Field of Invention
The present invention relates to a process for the preparation of novel anti-inflammatory compounds, their derivatives, their analogs, their tautomeric forms, their stereoisomers, their regioisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutically acceptable compositions containing them. More particularly, the present invention relates to a process for the preparation of novel heterocyclic compounds of the general formula (I), their derivatives, their analogs, their tautomeric forms, their stereoisomers, their regioisomers, their polymorphs, their pharmaceutically acceptable salts, their pharmaceutically acceptable solvates and pharmaceutically acceptable compositions containing them.

wherein R1 represents amino or substituted or unsubstituted groups selected from alkyl, alkylamino, acylamino, cycloalkyl, cyclicamino, carboethoxycarbonylalkyl, hydrazine, hydrazido, aminoacid residue, aryl, heteroaryl or ~N-CR(NR)2 where R represents hydrogen or lower alkyl group; R2 represents halogen, hydroxy, cyano, nitro, azido, formyl, oximealkyl, thio or substituted or unsubstituted groups selected from amino, alkyl, alkoxy, hydrazine, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residue, aminoacid residuealkyl, acyl, carbonyloxyalkyl, haloalkyl, aminoalkyl, haloalkoxy, hydroxyalkyl, alkoxyalkyl, thioalkyl, alkylthio, alkylsulfmyl, alkylsulfonyl, aryl, aralkyl, aryloxy, aralkoxy, aryloxyalkyl, aralkoxyalkyl, carboxamidoalkyl, carbonylaminoalkyl groups or when the groups -S(=0)m-R' and R2 are present on adjacent carbon atoms, R1 and R2 together with atoms to which they are attached may also form a substituted or unsubstituted 5-7 membered cyclic structure containing carbon atoms, a sulfur atom and may optionally contain one or two heteroatoms selected from 0, S or N; R3 represents hydrogen, halogen atom, hydroxy, nitro, cyano, azido or substituted or unsubstituted groups selected from hydrazine, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residues, alkyl, alkoxy, hydroxyalkyl, alkoxyalkyl, acylamino or amino groups; R4 and R5 may be same or different and independently represent hydrogen, halogen, hydroxy,

cyano, nitro, thio, hydroxylamino, substituted or unsubstituted groups selected from alkyl, alkoxy, acyl, acyloxy, amino, hydrazino, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residues, aminoacyl, carboxyalkyl, carboxyalkenyl, aryl, aryloxy, aralkyl, aralkoxy, alkoxycarbonyl, aryloxycarbonyl, aralkoxycarbonyl, heteroaryl, heteroaryloxy, heteroaralkyl, heteroaralkoxy, heteroarylcarbonyl, heteroaryloxycarbonyl, heteroaralkylcarbonyl heteroaralkoxycarbonyl, heterocyclylcarbonyi, aminocarbonyl, aminocarbonylalkyl, carbonylamino, cycloalkylacylamino, alkylaminoalkoxy, alkylaminoacyl, carboxylic acid or its derivatives, saturated or partially saturated or aromatic single or fused 5 to 7 membered carbocycle ring or saturated or partially saturated or aromatic, single or fused 5 to 7 membered heterocycle ring; R6 represents hydrogen, halogen, hydroxy, amino, cyano, nitro, thio, hydroxylamino or unsubstituted or substituted groups selected from alkyl, alkoxy, carboxyalkyl; the furanone ring may be fused with R wherever possible; R5 and R6 together may represent =C(Ra)(Rb), where Ra and Rb may be same or different and independently represent hydrogen, sub stituted or unsubstituted (C1-C6)alkyl or aryl; =0 or =NR7' where R7 represents hydrogen, aryl or heteroaryl group; X represents oxygen or NR8, where R8 represents hydrogen or substituted or unsubstituted groups selected from (C1-C6)alkyl, aryl, aralkyl, heteroaryl, heteroaralkyl, aralkenoyl, aralkanoyl and m is an integer in the range of 0-2.
The novel derivatives of andrographolide having the general formula (I) form part of our copending WTO/mail box application no. 388/MAS/2000 filed on May 22, 2000,
The compounds of general formula (I) are useful as antiinflammatory, analgesic, antipyretic, antiarthritic, antibacterial, anticancer agents or for treating Alzheimer diseases. The compounds of the present invention are also useful for the treatment of diseases of human or animals such as pain, fever or inflammation. Compounds of formula (I) also inhibit prostanoid-induced smooth muscle contraction by preventing the synthesis of contractile prostanoids and hence may be of use in the treatment of dysmenorrhea, premature labor and asthma. The compounds of the present invention are useful for treatment of pain, fever, and inflammation related to common cold, influenza, viral infections. The compounds of the present invention can be used for the treatment of arthritis such as rheumatoid arthritis, osteoarthritis, gouty arthritis, juvenile arthritis, spondylo arthritis; systemic lupus erythematosus, skin inflammation disorders such as eczema, bums, dermatitis, psoriasis; low back and neck pain, head ache, tooth ache, sprains, strains, myostis, neuralgia, synovitis, bursitis, tendinitis, injuries following

surgical and dental procedures, post-operative inflammation including ophthalmic surgery such as cataract and refractive surgery.
The compounds of general formula (I) are also useful for the treatment of dysmenorrhoea, premature labour, asthma and bronchitis, gastrointestinal conditions such as inflammatory bowel disease, Crohn's disease, gastritis, irritable bowel syndrome, ulcerative colitis, diverticulitis, regional enteritis, peptic ulcers. These compounds may also be useful for treating inflammation in diseases such as vascular diseases, migraine head aches, periarteritis nodosa, thyroiditis, aplastic anemia, Behcat's syndrome, Hodgkin's diseases, scleroderma, myasthenia gravies, sarcoidosis, nephrotic syndrome, Type I diabetes, polymyositis, conjunctivitis, gingivitis, myocardial ischaemia, nephritis, swelling after injury, hypersensitivity and the like. The compounds of the present inventions are useful in the treatment of allergic rhinitis, respiratory distress syndrome, endotoxin shock syndrome, atherosclerosis, and central nervous system damage resulting from stroke, ischaemia and trauma; pulmonary inflammation such as in the case of viral infections and cystic fibrosis; ophthalmic diseases such as retinitis, retinopathy, uveitis, ocular photophobia and acute injury to eye tissues. The compounds of general formula (I) are also useful for treating central nervous system disorders such as cortical dementia (Alzheimer's diseases), useful for treatment of pain not limited to dental pain, muscular pain, pain from cancer, postoperative pain, and useful for the treatment of diseases where NSAIDS are used with the benefit of having significantly less side effects.
The compounds of general formula (I) are cyclooxygenase inhibitors and are therefore useful to treat the cyclooxygenase-mediated diseases. The compounds of formula (I) are also useful for the treatment of mammals not limited to human beings such as horses, dogs, cats, sheep, pigs etc., and also for treating rats, mice, rabbits etc. The compounds of formula (I) may also be used in cotherapies for inflammation, Alzheimer's disease or cancer, in place of, or together with the conventional therapies.
The compounds of the general formula (I) are useful as partial or complete substitute for NSAIDS in compositions or preparations wherein they are presently coadministered with other agents or ingredients.

Background of Invention
Nonsteroidal anti-inflammatory drugs (NSAIDS) are widely used in the treatments of arthritis and pain. These agents act by inhibiting the production of prostaglandin, which plays an important role in the inflammation process. The prostaglandin synthesis is inhibited by blocking the enzyme cyclooxygenase (COX) (Vane J. R. Nature [New Biol.] 1971, 231-232). However, these NSAIDS while reducing the prostaglandin induced inflammation and associated symptoms, have also been found to affect prostaglandin regulated other beneficial processes causing side effects [Allison M. C, et.al, J. Med. 1992, 327, 749]. The side effects showed by NSAIDS are gastrointestinal ulceration and intolerance, blockade of platelet aggregation, inhibition of uterine, motility, inhibition of prostaglandin mediated renal function and hypersensitivity reactions.
Recently, it has been discovered that two isoforms of cyclooxygenase exist enzyme viz., COX-1 and COX-2. While COX-1 is constitutive isoform found in blood vessels, stomach and kidney, COX-2 is induced during inflammation. Therefore, selective inhibition of COX-2 enzyme would be useful in treating inflammation without causing side effects due to inhibition ofCOX-1.
Alternatively Leukotriens also are mediators of inflammation and related disorders. The leukotriens (LTB4, LTC4, LTD4 etc.,) are produced by the 5-lipoxygenase mediated oxidation of arachidonic acid. Hence inhibition of 5-lipoxygenase (5-LO) enzyme would also be useful in treating inflammation and related disorders. It is therefore possible to treat inflammation with agents which can selectively inhibit COX-2 or 5-LO or both without causing the potential side effects caused by chronic treatment with common NSAIDS.
Recently it has been shown that there is increased expression of COX-2 in colon tumors. Therefore, agents that can inhibit COX-2 can also be used in the treatment of cancer.
Studies have shown that the brain tissues of patients of Alzheimer's disease often have high levels of COX-2. This indicates the usefulness of COX-2 inhibitors in the treatment of Alzheimer's disease and in enhancing the memory.
A few heterocyclic compounds, their derivatives, and their analogs have been reported to be useful in the treatment of inflammation. Some of such compounds described in the prior art are outlined below:

