulflur, and is substituted by an =0 or =S group, the heterocycle may also be fused with substituted or unsubstituted phenyl group; 'AR1 represents substituted or unsubstituted phenyl ring; R1 represents hydrogen, (C1-C6)alkyl, (C2-C6)alkenyl, substituted or unsubstituted aralkyl, heteroaralkyl, hydroxy(C1-C6)alkyl and R" represents hydrogen or alkyl or the two R1 and R" groups together form a 5 or 6 membered cyclic structures containing one or two hetero atoms.
Ammonia gas (or appropriate amine) was bubbled to a solution of isoihiocyanate 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 130-143 have been prepared according to the general procedure L

Nl-((5S)-3-{3-fluoro-4-[3-benzyl-4-oxo-l-imidazolidinyl]phenyl}-2-oxo-l,3-oxazolan-5-ylmethyl)ethylthiocarbamate (obtained in example 121), was taken in methanol (100 mg) and was bubbled with HCl gas for 30 min. Then methanol was evaporated from the resultant mixture and washed with ether twice to obtain the title compound (Yield: 100%). Mp: 100 °C (hygroscopic).
'H NMR (DMSO-d^200 MHz): 8 10.60 (bs, IH), 9.85-9.65 (m, IH), 7.58 (s, 4H), 5.00-4.65 (m, 3H), 4.44 (t, J= 7.6 Hz, 2H), 4.25-3.40 (m, 8H), 2.81 (s, 3H), 2.79 (s, 3H).

Claims
1. A process for the preparation of the compound of formula (I)

where R1 represents ■NHR1*, wherein R1* represents hydrogen atom; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SRa, Na OR1' where R^ 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, (d-C6)alkoxy, aryi, 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, 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, (d-C6)alkoxycarbonyl, (C1-C6)alkanoic aC1d, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)aIkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, mono(C1-C6)alkylamino, di(C1-C6)alkylamino, arylamino, (C1-C6)aIkoxy, aryl, aryloxy, aralkyl. heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y^ and Y' when present on adjacent carbon atoms together 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 (III)

where Y', Y^ Y^ and Z are as defined above, with a compound of formula (IV), in the presence of a base, a solvent, by using inert atmosphere at a temperature in the range of 20 to 180 °C and duration in the range of 1 to 15 h,

where R1 represents NHR"* wherein R1* represnts hydrogen atom; Y1, Y2, Y3 R2, R3 and Z are as defined above, in the presence of a catalyst, a solvent, at a pressure in the range of atmospheric pressure to 60 psi, temperature in the range of 25 to 60 °C and duration in the range of 2 to 48 h.
2. The process as claimed in claim 1, wherein the base used in step (i) of the reaction is
selected from KOH, NaOH, K2CO3, Na2C03, NaH, KH, triethylamine or diisopropylethyl
amine.
3. The process as claimed in claims 1-2, wherein the solvent used in step (i) of the reaction
is selected from DMSO, DMF, THF, l-methyl-2-pyrroHdinone, acetamide, toluene, xylene,
acetonitrile, chloroform or mixtures thereof

4. The process as claimed in claims 1-3, wherein the inert atmosphere is maintained in step (i) of the reaction by using N2, He or Ar.
5. The process as claimed in claims 1-4, wherein the temperature and pressure in step (i) are maintained in the range of ambient to 80 "C and 6 to 12 h respectively.
6. The process as claimed in claims 1-5, wherein the catalyst used in the step (ii) of the reaction is selected from Ru, Pd, Rh, Pt, Ni on solid beads charcoal, alumina or asbestos.
7. The process as claimed in claims 1-6, wherein the solvent used in the step (ii) of the reaction is selected from dioxane, acetic aC1d, ethyl acetate, THF, methanol, ethanol or mixtures thereof
8. The process as claimed in claims 1-7, wherein the metal/mineral aC1d used in step (ii) of the reaction is selected from Sn/HCl, Fe/HCl, Zn/HCl or Zn/CH3C02H.
9. The process as claimed in claims 1-8, wherein the room temperature is maintained in step (ii) of the reaction.
10. The process as claimed in claims 1-9, wherein the alkylchloroformate used in the step (iii) of the reaction is selected from methychloroformate, ethylchloroformate, propylchloroformate or benzylchloroformate.
11. The process as claimed in claims 1-10, wherein the solvent used in the step (iii) of the reaction is selected from water, acetone, tetrahydroftiran, acetonitrile, dichloromethane or mixtures thereof
12. The process as claimed in claims 1-11, wherein the base used in step (iii) of the reaction is selected from K2CO3, Na2C03, NaH, KOH or triethylamine.
13. The process as claimed in claims 1-12, wherein the temperature and duration of the reaction in step (iii) are maintained in the range of 0 °C to room temperature and 1 to 4 h respectively.
14. The process as claimed in claims 1-13, wherein the alkalimetalhydride used in step (iv) of the reaction is selected from NaH or KH
15. The process as claimed in claims 1-14, wherein the organolithium used in step (iv) of the reaction is selected from CHsLi, BuLi or LDA.
16. The process as claimed in claims 1-15, wherein the alkoxide used in step (iv) of the reaction is selected from NaOMe, NaOEt or t-BuOK.