(i) International patent application No, WO 97/34882 discloses compounds of general formula (Ila)

wherein R1 is an alkyl or NR4R5 group, wherein R4 and R5 each independently is hydrogen or an alkyl or benzyl group; R is a naphthyl, tetrahydronaphthyl, unsubstituted phenyl or phenyl group, substituted by from 1 to 3 halogen atoms, alkyl, hydroxy, alkoxy or trifiuoromethyl groups and R3 is hydrogen or an alkyl group.
An example of these compounds is shown in formula (IIb)

(ii) DE patent No. 19753463 discloses compounds of formula (IIc)

wherein R1 represents hydrogen, alkoxycarbonyl, carboxy, halogen, alkyl, phenyl or alkanoyl; R2, R3 and R4 represents hydrogen, alkyl, alkoxy or halogen; X represents alkyl or NH2. An example of these compounds is shown in formula (IId)


C(R5)(R6)-0-(C1-C4)alkyl and -(C1-C6)alkyl-C02-R5 mono, di or tri substituted heteroaryl wherein the heteroaryl is a monocyclic aromatic ring of 5 atoms, said ring having one hetero atom which is S, O or N and optionally 1, 2, 3 or 4 additional N atoms, said substituents are selected from the group consisting of hydrogen, halogen including fluoro, chloro, bromo and

iodo, (C1-C6)alkyl, (C1-C6)alkoxy, (CrC6)alkylthio, CN, CF3, N3, -C(R5)(R6)-OH and , -C(R5)(R6)-0-(C1-C4)alkyl; R5 is selected from the group consisting of hydrogen, CF3, CN, (Ci-C6)alkyl, hydroxy(C1-C6)alkyl, -C(0)-(C1-C6)alkyl and optionally substituted -(C1-C5)alkyl-Q, -(C1-C3)alkyl-0-(C1-C3)alkyl-Q, -(C1-C3)aIkyl-S-(C1-C3)alkyl-Q, -(C1-C6)alkyl-O-Q, or -(C,-C5)alkyl-S-Q, wherein the substituents resides on the alkyl and the substituent is (C1-C3)alkyl; or R3 represents -Q; R and R4 are each and independently selected from the group consisting of hydrogen, CF3, CN, (C1-C6)alkyl, -Q, -0-Q, -S-Q, and optionally substituted (C1-C5)alkyl-Q, -0-(Ci-C5)alkyl-Q , -S-(C,-C5)alkyl-Q, -(C1-C3)alkyl-0-(CrC3)alkyl-Q, -(C,-C3)alkyl-S-(Ci-C3)alkyl-Q, -(Ci-C5)aIkyl-0-Q, or -(C|-C5)alkyl-S-Q, wherein the substituents resides on the alkyl and the substituent is (C1-C3)alkyl; and R5, R5, R6, R7 and R8 are each independently selected from the group consisting of hydrogen, (C1-C6)alkyl or R5, R5, R6, R7 and R8 together with the carbon to which they are attached form a monocyclic saturated carbon ring of 3, 4, 5, 6, or 7 atoms. Q is CO2H, C02-(C1-C4)alkyl, tetrazolyl-5-yl, C(R7)(R8)(OH), or C(R7)(R8)(0-(CrC4)alkyl; provided that when X-Y-Z is S-CR4-CR4, then R4 and R4 are other than CF3-

wherein A is a 5 or 6 membered ring substituent selected from partially unsaturated heterocycle and carbocyclic rings, A may be optionally substituted with a radical selected from acyl, halogen, alkyl, haloalkyl, cyano, nitro, carboxyl, alkoxy, 0x0, aminocarbonyl, alkoxycarbonyl, carboxyalkyl, cyanoalkyl and hydroxyalkyl; Y is a radical selected from oxy, thio, sulfmyl,

sulfonyl, alkyl, alkenyl, alkynyl, alkyloxy, alkylthio, alkylcarbonyl, cycloalkyl, aryl, haloalkyl,
hydroxyalkyl, hydroxyalkyloxy, hydroxyalkyloxyalkyl, hydroxy alkylthio,
hydroxyalkylthioalkyl, oximinoalkoxy, oximinoalkoxyalkyl, (alkyl)oximinoalkoxy,
(alkyl)oximin6aIkoxyalkyl, oximinoalkylthio, oximinoalkylthioalkyi, (alkyl)oximinoalkylthio,
(alkyl)oximinoalkylthioalkyl, carbonylalkyloxy, carbonylalkyloxyalkyl, carbonylakylthio,
carbonylalkylthioalkyl, heterlcyclo, cycloalkenyl, aralkyl, heterocycloalkyl, acyl,
alkylthioalkyl, alkyloxyalkyl, alkenylthio, alkynylthio, alkenyloxy, alkynyloxy,
alkenylthioalkyl, alkenyloxyalkyl, alkynyloxyalkyl, arylcarbonyl, aralkylcarbonyl, aralkenyl,
alkylarylalkynyloxy, alkylarylalkenyloxy, alkylarylalkynylthio, alkylarylalkenylthio,
haloalkyicarbonyl, alkoxyalkyl, alkylaminocarbonylalkyl, heteroaralkoxyalkyl,
heteroaryloxyalkyl, heteroarylthioalkyl, heteroaralkylthioalkyl, heteroaralkoxy,
hetercaralkylthio, heteroaryloxy, heteroarylthio, arylthioalkyl, aryloxyalkyl, haloaryloxyalkyi,
aralkylthioalkyl, aralkoxyalkyl, alkoxyaralkoxyalkyl, alkoxycarbonylalkyl,
alkoxycarbonylcyanoalkenyl, aminocarbonylalkyl, N-alkylaminocarbonyl, N-
arylaminocarbonyl, N,N-dialkylaminocarbonyl, N-alkyl-N-arylaminocarbonyl,
cycloalkylaminocarbonyl, heterocycloaminocarbonyl, carboxyalkylaminocarbonyl,
alkylcarbonylalkyl, aralkoxycarbonylalkylaminocarbonyl, haloaralkyl, carboxyhaloalkyl, alkoxycarbonylhaloalkyl, aminocarbonylhaloalkyl, alkylaminocarbonylhaloalkyl, N-alkylamino, N,N-dialkylamino, N-arylamino, N-aralkylamino, N-alkyl-N-aralkylamino, N-alkyl-N-arylamino, aminoalkyl, N-alkylaminoalkyl, N,N-dialkylaminoalkyl, N-arylaminoalkyl, N-aralkylaminoalkyl, N-alkyl-N-aralkylaminoalkyl;. N-alkyl-N-arylaminoalkyl, aminoalkoxy, aminoalkoxyalkyl, amino alkylthio, aminoalkylthioalkyl, cycloalkyloxy, cycloalkylalkyloxy, cycloalkylthio, cycloalkylalkylthio, aryloxy, aralkoxy, arylthio, aralkylthio, arlkylsulfmyl, alkylsulfonyl aminosulfonyl, N-alkylaminosulfonyl, N-arylaminosulfonyl, arylsulfonyl, N,N-dialkylaminosulfonyl, N-alky-N-araylaminosulfonyl, or Y represents following groups


Ar is selected from aryl and heteroaryl, Ar may be optionally substituted with one or two substituents selected from halogen, hydroxy], mercapto, amino, nitro, cyano, carbamoyl, alkyl, alkenyloxy, alkoxy, alkylthio, alkylsulfonyl, alkylsulfonyl, alkylamino, dialkylamino, haloalkyl, alkoxycarbonyl, N-alkylcarbamoyl, N,N-dialkylcarbamoyl, alkanoylamino, cyanoalkoxy, carbamoylalkoxy, alkoxycarbonylalkoxy, and

where R1 is one or more substituents selected from heterocycle, cycloalkyl, cycloalkenyl, and aryl, R1 may be optionally substituted at a substitutable position with one or more radicals selected from alkyl, haloalkyl, cyano, carboxyl, alkoxycarbonyl, hydroxyl, hydroxyalkyl, haloalkoxy, amino, alkylamino, arylamino, nitro, alkoxyalkyl, alkylsulfmyl, halogen, alkoxy and alkythio; R2 is selected from alkyl and amino; wherein R3 and R4 together form a group of the formula -B-X-B1 which together with the carbon atom to which B and B1 are attached defines a ring having 6 ring atoms, wherein B and B1 which may be the same or different, each is alkylene and X is oxy, and which ring may bear one, two or three substituents, which may be the same or different selected from hydroxyl, alkyl, alkoxy, alkenyloxy and alkynyloxy; wherein R5 is selected from hydroxyl, alkoxy, alkylcarbonyloxy, arylcarbonyloxy, alkoxycarbonyl, acyl, and cyano; wherein R6 is selected from hydrido, alkyl, aryl, and aralkyl; wherein R is selected from alkyl, alkoxy, alkenyl, and alkynyl; wherein R is oximino optionally substituted with alkyl; wherein n is 0 or 1; provided Ar is substituted with



where R3 , R4 R58 , R and n are as defined above
An example of these compounds is shown in formula (Ilh)

wherein R1 is haloalkyl; R2 is aryl optionally substituted at a substitutable position with one or more radicals independently selected from alkysulfmyl, alkyl, cyano, carboxyl, alkoxycarbonyl, haloalkyl, hydroxyl, hydroxyalkyl, haloalkyl, amino, alkylamino, arylamino, mitro, halogen, alkoxy and alkylthio; R3 is aryl substituted at a substitutable position with a radical selected from alkylsulfonyl and sulfamyl and R is selected from halogen, alkoxy, and alkynyloxy. An example of these compounds is shown in formula (IIj)

(vi) German patent DE19533643 discloses compounds of formula (Ilk)


wherein A is 0, S or NH; R1 is optionally substituted cycloalkyl, aryl or heteroaryl; R2 is hydrogen, optionally substituted alky], aralkyl, aryl, heteroaryl, or (CH2)n-X; Z is CH2, CH2CH2, CH2CH2CH2, CH2CH=CH, CH2CO, NHCO, NHCH2, N=CH, NHCH, CH2CH2NH, CH=CH, C=0, S(0)m or optionally substituted NH; m is 0-2; n is 0-8; X is halogen, NO2, optionally substituted OH, COH, COOH, OCOOH, CONHOH, CONH2, SH, S(0)H, SO2H, NH2, NHCOH or NHSO2H or CN; R6 is optionally substituted (C1-C4)alkyL An example of these compounds is shown in formula (III)

(vii) International patent application WO 95/15316 discloses compounds of formula (Ilm)
wherein R2 is selected from hydrido, alkyl, haloalkyl, alkoxycarbonyl, cyano, cyanoalkyl,
carboxy, aminocarbonyl, alkylaminocarbonyl, cycloalkylaminocarbonyl, arylaminocarbonyl,
carboxyalkylaminocarbonyl, carboxyalkyl, aralkoxycarbonylalkylaminocarbonyl,
aminocarbonylalkyl, alkoxycarbonyl, cyanoalkenyl and hydroxyalkyl; wherein R3 is selected from hydrido, alkyl, cyano, hydroxyalkyl, cycloalkyl, alkylsulfonyl, and halogen; R is selected from aralkenyl, aryl, cycloalkyl, cycloalkenyl and heterlcyclic, R4 is optionally substituted at a substitutable position with one or more radicals selected from halogen, alkylthio, alkylsulfonyl, cyano, nitro, haloalkyl, alkyl, hydroxyl, alkenyl, hydroxyalkyl, carboxyl, cycloalkyl, alkylamino, dialkylamino, alkoxycarbonyl, aminocarbonyl, alkoxy, haloalkoxy, sulfamyl,

. - heterocyclic and amino; provided R2 and R3 are not both hydrido; further provided that R2 is not carboxyl, or methyl when R3 is hydrido and when R4 is phenyl; further provided that R4 is not triazolyl when R2 is methyl; further provided that R4 is not aralkenyl when R2 is carboxyl, aminocarbonyl or ethoxycarbonyl; further provided that R4 is not phenyl when R2 is methyl and R is carboxyl; and further provided that R4 is not unsubstituted thienyl when R2 is trifluoromethyl.
An example of these compounds is shown in formula (IIn)

(viii) International patent application WO 96/19462 discloses compounds of formula (IIo)
wherein one of R, R1 is methylsulfonylphenyl, aminosulfonylphenyl or alkylaminosulfonylphenyl and the other is 5-7carbon cycloalkyl optionally substituted by alkyl, thienyl or furyl optionally substituted by alkl or halogen; R is lower alkyl. An example of these compounds is shown in formula (Up)


Objective of the Invention
With an objective of preparing novel compounds for the treatment and / or prophylaxis of diseases or conditions related to cyclooxygenase, more particularly COX-2 and other related diseases such as pain, fever or inflammation, to inhibit prostanoid-induced smooth muscle contraction, to treat Alzheimer disease, colorectal cancer, for the treatment of pain, fever, and inflammation related to common cold, influenza, viral infections, for the treatment of arthritis such as rheumatoid arthritis, osteoarthritis, gouty arthritis, juvenile arthritis, spondylo arthritis; systemic lupus erythematosus, skin inflammation disorders such as eczema, bums, dermatitis, psoriasis; low back and neck pain, dysmenorrhoea, head ache, tooth ache, sprains, strains, . myostis, neuralgia, synovitis, bursitis, tendinitis, injuries following surgical and dental procedures, post-operative inflammation including ophthalmic surgery such as cataract and refractive surgery, with better efficacy, potency and lower toxicity, we focussed our research to develop new compounds effective in the treatment of above mentioned diseases. Effort in this direction has led to the development of compounds having general formula (I).
The main objective of the present invention is therefore, to provide novel compounds 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.
The main objective of the present invention is to produce a process for the preparation of novel compounds and their derivatives of the formula (I) as defined above, their analogs, their tautomeric forms, their stereoisomers, their regioisomers, their polymorphs, their pharmaceutically acceptable salts and their pharmaceutically acceptable solvates.
The present invention also provides a process for the preparation of novel intermediates of formulae (I-l), (1-3), (1-5), (1-7), (II-l), (II-2) and (II-4).

Summary of the invention
The present invention relates to a process for the preparation of novel compound having the general formula (I),

where in R1 represents amino or substituted or unsubstituted groups selected from alkyl, alkylamino, acylamino, cycloalkyl, cyclicamino, carboethoxycarbonylalkyl, hydrazine, hydrazido, aminoacid residue, aryl, heteroaryl or -N=CR(NR)2 where R represents hydrogen or lower alkyl group; R2 represents halogen, hydroxy, cyano, nitro, azido, formyl, oximealkyl, thio or substituted or unsubstituted groups selected from amino, alkyl, alkoxy, hydrazino, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residue, aminoacid residuealkyl, acyl, carbonyloxyalkyl, haloalkyl, aminoalkyl, haloalkoxy, hydroxyalkyl, alkoxyalkyl, thioalkyl, alkylthio, alkylsulfinyl, alkylsulfonyl, aryl, aralkyl, aryloxy, aralkoxy, aryloxyalkyl aralkoxyalkyl, carboxamidoalkyl, carbonylaminoalkyl groups or when the groups -S(=0)m-R' and R2 are present on adjacent carbon atoms, R1 and R2 together with atoms to which they are attached may also form a substituted or unsubstituted 5-7 membered cyclic structure containing carbon atoms, a sulfur atom and may optionally contain one or two heteroatoms selected from O, S or N; R3 represents hydrogen, halogen atom, hydroxy, nitro, cyano, azido or substituted or unsubstituted groups selected from hydrazino, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residues, alkyl, alkoxy, hydroxyalkyl, alkoxyalkyl, acylamino or amino groups; R4 and R5 may be same or different and independently represent hydrogen, halogen, hydroxy, cyano, nitro, thio, hydroxylamino, substituted or unsubstituted groups selected from alkyl, alkoxy, acyl, acyloxy, amino, hydrazino, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residues, aminoacyl, carboxyalkyl, carboxyalkenyl, aryl, aryloxy, aralkyl, aralkoxy, alkoxycarbonyl, aryloxycarbonyl, aralkoxycarbonyl, heteroaryl, heteroaryloxy, heteroaralkyl, heteroaralkoxy, heteroarylcarbonyl, heteroaryloxycarbonyl, heteroaralkylcarbonyl, heteroaralkoxycarbonyl, heterocyclylcarbonyl, aminocarbonyl, aminocarbonylalkyl, carbonylamino, cycloalkylacylamino, alkylaminoalkoxy, alkylaminoacyl, carboxylic acid or its

derivatives, saturated or partially saturated or aromatic single or fused 5 to 7 membered carbocycle ring or saturated or partially saturated or aromatic, single or fused 5 to 7 membered heterocycle ring; R6 represents hydrogen, halogen, hydroxy, amino, cyano, nitro, thio, hydroxylamino or unsubstituted or substituted groups selected from alkyl, alkoxy, carboxyalkyl; the furanone ring may be fused with R4 wherever possible; R5 and R6 together may represent =C(Ra)(Rb), where Ra and Rb may be same or different and independently represent hydrogen, (C1-C6)alkyl or aryl; =0 or =NR7 where R7 represents hydrogen, aryl or
heteroaryl group; X represents oxygen or NR , where R represents hydrogen or substituted or unsubstituted groups selected from (C1-C6)alkyl, aryl, aralkyl, heteroaryl, heteroaralkyl, aralkenoyl, aralkanoyl and m is an integer in the range of 0-2.
Detailed Description of the Invention
Suitable groups represented by R1 may be selected from amino, substituted or unsubstituted linear or branched (C1-C6)alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl, n-pentyl, isopentyl, hexyl and the like; (C1-C6)alkylamino group such as methylamino, ethylamino, propylamine, butylamino, pentylamino, hexylamino and the like, which may be substituted; acylamino groups such as NHCOCH3, NHCOC2H5, NHCOC3H7, NHCOC6H5 and the like, which may be substituted; (C3-C8)cycloalkyl group such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and the like, which may be substituted; cyclicamino group such as aziridine, pyrrolidine, piperidine and the like, the cyclicamino group may be substituted; carboethoxycarbonyl(C1-C6)alkyl group such as carboethoxycarbonylmethyl, carboethoxycarbonylethyl, carboethoxycarbonylpropyl and the like, the carboethoxycarbonyl(C1-C6)alkyl group may be substituted; hydrazine, which may be substituted; hydrazido, which may be substituted; aminoacid residues, wherein the aminoacid is selected from glycine, alanine, phenylalanine, lysine and the like, which may be substituted; aryl group such as phenyl, naphthyl and the like, the aryl group may be substituted; heteroaryl group such as pyrrole, furan, pyridine, thiophene and the like, the heteroaryl group may be substituted; or -N-CR(NR)2.
The suitable groups represented by R are selected from hydrogen or (C1-C6)alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl and the like.