17. The process as claimed in claims 1-16, wherein the solvent used in step (iv) of the reaction is selected from THF, dioxane, DMF, DMSO, DME or mixtures thereof.
18. The process as claimed in claims 1-17, wherein the co-solvent used in step (iv) of the reaction is selected from hexamethylphosphamide.
19. The process as claimed in claims 1-18, wherein the temperature of the reaction m step (iv) of the reaction is maintained in the range of-78 to 30 °C.
20. The process as claimed in claims 1-19, wherein the alkylsulfonyl chloride or aryl sulfonyl chloride used in step (v) of the reaction is seleceted from methanesulfonyl chloride or p-toluenesulfonyl chloride
21. The process as claimed in claims 1-20, wherein the solvent used in the step (v) of the reaction is selected from dimethylformamide, dimethyl sulfoxide, acetamide, chloroform, dichioromethane, THF, dioxane or mixtures thereof.
22. The process as claimed in claims 1-21, wherein the base used in step (v) of the reaction is selected from EtsN, diisopropyl ethylamine, Na2C03 or K2CO3,
23. The process as claimed in claims 1-22, wherein the temperature and duration of the reaction in step (v) of the reaction are maintained in the range of room temperature to 80 °C and 1 to 4 h respectively.
24. The process as claimed in claims 1-23, wherein the catalyst used in the step (vi) of the reaction is selected from Ru, Pd, Rh, Pt, Ni on solid beads charcoal, alumina or asbestos; or PPh3 in water.
25. The process as claimed in claims 1-24, wherein the solvent used in the step (vi) of the reaction is selected from dioxane, acetic aC1d, ethyl acetate, THF, methanol, ethanol or mixtures
thereof.
26. The process as claimed in claims 1-25, wherein the temperature in step (vi) of the reaction is maintained at room temperature.
27. A process for the preparation of compound of formula (I)

where R1 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, SR1, NR1, OR1

where R1 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)aIkoxy, aryi, aralkyl, aryloxy, (C,-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y' represents =0 or =S group and Y^ and Y^ independently represent hydrogen, halogen, cyano, nitro, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-C6)alkyK hydroxy(CrC6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, (C1-C6)alkanoic aC1d, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyIoxy(C1-C6)alkyl, amino(C1-C6)alkyL mono(C1-C6)alkylamino, di(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; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates; which comprises:



where R^ Y', Y^ Y^, R^, R^ and Z are as defined above, by using an aC1d, a solvent, at a temperature in the range of 30 to 100 °C and duration in the range of 10 min to 5 h and (iii) cyclising the compound of formula (XVI) with or without a base to a compound of formula (I), where R1 represents hydroxy group; Y', Y^ Y\ R^ R^ and Z are as defined above,