Suitable groups represented by R1 may be selected halogen atom such as chlorine, fluorine, bromine or iodine; hydroxy, cyano, nitro, azido, formyl, oxime(C1-C6)alkyl groups such as oximemethyl, oximeethyl, oximepropyl and the like; thio, amino group, which may be substituted; substituted or unsubstituted linear or branched (C1-C6)alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl, n-pentyl, isopentyl, hexyl and the like; (C]-C6)alkoxy such as methoxy, ethoxy, propyloxy, butyloxy, iso-propyloxy and the like, which may be substituted; hydrazino, which may be substituted; hydrazino(C!-C6)alkyl group such as hydrazinomethyl, hydrazinoethyl, hydrazinopropyl and the like, which may be substituted; hydrazido, which may be substituted; hydrazido(C1-C6)alkyl such as hydrazidomethyl, hydrazi do ethyl, hydrazidopropyl and the like, which may be substituted; aminoacid residues, wherein the aminoacid is selected from glycine, alanine, phenylalanine, lysine and the like, which may be substituted; aminoacid residue(C1-C6)alkyl wherein the aminoacid is as defined above, which may be substituted; acyl group such as acetyl, propanoyl, benzoyl and the like, which may be substituted; carbonyloxy(CrC6)alkyl group such as carbonyloxymethyl, carbonyloxyethyl, carbonyloxypropyl and the like, which may be substituted; halo(C1-C6)alkyl such as chloromethyl, bromoethyl, chloropropyl, chloroisopropyl and the like, which may be substituted; amino(CrC6)alkyl such as aminomethyl, aminoethyl, aminopropyl, aminoisopropyl and the like, which may be substituted; halo(C|-C6)alkoxy such as chloromethoxy, bromethoxy, chloropropoxy, bromopropoxy and the like, which may be substituted; hydroxy(C1-C6)alkyl such as hydroxymethyl, hydroxyethyl, hydroxypropyl, hydroxyisopropyl and the like, which may be substituted; alkoxy(C1-C6)alkyl group such as methoxymethyl, ethoxymethyl, methoxyethyl, ethoxyethyl and the like, which may be substituted; thio(C1-C6)alkyl such as thiomethyl, thioethyl, thiopropyl, thioisopropyl and the like, which may be substituted; (C|-C6)alkylthio such as methylthio, ethylthio, propylthio, isopropylthio and the like, which may be substituted; (C1-C6)alkylsulfinyl such as methylsulfinyl, ethylsulfmyl, n-propylsulfmyl, isopropysulfinyl, butylsulfmyl and the like, the (C!-C6)alkylsulfinyl group may be substituted; (C1-C6)alkylsulfonyl such as methylsulfonyl, ethylsulfonyl, n-propylsulfonyl, isopropysulfonyl, butylsulfonyl and the like, the (C1-C6)alkylsulfonyl group may be substituted; aryl group such as phenyl, naphthyl and the like, the aryl group may be substituted; aralkyl such as benzyl, phenethyl, C6H5CH2CH2CH2, naphthylmethyl and the like, the aralkyl group may be substituted; aryloxy group such as phenoxy, naphthyloxy and the like, the aryloxy group may

be substituted; aralkoxy group such as benzyloxy, phenethyloxy, naphthylmethyloxy, phenylpropyloxy and the like, which may be substituted; aryloxyalkyl group such as C6H5OCH2, C6H5OCH2CH2, naphthyloxymethyl and the like, which may be substituted; aralkoxyalkyl group such as C6H5CH2OCH2, C6H5CH2OCH2CH2 and the like, which may be substituted; carboxamido(C1-C6)alkyl such as carboxamidomethyl, carboxamidoethyl, carboxamidopropyl and the like, carboxamido(C1-C6)alkyl group may be subtituted; carbonylamino(C1-C6)alkyl group such as carbonylaminomethyl carbonylaminoethyl, carbonylaminopropyl and the like, the carbonylamino(C|-C6)alkyl may be substituted.
When R1 and R2 together form a cyclic structure, R1 and R2 together represent substituted or unsubstituted -NH-C(=0)-(CH2)TT, -CH2-(CH2)n-, -(CH2)n-C(=0)-, -CH2-C(=0)-CH2-, -NH.(CH2)n-, -NH-C(=0)-, -NH-(CH2)n-C(-0)-, -(CH2)n-C(=0)-NH-, -NH-(CH2)n-0-, -NH-(CH2)n-S-, -CH2-(CH2)n-0-, -CH2-(CH2)n-S-, where n is an integer in the range of 1-2,
The substituents on R and R may be selected from hydroxy, linear or branched (Cp C6)alkyl, (C1-C6)alkoxy, aryl, aralkyl, aralkoxy, acyl, heteroaryl such as pyridyl, furyl, thiophenyl, oxazolyl and the like; heteroaralkyl such as pyridylmethyl, pyridylethyl, furanmethyl, furanethyl and the like; heterocyclyl such as morpholinyl, piperidinyl, piperzinyl, pyrrolidinyl, dihydro-3-oxo-l,l-dioxo-benzo[b]isothiazolyl, benzoisothiazolyl, benzothiazolyl and the like; sulfonyl, (C1-C6)alkylsulfinyl, arylsulfinyl such as phenylsulfonyl, naphthylsulfonyl and the like; (C1-C6)alkylsulfonyl, arylsulfonyl such as phenylsulfmyl, naphthylsulfinyl and the like; wherein the alkyl and aryl moieties may be substituted with hydroxy, halogen atom such as chlorine, fluorine, bromine or iodine; nitro or amino groups.
Suitable groups represented by R3 may be selected from hydrogen, halogen atom such as chlorine, fluorine, bromine or iodine; hydroxy, nitro, cyano, azido, hydrazino, which may be substituted; hydrazino(C!-C6)alkyl groups such as hydrazinomethyl, hydrazinoethyl, hydrazinopropyl and the like, which may be substituted; hydrazido, which may be substituted; hydrazido(C1-C6)alkyl such as hydrazidomethyl, hydrazidoethyl, hydrazidopropyl and the like, which may be substituted; aminoacid residues, wherein the aminoacid is selected from glycine, alanine, phenylalanine, lysine and the like, which may be substituted; linear or branched (C1-C6)alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl, n-pentyl, isopentyl, hexyl and the like, which may be substituted; (C1-C6)alkoxy such as methoxy, ethoxy, propyloxy, butyloxy, iso-propyloxy and the like, which may be substituted;

hydroxy(C1-C6)alkyl such as hydroxymethyl, hydroxyethyl, hydroxypropyl, hydroxyisopropyl and the like, which may be substituted; (C1-C6)alkoxy(CrC6)alkyl group such as methoxymethyl, ethoxymethyl, methoxyethyl, ethoxypropyl and the like, which may be substituted; acylamino groups such as NHCOCH3, NHCOC2H5, NHCOC3H7, NHCOC6H5 and the like, which may be substituted; amino group, which may be substituted.
Suitable groups represented by R4 and R5 may be selected from hydrogen, halogen atom such as fluorine, chlorine, bromine, or iodine; hydroxy, cyano, nitro, thio, hydroxylamino, substituted or unsubstituted linear or branched (C1-C6)alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl, n-pentyl, isopentyl, hexyl and the like; (C1-C6)alkoxy such as methoxy, ethoxy, propoxy, isopropoxy, butoxy and the like, the (C1-C6)alkoxy groups may be substituted; acyl group such as formyl, acetyl, propanoyl, benzoyl and the like; the acyl group may be substituted; acyloxy group such as OCOMe, OCOEt, OCOPh and the like, the acyloxy group may be substituted; amino group, which may be substituted; hydrazino, which may be substituted; hydrazino(C1-C6)alkyl groups such as hydrazinomethyl, hydrazino ethyl, hydrazinopropyl and the like, which may be substituted; hydrazido, which may be substituted; hydrazido(Ci-C5)alkyl such as hydrazidomethyl, hydrazidoethyl, hydrazidopropyl and the like, which may be substituted; aminoacid residues, wherein the aminoacid is selected from glycine, alanine, phenylalanine, lysine and the like, which may be substituted; aminoacyl such as aminoacetyl, aminopropanoyl, aminobutanoyl and the like, which may be substituted; carboxy(C1-C6)alkyl such as carboxymethoxy, carboxyethyl, carboxypropyl and the like, which may be substituted; carboxy(C2-C6)alkenyl such as carboxyethenyl, carboxypropenyl, carboxybutenyl and the like, which may be substituted; aryl group such as phenyl, naphthyl and the like, the aryl group 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; aralkoxy group such as benzyloxy, phenethyloxy, naphthylmethyloxy, phenylpropyloxy and the like, which may be substituted; (C1-C6)alkoxycarbonyl such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl and the like, the (C1-C6)alkoxycarbonyl may be substituted; aryloxycarbonyl such as phenoxycarbonyl, naphthyloxycarbonyl and the like, which may be substituted; aralkoxycarbonyl group such as benzyloxycarbonyl, phenethyloxycarbonyl, naphthylmethoxycarbonyl and the like, which may

be substituted; aminocarbonyl, which may be substituted; carbonylamino, which may be
substituted; aminocarbonyl(C1-C6)alkyl such as aminocarbonylmethyl, aminocarbonylethyl,
aminocarbonylpropyl and the like, the aminocarbonyl(C1-C6)alkyl may be substituted; (d-
C6)alkylamino(C1-C6)alkoxy groups such as methylaminomethoxy, ethylaminoethoxy,
methylaminoethoxy, ethylaminomethoxy, propylaminoethoxy and the like, the (Ci-
C6)alkylamino(C1-C6)alkoxy group may be substituted; (C1-C6)alkylaminoacyl groups such as
methylaminoacetyl, ethylaminopropanoyl, methylaminopropanoyl, ethylaminoacetyl and the
like, the (C1-C6)alkylaminoacyl group may be substituted; (C3-C8)cycloalkylacylamino such as
cyclopropylacylamino, cyclobutylacylamino, cyclobutylacylamino and the like, (C3-
C8)cycloalkylaminoacyl may be substituted; substituted or unsubstituted carbocychc groups
such as phenyl, indenyl, indanyl, dihydronaphthyl, tetrahydronaphthyl, naphthyl, cyclobutyl
cyclopentyl, cyclohexyl, cycloheptyl, cyclobutenyl, cyclopentenyl, cyclohexenyl and the like;
heteroaryl and heterocyclyl groups such as pyrrolyl, pyrrolidinyl, furyl, dihydrofuryl,
tetrahydrofuryl, furanonyl, benzofuryl, dihydrobenzo furyl, benzofuranonyl, thienyl,
benzotheinyl, dihydrobenzotheinyl, thiazolyl, benzothiazolyl, imidazolyl, benzimidazolyl,
pyrazolyl, oxazolyl, isooxazolyl, benzoxazolyl, isothiazolyl, oxadiazolyl, thiadiazolyl, triazolyl,
tetrazolyl, indolyl, azaindolyl, indolinyl, dihydroindolinyl, dihydroindolinonyl, azaindolinyl
pyranyl, benzopyranyl, dihydrobenzopyranyl, tetrahydrobenzopyranyl, diazinyl, triazinyl,
tetrazinyl, pyridyl, piperidinyl, piperidinonyl, pyridazinyl, pyrazinyl, piperazinyl, morpholinyl,
quinolinyl, dihydroquinolinyl, oxazinyl, benzoxazinyl, dihydrobenzoxazinyl, thiazinyl,
benzothiazinyl, dihydrobenzothiazinyl, quinazolinyl, dihydroquinazolinyl, phthalazinyl,
dihydrophthalazinyl, quinaoxalinyl, dihydrobenzothienyl-1 -oxide, dihydrobenzothienyl-1,1-
dioxide, which may be substituted; heterocyclylcarbonyl groups such as pyrrolidinylcarbonyl,
morpholinylcarbonyl, piperidinylcarbonyl, piperazinylcarbonyl and the like, the heterocyclyl
group may be substituted; heteroaryl carbonyl group such as pyridylcarbonyl, thienylcarbonyl,
furylcarbonyl, pyrrolylcarbonyl, oxazolylcarbonyl, thiazolylcarbonyl, oxadiazolylcarbonyl,
thiadiazolylcarbonyl, tetrazolylcarbonyl and the like, the heteroaryl group may be substituted;
heteroaryloxy, heteroaralkyl such as pyridylmethyl, pyridylethyl, furanmethyl, furanethyl and
the like; heteroaralkoxy, heteroaralkylcarbonyl, heteroaryloxycarbonyl,
heteroaralkoxycarbonyl, wherein the heteroaryl and heteroaralkyl moieties are as defined

above, which may be substituted; carboxyhc acid or its derivatives such as amides, hke CONH2, CONHMe, C0NMe2, CONHEt, C0NEt2, CONHPh and the hke;
Suitable substituents on the groups represented by R4 and R5 are selected from halogen
atom such as fluorine, chlorine, bromine, or iodine; hydroxy, cyano, nitro, optionally
halogenated (C1-C6)alkyl, optionally halogenated (C1-C3)alkoxy, acyl, amino, acylamino, (C3-
C8)cycloalkyl, (C3-C8)cycloalkoxy, aryl, aryloxy, aralkyl, aralkoxy, heteroaryl, heterocyclyl
such as morpholinyl, piperidinyl, piperzinyl, pyrrolidinyl and the like; heteroaryloxy,
heteroaralkyl, heteroaralkoxy, heteroaryloxycarbonyl, heteroaralkoxycarbonyl,
heteroaryloxycarbonylamino, heteroaralkoxycarbonylamino, acyloxy, (C1-C6)alkoxycarbonyl aryloxycarbonyl, aralkoxycarbonyl, mono(CrC6)alkylamino such as methylamino, ethylamino, isopropylamino and like, (C1-C6)dialkylamino such as dimethylamino, methylethylamino and the Ike; arylamino such as phenylamino, naphthylamino and the like; aralkylamino such as benzylamino, phenethylamino and the Ike; amino(C1-C6)alkyl such as aminomethyl, aminoethyl, aminoisopropyl and the like; hydroxy(C1-C6)alkyl, (C1-C6)alkoxy(C1-C6)alkyl such as methoxymethyl, methoxyethyl, ethoxypropyl and the like; aryloxy(C1-C6)alkyl such as phenyloxymethyl, phenyloxy ethyl, naphthyloxy methyl, naphthyloxyethyl and the like; aralkoxy(C1-C6)alkyl such as bezyloxymethyl, benzyloxymethyl, phenethoxymethyl, phenethoxyethyl and the like; (CrC6)alkoxycarbonylamino such as methoxycarbonylamino, ethoxycarbonylamino, propoxycarbonylamino and the like; aryloxycarbonylamino such as phenyloxycarbonylamino, naphthyloxycarbonylamino, aralkoxycarbonylamino such as benzyloxycarbonylamino, phenethyloxycarbonylamino and the like; thio, thio(C1-C6)alkyl, (Cp C6)alkylthio, (C]-C6)alkylsulfinyl such as methylsulfmyi, ethylsulfmyl, n-propylsulfmyl, isopropysulfinyl, butylsulfmyl and the like; (C1-C6)alkylsulfonyl methylsulfonyl, ethylsulfonyl, n-propylsulfonyl, isopropysulfonyl, butylsulfonyl and the like; sulfonic acid or its derivatives such as SO2NH2, S02NHMe, S02NMe2, S02NHEt, S02NEt2 and the like; or carboxyhc acid or its derivatives such as amides, like CONH2, CONHMe, C0NMe2, CONHEt, C0NEt2, CONHPh and the like; The substituents on the groups are as defined for R4 and R5
Suitable groups represented by R6 are selected from hydrogen, halogen atom such as fluorine, chlorine, bromine, or iodine; hydroxy, amino, cyano, nitro, thio, hydroxylamino, linear or branched (C1-C6)alkyl group, such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, t-butyl, n-pentyl, iso-pentyl, hexyl and the like, the (C1-C6)alkyl group may be