in the presence of a base, a solvent at a temperature in the range of room temperature to 150 °C and duration in the range of 2 to 4 h..
28. The process as claimed in claim 27, wherein the base used in step (a)(i) of the reaction is selected from K2CO3, NaH or t-BuOK.
29. The process as claimed claims 27 and 28, wherein the solvent used in step (a)(i) of the reaction is selected from DMF, toluene, THF, CH3CN or mixtures thereof
30. The process as claimed claims 27-29, wherein the Lewis aC1d used in the step (a)(i) of the reaction is selected from BF3.0Et2, ZnCh, Ti(0iPr)4 or lanthanide metal complexes along with the solvent DCE, DMF, THF or mixtures thereof
31. The process as claimed in claims 27-30, wherein the temperature and duration of the reaction in step (a)(i)' of the reaction are maintained in the range of 0 to 100 "C and 4 to 12 h respectively.
32. The process as claimed in claims 27-31, wherein the carbonylating agent used in step (a)(ii) of the reaction is selected from dialkyl carbonate, dihalo carbonyl or 1,1'-carbonyldiimidazole.
33. The process as claimed in claims 27-32, wherein the base used in step (a)(ii) of the reaction is selected from triethylamine, tributylamine, diisopropylethylamine, 1,4-diazabicyclo[2.2.2]octane (DABCO), l,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,1.5-diazabicyclo[4.3.0]non-5-ene (DBN), NaOMe, NaOEt, NaOH or KOH.
34. The process as claimed in claims 27-33, wherein the solvent used in step (a)(ii) of the reaction is selected from dichloromethane, tetrahydrofuran, dimethylformamide or ethylacetate.
35. The process as claimed in claims 27-34, wherein the temperature and duration of the reaction in step (a)(ii) of the reaction is maintained in the range of 15 to 80 "C and 2 to 50 h respectively.
36. The process as claimed in claim 27, wherein the base used in step (b)(i) of the reaction is selected from K2CO3, NaH, t-BuOK or LDA.
37. The process as claimed in claims 27 and 36, wherein the solvent used in the step (b)(i) of the reaction is seleceted from DMF, THF, DMSO or EtOH.
38. The process as claimed in claims 27, 36 and 37, wherein the temperature and duration in step (i) of the reaction are in the range of-78 to 100 °C and 2 to 20 h respectively.

39. The process as claimed in claims 27 and 36-38, wherein the aC1d used in step (b)(ii) of the reaction is selected from HCl, H2SO4, aqueous acetic aC1d, p-toluene sulfonic aC1d, camphorsulfonic aC1d or trifluoro acetic aC1d.
40. The process as claimed in claims 27 and 36-39, wherein the solvent used in step (b)(ii) of the reaction is selected from water, methanol, THF, dioxane or mixtures thereof
41. The process as claimed in claims 27 and 36-40, wherein the temperature and duration of the reaction in step (b)(ii) of the reaction is in the range of 30 to 60 "C and 30 min to 2.5 h respectively.
42. The process as claimed in claims 27 and 36-41, wherein the base used in step (b)(iii) of the reaction is selected from aOMe, K2CO3 or NaH.
43. The process as claimed in claims 27 and 36-42, wherein the solvent used in step (b)(iii) of the reaction is selected from MeOH, DMF or THF.
44. A process for the preparation of compound of the formula (I)

where R1 represents azido; R^ and R^ are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SR^ NR\ OR^ where R* represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C)-C6)alkyl; Z represents S, 0, =CH or NR"' where R1' represents hydrogen, or substituted or unsubstituted (C\-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl. aralkyl, aryloxy, (d-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y' represents =0 or =S group and Y^ and Y^ independently represent hydrogen, halogen, cyano, nitro, 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, (C,-C6)alkoxycarbonyl, (C1-C6)alkanoic aC1d, (C1 -C6)alkyIsulfonyl, (C1 -C6)alkylcarbonylamino(C 1 -C6)alkyl, arylcarbonylamino(C 1 -Cajalkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, mono(C1-C6)alkylamino, di(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 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

where R1 represents azido group; Y', Y^, Y\ R^, R^ and Z are as defined above by reacting with an organic or an inorganic azide, in the presence of a solvent, inert atmosphere, at a temperature in the range of ambient temperature to reflux temperature of the solvent and duration in the range of 0.5 to 18 h.
45. The process as claimed in claim 44, wherein the base used in step (a)(i) of the reaction
is selected from NaH, KH, K2CO3, t-BuOK, LDA or NaOMe.
46. The process as claimed in claims 44 and 45, wherein the phase transfer catalyst used in
step (a)(i) of the reaction is selected from tetrabutylammonium halide.