substituted; (C1-C6)alkoxy such as methoxy, ethoxy, propyloxy, butyloxy, iso-propyloxy and the like, the" (C1-C6)alkoxy group may be substituted; carboxy(C1-C6)alkyl such as carboxymethyl, carboxyethyl, carboxypropyl and the like, the carboxy(C1-C6)alkyI may be substituted.
The suitable groups represented by Ra and Rb are selected from hydrogen or (C1-C6)alkyl group such as methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl and the like; aryl group such as phenyl, naphthyl and the like.
The suitable groups represented by R7 are selected from hydrogen, aryl group such as phenyl, naphthyl and the like; heteroaryl group such as pyridyl, furyl, thiophenyl, benzothiazoyl, purinyl, benzimidazoyl, pyrimidinyl, tetrazolyl and the like;
Suitable ring structures formed by R4 fused with furanone may be selected from
2,3a,4,5-tetrahydronaphtho[2,l-b]furan-2-one; 4-thioxo-2,3a,4,5-tetrahydronaphtho[2,l-
b]furan-2-one; 4-imino-2,3a,4,5-tetrahydronaphtho[2,l-b]furan-2-one; 3a,4,5,6-
tetrahydronaphtho[2,l-b]furan-2-one; 2,3a-dihydronaphtho[2,l-b]furanone; 2,3a,4,5-
tetrahydronaphtho[2,l-b]furan-2,4-dione; 2,3a-dihydronaphtho[2,l-b]furan-2,4-dione; 3a,4-
dihydro-2H-furo[2,3-c]chromene-2-one; 3a,4-dihydrO'2H-furo[2,3-c]chromene-2,4-dione;
2,3a,4,5-tetrahydro-2H-furo[2,3-c]chromene-2-one; 4-thioxo-2,3a,4,5-tetrahydro-2H-furo[2,3-
c]chromene-2-one; 4-imino-2,3a,4,5-tetrahydro-2H-furo[2,3-c]chromene-2-one; 2,3a,4,5-
tetrahydro-2H-furo[2,3-c]chromene-2,4-dione; 2,3a,4,5-tetrahydrofuro[2,3-c]quinolin-2-one;
2,3a,4,5-tetrahydrofuro[2,3-c]quinolin-2,4-dione; 8,8a-dihydro-2H-indeno[2,l-b]furan-2-
one; 4-thioxo-8,8a-dihydro-2H-indeno[2,l-b]furan-2-one; 4-imino-8,8a-dihydro-2H-
indeno[2,l-b]furan-2-one; 2,8a-dihydrobenzo[4,5]thieno[2,3-b]furan-2-one; 2,8a-
dihydrobenzo[b]furo[3,2-d]furan-2-one; 8,8a-dihydro-2H-furo[2,3-b]indol-2-one; 8,8a-dihydro-2H-indeno[2,l-b]furan-2-one; 3a,4,5,6-tetrahydro-2H-benzo[3,4]cyclohepta[b]furan-2-one; 3a,4,5,8-tetrahydro-2H-indeno[5,4-b]furan-2-one; 4,5,5a,7-tetrahydro-lH-furo[2,3-g]indol-7-one; 4,5,5a,7-tetrahydrothieno[2',3' : 3,4]benzo[b]furan-7-one; 4,5,5a,7-tetrahydrofuro[2',3' : 3,4]benzo[b]furan-7-one.
O Q
The suitable groups represented by X are selected from oxygen or NR where R represents hydrogen or linear or branched (C1-C6)alkyl group such as methyl, ethyl, n-propyl isopropyl, n-butyl, iso-butyl, t-butyl, n-pentyl, isopentyl, hexyl and the like, the (C1-C6)alkyl group may be substituted; aryl group such as phenyl, naphthyl and the like, the aryl group may

be substituted; aralkyl such as benzyl, phenethyl and the like, the aralkyl group may be substituted; heteroaryl group such as pyridyl, furyl, thiophenyl, benzothiazoyl, purinyl, benzimidazoyi, pyrimidinyl, tetrazolyl and the like, the heteroaryl group may be substituted; heteroaralkyl group such as pyridylmethyl, pyidylethyl, furanmethyl, furanethyl and the like, the heteroaralkyl group may be substituted; aralkenoyl group such as phenylpropenoyl, phenylbutenoyl, phenylpentenoyl and the like, the aralkenoyl group may be substituted; aralkanoyl group such as phenylpropanoyl, phenylbutanoyl, phenylpentanoyl and the like, the aralkanoyl group may be substituted.
The substituents on R3, R6 and R8 may be selected from nitro, halogen atom such as fluorine, chlorine, bromine or iodine; amino, hydroxy, thio or cyano groups.
Pharmaceutically acceptable salts forming part of this invention include salts derived
from inorganic bases such as Li, Na, K, Ca, Mg, Fe, Cu, Zn, Mn; salts of organic bases such as
N,N'-diacetylethylenediamine, betaine, caffeine, 2-diethylaminoethanol, 2-
dimethylaminoethanol, N-ethylmorpholine, N-ethylpiperidine, glucamine, glucosamine, hydrabamine, isopropylamine, methylglucamine, morpholine, piperazine, piperidine, procaine, purines, theobromine, triethylamine, trimethylamine, tripropylamine, tromethamine, diethanolamine, meglumine, ethylenediamine, N,N'-diphenylethylenediamine, N,N'-dibenzylethylenediamine, N-benzyl phenylethylamine, choline, choline hydroxide, dicyclohexylamine, metformin, benzylamine, phenylethylamine, dialkylamine, trialkylamine, thiamine, aminopyrimidine, aminopyridine, purine, spermidine, and the like; chiral bases like alkylphenylamine, glycinol, phenyl glycinol and the like, salts of natural amino acids such as glycine, alanine, valine, leucine, isoleucine, norleucine, tyrosine, cystine, cysteine, methionine, proline, hydroxy proline, histidine, ornithine, lysine, arginine, serine, threonine, phenylalanine; unnatural amino acids such as D-isomers or substituted amino acids; guanidine, substituted guanidine wherein the substituents are selected from nitro, amino, alkyl, alkenyl, alkynyl, ammonium or substituted ammonium salts and aluminum salts. Salts may include acid addition salts where appropriate which are, sulphates, nitrates, phosphates, perchlorates, borates, halides, acetates, tartrates, maleates, citrates, succinates, palmoates, methanesulphonates, benzoates, salicylates, hydroxynaphthoates, benzenesulfonates, ascorbates, glycerophosphates, ketoglutarates and the like. Pharmaceutically acceptable solvates may be hydrates or comprising other solvents of crystallization such as alcohols.

Representative compounds prepared according to the process of the present invention may be selected from:
4-(l,l-Dioxo-2,3-dihydrobenzo[b]thiophen-5-yl)-3-(3,4-difluorophenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfanylphenyl)-3-(3,4-difluorophenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-(3,4-difluorophenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfanylphenyl)-3-phenyl-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-phenyl-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfanylphenyl)-3-(4-fIuorophenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfanylphenyl)-3-(4-methylphenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-(4-fluorophenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-(4-methylphenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfanylphenyl)-3-(4-isobutylphenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfanylphenyl)-3-(4-methoxyphenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-(3-methyl-4-methylsulfanylphenyl)-2,5- .
dihydro-2-furanone;
3'Phenyl-4-(3-methoxy-4-methylsulfanylphenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-(4-isobutylphenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfanylphenyl)-3-(4-trifluoromethylphenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-(4-trifluorophenyl)-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfanylphenyl)-3-phenyl-2,5-dihydro-2-furanone;
4'(2-Fluoro-4-methylsulfonylphenyl)-3-phenyl-2,5-dihydro-2-furanone;
4-(4-Methylsulfanyl-3-chlorophenyl)-3-phenyl-2,5-dihydro-2-furanone;
3-(4-Methylsulfanylphenyl)-4-(3-chloro-4-methylsulfanylphenyl)-2,5-dihydro-2-furanone;
4-(4-Methylsulfanyl-3-chlorophenyl)-3-(3,4-difluorophenyl)-2,5-dihydro-2-furanone;
4-(4-Methylsulfanyl-3-fluorophenyl)-3-phenyl-2,5-dihydro-2-furanone;
4-(4-MethyIsulfanyl-3-fluorophenyl)-3-{4-methylsiuIfanylphenyl)-2,5-dihydro-2-furanone;
4-(4-Methylsulfonyl-3-chlorophenyl)-3-phenyl-2,5-dihydro-2-fliranone;
4-(4-Methylsulfanyl-3-chlorophenyl)-3-(4-methylphenyl)-2,5-dihydro-2-fliranone;
4-(4-Methylsulfanyl-3-fluorophenyl)-3-(4-methylphenyl)-2,5-dihydro-2-furanone;
4-(4-MethylsuIfonyl-3-fluorophenyl)-3-phenyl-2,5-dihydro-2-furanone;