47. The process as claimed in claims 44-46, wherein the solvent used in step (a)(i) of the reaction is selected from THF, DMF, DMSO, benzene or mixtures thereof.
48. The process as claimed in claims 44-47, wherein the temperature and duration in step (a)(i) of the reaction are maintained in the range of-78 to 60 °C and 4 to 10 h respectively.
49. The process as claimed in claims 44-48, wherein the solvent used in step (a)(ii) of the reaction is selected from CHC13, CH2C12, THF, DMF, DMSO, acetonitrile or mixtures thereof
50. The process as claimed in claims 44-49, wherein the temperature and duration in step (a)(ii) of the reaction are maintained at ambient temperature and 2 to 12 h respectively.
51. The process as claimed in claims 44-50, whrein the organic or an inorganic azide used in step (a)(iii) of the reaction is selected from LiNs, NaN3 or trialkyl silylazide.
52.- The process as claimed in claims 44-51, wherein the solvent used in step (a)(iii) of the reaction is selected from THF, acetone, DMF, DMSO or mixtures thereof
53. The process as claimed in claim 44-52, wherein the inert atmosphere used in step (a)(iii) of the reaction is maintained by using N2, He or Ar.
54. The process as claimed in claims 44-53, wherein the temperature and duration in step (a)(iii) of the reaction are maintained in the range of 50 to 80 °C and 1 to 4 h respectively.
55. The process as claimed in claims 44-54, wherein the base used in step (b)(i) of the reaction is selected from NaH, NaOMe, K2CO3, n-BuLi or LDA.
56. The process as claimed in claims 44-55, wherein the solvent used in step (b)(i) of the reaction is selected froni DMF, THF, DMSO, benzene or mixtures thereof
57. The process as claimed in claims 44-56, wherein the temperature and duration m step (b)(i) of the reaction are maintained in the range of-78 to 50 °C and 1 to 10 h respectively.
58. The process as claimed in claims 44-57, wherein the organic or an inorganic azide used in step (b)(ii) of the reaction is selected from LiNs, NaNs or trialkyl silylazide.
59. The process as claimed in claims 44-58, wherein the solvent used in step(b)(ii) of the reaction is selected from THF, acetone, DMF, DMSO or mixtures thereof
60. The process as claimed in claims 44-59, wherein the inert atmosphere in step (b)(ii) of the reaction is maintained by using He, N2 or Ar.
61. The process as claimed in claims 44-60, wherein the temperature and duration in step (b)(ii) of the reaction are maintained in the range of 50 to 80 °C and 1 to 4 h respectively.
62. A process for the preparation of compound of the formula (I)


where R1 represents NHR"*, wherein R1* represents acetyl group; R^ and R^ are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SR\ NR*, OR^ where R* 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, aralkyi, 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, 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, (C1-C6)alkanoic aC1d, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C|-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C|-C6)alkyl, mono(C1-C6)alkylamino, di(C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl. aryloxy, aralkyi, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y^ and Y^ when present on adjacent carbon atoms together 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:



where R1 represents NHR1*, wherein R"* represents formyl group; R^ and R^ are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SR*, NR^ OR* where R^ 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, (C|-C6)alkoxycarbonyl or aryloxycarbonyl; Y' represents =0 or =S group and Y^ and Y" independently represent hydrogen, halogen, cyano, nitre, 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 (C,-C6)alkoxycarbonyl, (C|-C6)alkanoic aC1d, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(CrC6)alkyl, amino(C1-C6)alkyl, mono(C1-C6)alkylamino, di(C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryi, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y^ and Y^ when present on adjacent carbon atoms together 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: formylating the compound of formula (I) where R1 represents NHR"* wherein K* represents hydrogen and Y', Y^, Y^, R^, R^ and Z are as defined above, by using alkylformate, at a temperature in the range of 60 to 120 °C and duration in the range of 4 to 48 h.
68. The process as claimed in claim 67, wherein the alkylformate used is selected from methyl formate, ethyl formate or propyl formate.
69. The process as claimed in claims 67 and 68, wherein the temperature and duration of the reaction are maintained at reflux temperature and 12 to 24 h respectively.
70. A process for the preparation of compound of formula (I)

where R1 represents NHR1', wherein R"* represents -C(=0)-R1*^ wherein R"** represents (Cr C6)alkyl, (C,-C6)alkoxy, (C2-C6)alkenyl, halo(C1-C6)alkyl, aryloxy, (C2-C6)alkenyloxy, aryloxycarbonyl or (C1-C6)alkoxycarbonyl; R^ and R^ are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SR", NR\ OR^ where R* represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NR1' where R1' represents hydrogen, or substituted or unsubstituted (C!-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-Cejalkoxy, 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, hydroxy, amino, =0, =S group, or substituted or unsubstituted groups selected from (C1-
C6)alkyl, hydroxy(C1-C6)alkyl, (C,-C6)alkoxy(C,-C6)alkyl, (C1-C6)alkoxycarbonyl, (C,-
C6)alkanoic aC1d, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyi,
arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyI, mono(C1-C6)alkylamino, di(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 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: acetylating the compound of formula (I) where R1 represents NHR"* wherein R1* represents hydrogen; Y', Y^, Y\ R^ R^ and Z are as defined above, by using a halide or alkyIchloroformate or benzylchloroformate, a solvent, a base, at a temperature in the range of-20 to 60 "C and at a duration in the range of 1 to 12 h.
71. The process as claimed in claim 70, wherein the halide used in the reaction is selected from acetyl chloride or propionyl chloride.
72. The process as claimed in claims 70 and 71, wherein the alkylchloroformate used in the reaction is selected from methylchloroformate or ethy Ichloro formate.
73. The process as claimed in claims 70-72, wherein the solvent used in the reaction is selected from CH2C12, CHC13, toluene, THF or mixtures thereof.
74. The process as claimed in claims 70-73, wherein the base used in the reaction is selected from EtsN, diisopropyl ethylamine, K2CO3, NaH or t-BuOK.
75. The process as claimed in claims 70-74, wherein the temperature and duration of the reaction are maintained in the range of 0 to room temperature and 1 to 4 h respectively.
76. A process for the praparation of compound of formula (I)

where R1 represents NHR1*, wherein R"* represents -C(=S)-R1"', wherein R1*'' represents (C1-C6)alkyl, halo(C1-C6)alkyl, -C(=0)-(C1-C6)alkoxy, -C(=0)-aryloxy, -C(=S)-(C,-C6)aIkyl or -C(=S)-aryl; R^ and R^ are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, haIo(CrC6)alkyl, cyano, nitro, SR^ NR\ OR1 where R1 represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyI; Z represents S, 0, =CH or

NR1' 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; Y' represents =0 or =S group and Y"
and Y^ independently represent hydrogen, halogen, cyano, nitro, hydroxy, amino, =0, =S
group, or substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)alkyi.
(C1-C6)aIkoxy(C1-C6)alkyl, (C1-C6)alkoxycarbonyl, (C1-C6)alkanoic aC1d, (C1-C6)alkylsulfonyi,
(C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (d-
C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, mono(C1-C6)alkylamino, di(C1-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyi, heterocyclyl or heterocycloalkyl; Y^ and Y'' when present on adjacent carbon atoms together 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: reacting the compound of formula (I) where R1 represents NHR", wherein R1* represents -C(=0)-R1''', wherein R1"' represents (C1-C6)alkyl,halo(C1-C6)alkyl, -C(=0)-(C1-C6)alkoxy, -C(=0)-aryloxy, -C(=S)-(C|-C6)alkyl or -C(=S)-aryl; Y', Y^ Y\ R^ R^ and Z are as defined above, with 2,4-bis(methoxyphenyl)-l,3-dithia-2,4-diphosphetane-2,4-disuIfide (Lawesson's reagent) in the presence of a solvent at a temperature in the range of room temperature to 130 °C for 3 to 24 h.
77. The process as claimed in claim 76, wherein the solvent used is selected from dioxane, toluene, THF or DMF.
78. The process as claimed in claims 76 and 77, wherein the temperature and duration of the reaction are in the range of 55 to 90 °C and 3 to 10 h.
79. A process for the preparation of compound of formula (I)

where R1 represents NHR"*, wherein R"* represents -C(=S)-SR1''' wherein R1^' represents (C1-C6)alkyl group; R^ and R^ are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C,-C6)alkyl, cyano, nitro, SR\ NR1, OR1 where R1 represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, 0, =CH or

NR1' where R1' 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, 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, (C1-C6)alkanGic aC1d, (C1-C6)aIkylsulfonyl,
(C1-C6)alkylcarbonylimino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-
C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, mono(C1-C6)alkylamino, di(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 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: reacting the compound of formula (I) where R1 represents NHR"*, wherein K^ represents hydrogen; Y', Y\ Y\ R^, R^ and Z are as defined above, by reacting with carbondisulfide, with an alkylhalide in the presence of a base and a solvent at a temperature in the range of room temperature to 60 "C for 6 to 24 h.
80. The process as claimed in claim 79, wherein the alkylhalide used is the reaction is selected from methyliodide, ethylbromide or propylbromide.
81. The process as claimed in claims 79 and 80, wherein the solvent used in the reaction is selected firom water, ethanol, methanol, isopropanol, CH3CN or mixtures thereof.
82. The process as claimed in claims 79-81, wherein the temperature of the reaction is maintained at room temperature.
83. A process for the preparation of compound of formula (I)

where R1 represents NHR"*, wherein R1* represents -C(=S)-OR1^'^, wherein R"*^ represents (C1-C6)alkyl, cyclo(C3-C6)alkyl, -(C=0)-(C1-C6)alkyl group substituted with fluorine, aryl, , halo(C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C,-C6)aIkyl or (C2-C6)alkenyl; R^ and R^ are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl

group, halo(C1-C6)aIkyl, cyano, nitro, SR*, NR1, OR1 where R1 represents substituted or
unsubstituted (C1-C6)alkyl group, or halo(CrC6)alkyl; Z represents S. O, =CH or NR1' where R^
represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl (d-
C6)cycloalkyl, (C1-C6)aIkoxy, aryl, aralkyl, aryloxy, (C1-C6)alkylcarbonyl, arylcarbonyl, (Cp
C6)alkoxycarbonyl or aryloxycarbonyl; Y' represents =0 or =S group and Y" and Y"'
independently represent hydrogen, halogen, cyano, nitro, hydroxy, amino, =0, =S group, or
substituted or unsubstituted groups selected from (C1-C6)alkyl, hydroxy(C1-C6)aIkyl, (d-
C6)alkoxy(C1-C6)alkyl,' (C1-C6)alkoxycarbonyl, (C1-C6)alkanoic aC1d, (C1-C6)alkylsulfonyl.
(C1-C6)aIkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-
C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, mono(CrC6)aIkylamino, di(C|-C6)alkylamino arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyl, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y^ and Y^ when present on adjacent carbon atoms together 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 phamiaceutically acceptable solvates; which comprises:
(i) converting compound of formula (I) where R1 represents NHR1', wherein R^ represents hydrogen atom; Y', Y^, Y\ R^, R^ and Z are as defined above, to a compound of formula (I) where R1 represents isothiocyanate group and all other symbols are as defined above, by reacting with thiophosgene in the presence of a base, a solvent, at a temperature in the range of 0 to 60 °C for 3 to 24 h by using inert atmosphere,
(ii) converting compound of formula (I) where R1 represents isothiocyanate group, to a compound of formula (I) where R1 represents NHR1', wherein R" represents -C(=S)-OR1''^, wherin R1"' represents (C1-C6)alkyl, cyclo(C3-C6)alkyl, -(C=0)-(C1-C6)alkyl group substituted with fluorine, aryl,, halo(C1-C6)alkyl, hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl or (C2-C6)alkenyl and all symbols are as defined above by reacting with alcohol in the presence of a base, a solvent at a temperature in the range of room temperature to 130 °C for 6 to 24 h.
84. The process as claimed in claim 83, wherein the base used in step (i) of the reaction is selected from EtsN, K2CO3 or NaOH.
85. The process as claimed in claims 83 and 84, wherein the solvent used in step (i) of the reaction is selected from ethanol, methanol, isopropanol, CH2C12 or CH3CN.

86. The process as claimed in claims 83-85, wherein the inert atmosphere used in step (i) of the reaction is maintained by using He, Ne or Ar.
87. The process as claimed in claims 83-86, wherein the temperature used in step (i) of the reaction is at 0 "C.
88. The process as claimed in claim 83-87, wherein the base used in step (ii) of the reaction is selected from NaH, LiH or KH.
89. The process as claimed in claims 83-88, wherein the solvent used in step (ii) of the reaction is selected from THF, toluene or DMF.
90. The process as claimed in claims 83-89, wherein the temperature used in step (ii) of the reaction is at reflux temperature of the solvent used.
91. A process for the preparation of compound of formula (I)

where R1 represents NHR1*, wherein K* represents -C(=S)-N(R1R"), R1 represents hydrogen, (C1-C6)alkyl, (C2-C6)alkenyl, substituted or unsubstituted aralkyi, heteroaralkyl, hydroxy(C1-C6)alkyl, R" represents hydrogen or (C1-C6)alkyl or R1 and R" together fomi a 5 or 6 membered cyclic structures containing one or two hetero atoms; R^ and R^ are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, haIo(C1-C6)alkyl, cyano, nitro, SR^, NR*, OR* where R^ represents substituted or unsubstituted (C1-C6)alkyl group, or halo(C1-C6)alkyl; Z represents S, O, =CH or NR1' where R^ represents hydrogen, or substituted or unsubstituted (C1-C6)alkyl, (C2-C6)alkenyl, (C1-C6)cycloalkyl, (C1-C6)alkoxy, aryl, aralkyi, 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, 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, (C,-C6)alkoxycarbonyl, (C1-C6)alkanoic aC1d, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C|-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, mono(C1-C6)alkylamino, di(C|-C6)alkylamino, arylamino, (C1-C6)alkoxy, aryl, aryloxy, aralkyi, heteroaryl, heteroaralkyl, heterocyclyl or heterocycloalkyl; Y^ and Y^ when present on adjacent carbon atoms together 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: converting compound of formula (I) where R1 represents isothiocyante group and all other symbols are as defined above by passing ammonia gas or by reacting with amine, in the presence of a solvent at a temperature in the range of-10 to 140 °C for 1 to 24 h.
92. The process as claimed in claim 91, wherein the solvent used in the reaction is selected from THF, toluene or DMF.
93. The process as claimed in claim 91 and 92, wherein the amine used in the reaction is selected fi-om methylamine, ethylamine, dimethylamine, diethylamme, benzylamine, aniline, proline, morpholine, thiomorpholine or pyridiylmethylamine.
94. The process as claimed in claim 91-93, wherein the temperature and duration maintained in the reaction are in the range of-10 to 100 "C and 30 min to 12 h respectively.
95. A process for the preparation of compound of formula (I)

where Z represents NR1' wherein R"' represents hydrogen, Y' represents '=0' group, Y^ and Y^
independently represent hydrogen atom, R1 represents halo, azido, isothiocyanate, thioalcohol,
OR1*, NHR1* or N(R1*)2 where R1* 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, -(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, -CeS)-C(=S)-aryl, thiomorpholinylthiocarbonyl or pyrrolidinylthiocarbonyl; R^ and R^ may be same or different and independently represent hydrogen, halogen atom, (C1-C6)alky! group, halo(C1-C6)alkyl, cyano, nitro, SR1, NR1, OR1 where R" 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, (Ca-Cejalkenyl, (C1-C6)cycloalkyl, (C,-C6)alkoxy,

aryl, aralkyl, aryloxy, (C1-C6)aIkylcarbonyl, arylcarbonyl, (C1-C6)aIkoxycarbonyl or aryloxycarbonyl its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates; which comprises: reacting the compound of formula (I) where Z represents NR1' wherein R*' represents (C1-C6)alkyl group substituted with hydroxy group at a-position, Y' represents '=0 group', Y and Y^ independently represent hydrogen atom and all other symbols are as defined above, in the presence of a base, a solvent at a temperature in the range of-20 to 150 "C for 0.2 to 64 h.
96. The process as claimed in claim 95, wherein the base used in the reaction is selected from triethylamine,' di-isopropylamine, di-isopropylethylamine, pyridine, piperidine, 4-dimethylaminopyridine (DMAP), l,8-diazabicyclo[5.4.0]undec-7-ene (DBU), lithium diisopropylamide (LDA), potassium bis-(trimethyl silyl)amide, BuLi, Na2C03, K2CO3, NaOH, KOH, NaOMe, NaOEt, NaOiPr, t-BuOK, NaH or KH.
97. The process as claimed in claims 95 and 96, wherein the solvent used in the reaction is selected from THF, ether, dioxane, toluene, benzene, DMF, DMSO or acetonitrile.
98. The process as claimed in claims 95-97, wherein the temperature and duration are maintained in the range of-10 to 100 "C and 1 to 48 h respectively.
99. A process for the preparation of compound of formula (I)

where Z represents NR1' wherein R^ represents substituted or unsubstituted (C1-C6)alkyl or
aralkyl, Y' represents '=0 group', Y^ and Y^ independently represent hydrogen atom; R1
represents halo, azido, isothiocyanate, thioalcohol, OR1', NHR1* or N(R1')2 where R1^ 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, -(C=S)-S-alkyl, -(C=S)-NH2, -(C=S)-NH-alkyl, -C(=S)-N-(aIkyl)2, -C(=S)-NH-alkenyI, (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, 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, SR1, NR". OR1 where R* represents substituted or unsubstituted (C1-Cejalkyi 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-C6)alkyIcarbonyl, arylcarbonyl, (C]-C6)alkoxycarbonyl or aryloxycarbonyl its derivatives, its analogs, its tautomeric forms, its stereoisomers, its polymorphs, its pharmaceutically acceptable salts or its pharmaceutically acceptable solvates; which comprises: reacting the compound of formula (I) where Z represents NR1' wherein R1' represents hydrogen, Y' represents '=0' group, Y^ and Y^ independently represent hydrogen atom and all other symbols are as defined above, in the presence of a base, an alkyl halide and a solvent at a temperature in the range of-5 to 150 "C for 0.2 to 48 h.
100. The process as claimed in claim 99, wherein the base used in the reaction is selected fi-om triethylamine, di-isopropylamine, di-isopropylethylamine, pyridine, piperidine, DMAP, l,8-diazabicyclo[5.4.0]undec-7-ene (DBU), lithium diisopropylamide (LDA), potassium bis-(trimethyl silyl)amide, BuLi, Na2C03, K2CO3, NaOH, KOH, NaOMe, NaOEt, NaOiPr, t-BuOK, NaH or KH.
101. The process as claimed in claims 99 and 100, wherein the alkylhalide used in the reaction is selected from methyliodide, methoxymethylchloride. allylbromide or benzylbromide.
102. The process as claimed in claims 99-101, wherein the solvent used in the reaction is selected from DMF, DMSO, THF, dioxane, benzene or toluene.
103. The process as claimed in claims 99-102, wherein the temperature and duration of the reaction are maintained in the range of 0 °C to reflux temperature of the solvent and 0.5 to 24 h respectively.
104. A process for the preparation of compound of formula (I)

where R1 represents halogen atom; R^ and R"' are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SR1, NR1, OR1

where R* 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)aikyl, (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, 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, (C1-C6)alkanoic aC1d, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)aIkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)alkyl, mono(C1-C6)alkylamino, di(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 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: reacting a compound of formula (I) where R1 represents hydroxy group and all other symbols are as defined above, with tetrahalomethane group in the presence of PPh3 or P(alkyl)3 in the presence of a solvent at a temperature in the range of 0 to 60 "C and duration in the range of 2 to 24 h.
105. The process as claimed in claim 104, wherein the tetrahalomethane group used in the reaction is selected from CBr4 or CC14.
106. The process as claimed in claims 104 and 105, wherein the solvent used in the reaction is selected from dichloromethane, chloroform, tetrachloromethane, benzene, DMF, DMSO or THF.
107. The process as claimed in claims 104-106, wherein the temperature and duration of the reaction are maintained at room temperature and 8 to 13 h respectively.
108. A process for the preparation of compound of formula (I)

where R1 represents 'SH' group; R2 and R3 are same or different and independently represent hydrogen, halogen atom, (C1-C6)alkyl group, halo(C1-C6)alkyl, cyano, nitro, SR^ NR*. OR1

where R^ 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, (C|-C6)alkylcarbonyl, arylcarbonyl, (C1-C6)alkoxycarbonyl or aryloxycarbonyl; Y' represents =0 or =S group and Y^ and Y^ independently represent hydrogen, halogen, cyano, nitro, 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, (C1-C6)alkanoic aC1d, (C1-C6)alkylsulfonyl, (C1-C6)alkylcarbonylamino(C1-C6)alkyl, arylcarbonylamino(C1-C6)alkyl, (C1-C6)alkylcarbonyloxy(C1-C6)alkyl, amino(C1-C6)aikyl, mono(C1-C6)alkylamino. di(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 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 (I) where R1 represents halogen atom, to produce a compound of formula (XX),

where all symbols are as defined above, by using thioacetic aC1d in the presence of a base, a solvent at a temperature in the range of room temperature to reflux temperature for 2 to 24 h, (ii) reacting the compound of formula (XX), to produce a compound of formula (I) where R1 represents 'SH' group and all other symbols are as defined above, in the presence of a base at a temperature in the range of room temperature to reflux temprature for 1 to 24 h. 109. The process as claimed in claim 108, wherein the base used in step (i) of the reaction is selected from triethylamine, di-isopropylamine, di-isopropylethylamine, pyridine, piperidine, DMAP, l,8-diazabicyclo[5.4.0]undec-7-ene (DBU), lithium diisopropylamide (LDA), potassium bis-(trimethyl silyl)amide, BuLi, NajCOa, K2CO3, NaOH, KOH, NaOMe, NaOEt, NaOiPr, t-BuOK, NaH or KH.

110. The process as claimed in claims 108 and 109, wherein the solvent used in step (i) of the reaction is selected from THF, benzene or dioxane.
111. The process as claimed in claims 108-110, wherein the temperature and duration in step (i) of the reaction are maintained at reflux temperature and 6 h respectively.
112. The process as claimed in claims 108-111, wherein the base used in step (ii) of the reaction is selected from K2CO3, NaOH, KOH or BuLi.