4-(4-Methylsulfonyl-3-chlorophenyl)-3-(4-rnethylphenyl)-2,5-dihydro-2-furanone;
4-(4-Methylsulfonyl-3-fluorophenyl)-3-(4-methylphenyl)-2,5-dihydro-2-furanone; '
4-(2-Fluoro-4-methylsulfanylphenyl)-3-(4-trifluoromethylphenyl)-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(4-trifluoromethylphenyl)-2,5-dihydro-2-furanon
4-(3-Methyl-4-methylsulfonylphenyl)-3-(4-methylsulfanylphenyl)-2,5-dihydro-2-furano
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(4-methylphenyl)-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfanylphenyl)-3-(4-isobutylphenyl)-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(4-isobutylphenyl)-2,5-dihydro-2-furanone;
4-(3-Methyl-4-methylsuIfonylphenyl)-3-(4-methoxyphenyl)-2,5-dihydro-2-furanone;
4-(4-Methylsulfanyl-3-fluorophenyl)-3-(4-methoxyphenyl)-2,5-dihydro-2-furanone;
4-(4-Methylsulfonyl-3-fluorophenyl)-3-(4-methoxyphenyl)-2,5-dihydro-2-furanone;
4-(4-Methylsulfonyl-2-chlorophenyl)-3-(4-methoxyphenyl)-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methylsulfanylphenyl)-2,5-dihydro-
2-furanone;
4-(2-Fluoro-4-methylsulfanylphenyl)-3-(4-fluorophenyl)-2,5-dihydro-2-furanone;
4-(4-Methylsulfonyl-3-chlorophenyl)-3-(3,4-difluorophenyl)-2,5-dihydro-2-furanone;
4-(4-Methylsulfanyl-2-chlorophenyl)-3-(4-methoxyphenyl)-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(4-fluorophenyl)-2,5-dihydro-2-furanone;
4-(2,3-Dimethyl-4-methylsulfonylphenyl)-3-phenyl-2,5-dihydro-2-furanone;
4-(3-Fluoro-4-methylsuIfanylphenyl)-3-(3-methyl-4-sulfanylphenyl)-2,5-dihydro-2-
furanone;
4-(3-Fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methylsulfonylphenyl)-2,5-
dihydro-2-furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-(3-fIuoro-4-methylphenyl)-2,5-dihydro-2-
furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-(4-ethylphenyl)-2,5-dihydro-2-furanone; 4-(3-Methyl-4-methylsulfonylphenyl)-3-{3,4-dimethylphenyl)-2,5-dihydro-2-furanone; 4-(3-Methyl-4-methylsulfonylphenyl)-3-(3-bromo-4-methoxyphenyl)-2,5-dihydro-2-
furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(3-fluorophenyl)-2,5-dihydro-2-furanone;
4-(3-Fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methylsulfanylphenyl)-2,5-dihydro-

2-furanone;
4-(2-Fluoro-4-methyIsulfonylphenyl)-3-(l-naphthyl)-2,5-dihydro-2-furanone;
3-(3-Methyl-4-methoxyphenyl)-4-(3-methyl-4-methylsulfonylphenyl)-2,5-dihydro-2-
furanone;
4-(3-Fluoro-4-methylsulfonylphenyl)-3-(4-fluorophenyl)-2,5-dihydro-2-furanone;
4-(3-Fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methoxyphenyl)-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methoxyphenyl)-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methyIsulfonylphenyl)-3-(3-fluorophenyl)-5,5-dimethyl-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(4-fluorophenyl)-5,5-dimethyl-2,5-dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methoxyphenyl)-5,5-dimethyl-2,5-
dihydro-2-furanone;
4-(3-Methyl-4-methylsulfonylphenyl)-3-(3-fluorophenyl)-5,5-dimethyl-2,5-dihydro-2-
furanone;
4-(3-Bromomethyl-4-inethylsulfonylphenyl)-3-(4-fIuorophenyl)-5,5-dimethyl-2,5-
dihydro-2-furanone;
2-{5-[4-(4-Fluorophenyl)-2,2-dimethyl-5-oxo-2,5-dihydro-3-furanyl]-2-methylsulfonyl
benzyl}-2,3-dihydrobenzo[(i]isothiazol-3-oxo-1,1-dioxide;
4-(2-Fluoro-4-methylsulfonylphenyl)- 5,5-dimethyl-3-(3-methyl-4-methylsulfonyl
phenyl)-2,5-dihydro-2-furanone;
5-Ethyl-4-(3-fluoro-4-niethylsulfonylphenyl)- 3-(3-fluorophenyl)-2,5-dihydro-2-
furanone;
3-(4-Fluorophenyl)-5,5-dimethyl-4-(4-methylsulfonyl-3-morpholinomethylphenyl^
dihydro-2-furanone;
5-Ethyl-4-(3-fluoro-4-methylsulfonylphenyl)-3-(4-fluorophenyl)-2,5-dihydro-2-furanone;
3-(3,4-Difluorophenyl)-4-(2-fluoro-4-methylsulfonylphenyl)-2,5-dihydro-2-furanone;
3-(3,5-Difluorophenyl)-4-(2-fluoro-4-methylsulfonylphenyl)-2,5-dihydro-2-furanone;
5-Ethyl-4-(3-fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methylsulfanylphen

dihydro-2-fLiranone;
3-Isopropoxy-5,5-dimethyl-4-(3-methyl-4-methylsulfonylphenyl)-2,5-dihydro-2-
furanone;
4-(3-Hydroxymethyl-4-methylsulfonylphenyl)-3-isopropoxy-5,5-dirnethyl-2,5-dihydro-
2-furanone;
5-Ethyl-4-(3-fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methylsufanylphenyl)-5-
hydroxy-2,5-dihydro-2-furanone;
5-Ethyl-4-(3-fluoro-4-methylsulfonylphenyl)- 3-(4-methoxy-3-methylphenyl)-2,5-
dihydro-2-furanone;
5-Ethyl-4-(3-fluoro-4-methylsulfonylphenyl)- 3-(3,4-difluorophenyl)-2,5-dihydro-2-
furanone;
3-(3,4-Difluorophenyl)-5-ethyl-4-(2-fluoro-4-methylsulfonylphenyl)-2,5-dihydro-2-
furanone;
3-(3,4-Difluorophenyl)-5-ethyl-4-(2-fluoro-4-methylsulfonylphenyl)-5-hydroxy-2,5-
dihydro-2-furanone;
4-(3-Fluoromethyl-4-rnethylsulfonylphenyl)-3-isopropoxy-5,5-dimethyl-2,5-dihydro-2-
furanone;
3-Isopropoxy-5,5-dimethyl-4-(3-fluoro-4-methylsulfonylphenyl)-2,5-dihydro-2-
furanone;
3-Isopropoxy-5,5-dimethyl-4-(3-methylsulfanyl-4-methylsulfonylphenyl)-2,5-dihydro-
2-furanone;
3-Isopropoxy-4-(3-methoxymethyl-4-methylsulfonylphenyl)-5,5-dimethyl-2,5-dihydro-
2-furanone;
4-(3-Formyl-4-methylsulfonylphenyl)-3-isopropoxy-5,5-dimethyl-2,5-dihydro-2-
furanone;
4-(3-Fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methylsulfonylphenyl)-2,5-dihydro-2-furanone; 5-Ethyl-4-(2-fluoro-4-methylsulfonylphenyl)-3-(4-fluorophenyl)-5-hydroxy-2,5-
dihydro-2-furanone;
5-Ethylidene-4-(2-fluoro-4-methylsulfonylphenyl)-3-(3-fluorophenyl)-2,5-dihydro-2-furanone;

5-Ethylidene-4-(2-fluoro-4-methylsulfonylphenyl)-3-phenyl-2,5-dihydro-2-furanone;
5-Ethylidene-4-(2-fluoro-4-methylsulfonylphenyl)-3-(3-methyl-4-methoxyphenyl)-2,5-
dihydro-2-furanone;
4-(3-Fluoro-4-methylsulfonylphenyl)-3-(4-fluorophenyl)-5-methyl-2,5-dihydro-2-
furanone;
4-(3-Fluoro-4-methylsulfonylphenyl)-3-(3-fluorophenyl)-5-methyl-2,5-dihydro-2-
furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(4-fluorophenyl)-5-methyl-2,5-dihydro-2-
furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(3-fluorophenyl)-5-methyl-2,5-dihydro-2-
furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(3,4-difluorophenyl)-5-methyl-2,5-dihydro-2-
furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(3-fluorophenyl)-5-methoxy-5-methyl-2,5-
dihydro-2-furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(4-methylphenyl)-5-rnethyl-2,5-dihydro-2-
furanone;
4-(2-Fluoro-4-methylsulfonylphenyl)-3-(4-fluorophenyl)-5-methoxy-5-methyl-2,5-
dihydro-2-furanone;
l-(4-Fluorophenyl)-4-(3-methyl-4-methylsulfonylphenyl)-3-phenyl-2, 5-dihydro-
lH-2-azolone and
3-(2-Fluoro-4-methylsulfonylphenyl)-l-(4-fluorophenyl)-4-phenyl-2,5-dihydro-lH-2,5-
azoledione.
Accordingly, the compounds of general formula (I) where R1 R2 R3 R4, R5 R6, X and m are as defined earlier can be prepared by any of the following routes shown in Scheme I below:


The reaction of a compound of formula (I-l) with a compound of (1-2) or the reaction of formula (1-3) with a compound of formula (1-4) or the reaction of a compound of formula (1-5) with a compound of formula (1-6) or the reaction of formula (1-7) with a compound of formula (1-8) where L1 represents B(0R)2, wherein R represents hydrogen or (C]-C6)alkyl group, L2 represents halogen atom such as chlorine, bromine or iodine, or other leaving groups such as ZnCl2 or triflate and all other symbols are as defined above to produce a compound of formula (I), where all symbols are as defined above may be carried out in the presence of solvents such as toluene, dimethylformamide (DMF), dioxane, tetrahydrofuran(THF), isopropanol, ethanol, dimethylsulfoxide (DMSO), dichloromethane (DCM), water and the like or mixtures thereof The reaction may be carried out in an inert atmosphere which may be maintained by using inert gases such as He, N2, Ar and the like. The reaction may be carried out in the presence of a catalyst such as bis(triphenyl phosphine)palladium(II)chloride, l,4-bis(diphenyl phosphine butane)palladium (II)chloride, bis(dibenzylideneacetone)palladium(o), palladium acetate, palladium acetate-tri(o-tolyl)phosphine, bis(acetonitrile)palladium(II)chloride, palladium on carbon + triphenyl phosphine, tetrakis(triphenylphosphine)palladium(o) and the like. The

amount of catalyst used may range from 0.1 mol% to 50 mol%, preferably from 1 to 10 mol%. The reaction may be effected in the presence of a base such as alkali metal carbonates like sodium carbonate or potassium carbonate; alkali metal bicarbonates like sodium bicarbonate or potassium bicarbonate; organic bases like triethylamine, pyridine, dimethylaminopyridine (DMAP) or di-isopropylethylamine and the like. The amount of base may range from 1 to 20 equivalents, preferably the amount of base ranges from 1 to 5 equivalents. Phase transfer catalysts such as tetraalkylammonium halide, benzyl triethylammonium halide, benzyl tributylammonium halide, tetraalkylammonium bisulfate, benzyl triethylammonium bisulfate or benzyl tributylammonium bisulfate may be employed. The amount of phase transfer catalyst used may range from 0.01 equivalents to 1 equivalent, preferably from 0.05 to 0.5 equivalents. The reaction temperature may range from 0 °C to reflux temperature of the solvent, preferably from 30 °C to reflux temperature of the solvent. The duration of the reaction may range from 0.5 to 76 h, preferably from 6 to 24 h.
In yet another feature of the present invention, the compounds of general formula (I) where R1, R2, R3 R4 R5 R6 X and m are as defined earlier may be prepared by any of the following routes shown in Scheme-II below:

The reaction of compound of formula (II-1) where all symbols are as defined above with carbon monoxide and water to produce compound of the formula (I) where X represents

oxygen and all other symbols are as defined earlier may be carried out in the presence of suitable palladium catalyst such as PdC2l, Pd(0Ac)2, (PPh3)PdCl2 and the like. The amount of catalyst may range from 0.01 mol % to 5 mol % preferably 2.0 mol %, The reaction may be carried out in the presence of aqueous mineral acids such as HCl or HBr; protic solvents such as EtOH, i-PrOH or BuOH. The reaction temperature may be in the range of-78 °C to 300 °C, preferably at a temperature in the range of 20°C to reflux temperature of the solvent used and the reaction may be carried out at 50 to 150 atmospheric pressure of carbon monoxide. The duration of the reaction may range from 2 to 80 h.
Alternatively, the compound of formula (I), where X represents oxygen and all symbols are as defined earlier, may be prepared by reacting a compound of formula (II-1), where all symbols are as defined earlier, with transition metal carbonyl complexes like Rh4(CO)i2 or Rh6(CO)16. The reaction may be carried out in the presence of solvents such as THF, acetone, acetonitrile, benzene, toluene, EtOH, MeOH and the like or mixtures thereof The reaction may be carried out in the presence of a base such as trialkyl amine like triethyl amine, di-isopropyl ethylamine and the like. The temperature may range from 30 to 300°C, preferably at a temperature in the range of 50 to 150°C at 20 to 300 atmosphere of pressure. The reaction may be carried out in an inert atmosphere, which may be maintained by using inert gases such as N2, Ar or He. The duration of the reaction may range from 2 to 80 h.
The reacfion of compound of formula (II-2), where L3 represents halogen atom such as chlorine, bromine or iodine, and all other symbols are as defined above, with the compound of formula (II-3) where X represents oxygen or NR8 and R4 is as defined earlier or the reaction of
o
a compound of formula (II-4) where X represents oxygen or NR and all other symbols are as defined earlier with a compound of formula (11-5) where L4 represents hydroxy, halogen atom such as chlorine, bromine or iodine to produce a compound of formula (I) where all symbols are as defined earlier may be carried out in the presence of base such as triethylamine (TEA), 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, Na2C03, K2CO3, NaOH, KOH, NaOMe, NaOEt, NaOiPr, t-BuOK, NaH, KH and-the like. The amount of base may range from 1 to 5 equivalents, preferably the amount of base ranges from 2 to 3 equivalents. The reaction may be carried using solvents such

as THE, N-methyl pyrrolidine, acetonitrile, propionitrile, acetone, 2-butanone, DMSO, DMF, dimethylamine (DMA), DCM, CHCI3 and the like or mixtures thereof The reaction may be carried in an inert atmosphere which may be carried out using inert gases such as He, N2, Ar and the like. The reaction temperature may be in the range of 0 °C to 150 °C, preferably at a temperature in the range of 20°C to reflux temperature of the solvent used. The duration of the reaction may range from 2 to 50 h, preferably from 2 to 20 h. In case of incomplete dehydration, the hydrated compound is further dehydrated.
Alternatively, the reaction of compound of formula (II-2) where L3 represents a halogen atom such as chlorine, bromine or iodine, and all other symbols are as defined above with a compound of formula (II-3) where X represents oxygen or NR and R is as defined earlier or the reaction of a compound of formula (11-4) where X represents oxygen or NR8 and all other symbols are as defined earlier with a compound of formula (II-5) where L4 represents hydroxy, halogen atom such as chlorine, bromine or iodine to produce a compound of formula (I) where all symbols are as defined earlier may be carried out in the presence of 2 equivalents of N, Nl-dicyclohexylcarbodiimide (DCC) + 0.5 equivalents of DMAP or carboxymethylcellulose (CMC) + DMAP. The reaction may be carried out in the presence of solvents such as DCM, CHCI3, benzene, toluene, xylene, and the like or mixtures thereof The reaction temperature may be in the room temperature to reflux temperature of the solvents used. The duration of the reaction may range from 2 to 12 h.
According to another feature of the present invention, the compound of formula (I) where R1 represents amino group, m represents 2 and all other symbols are as defined above may be prepared by transforming a compound of formula (I) where R1 represents lower alkyl group, m represents 2 and all other symbols are as defined earlier in the presence of a Grignard reagent like MeMgCl, MeMgBr, EtMgCl or a base such as nBuLi, LiNH2 or LDA. The reaction may be carried out in the presence of trialkyl borane such as triethyl borane or tributyl borane in the presence of a solvent such as dioxane, diethylether, di-isobutylether, diphenylether, THF and the like or mixtures thereof The reaction may be carried out in inert atmosphere which may be maintained by using Ar, N2 or He. The reaction may be carried out in the temperature range of-78 °C to the reflux temperature of solvent used, preferably at 0 °C to reflux temperature of the solvent used. The reaction may be more effective under anhydrous condition. The duration of the reaction may be in the range of 12 to 72 hours, preferably in the

range of 15 to 24 hours. The oxidative amination reaction may be carried out in presence of hydroxylamine-0 sulfonic acid and NaOAc. The temperature range of 0 °C to reflux temperature of the solvent, preferably 0 to 50 °C may be used. The duration of the reaction may be 2 to 20 h, preferably 2 to 10 h.
According to another feature of the present invention the compound of formula (I) where all symbols are as defined earlier and m represents 0 may be prepared by reducing a compound of formula (I) where all symbols are as defined earlier and m represents 1 or 2. The reduction may be carried out using reagents such as LAH, HI, Bu3SnH, TiCl3 MeSiCl3, Nal, PCI3, H2-Pd-C, acetyl chloride, PPha, t-BuBr and tris(dimethylamino)phosphine-l2. The reduction may also be carried out using diisobutyl aluminium hydride[(iBu)2AlH], LAH according to the procedure described in J. Org. Chem. 48, (1983) 1617.
In yet another embodiment of the present invention, the compound of formula (I) where all symbols are as defined earlier and m represents 1 (sulfoxide) or m represents 2 (sulfone) may be prepared by oxidising a compound of formula (I) where all symbols are as defined earlier and m represents 0 with a suitable oxidising agent. The oxidation of a compound of formula (I) where m is 0 may be carried out in the presence of an oxidising agent such as 30 % H2O2, m-CPBA, oxone (potassium peroxy monosulfate), NaI04, KMn04, sodiumperborate, magnesium monoperoxy phthalate hexahydrate and the like. The quantity of the reagent varies from 2 mol to 20 mol preferably 4 to 10 mol. The reaction may be effective in presence of a solvent such as CHCI3, t-butanol, CH2CI2, acetone, CH3COOH and the like or mixtures thereof Water may be used as cosolvent. 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 temperature in the range of 0 to 150°C, preferably in the range of 30 to 120°C. The duration of the reaction may range from 0.5 to 24 h, preferably 0.5 to 12 h.
In yet another embodiment of the present invention the compound of general formula (II-2) where L3 represents halogen atom, R1 and R2 together with the atoms which they are attched forms a ring and the ring is selected fi"om dihydrothiophene, R5, R6 represent hydrogen and R3 is as defined earlier, may be prepared by a process shown in the Scheme-Ill below:


The oxidation of compound of formula (II-2a) where R3 is as defined above to produce a compound of formula (II-2b) where R3 is as defined above may be carried out using oxidizing agents such as hydrogenperoxide, potassium permanganate, meta chloro per benzoic acid (m-CPBA), NaI04, t-BuOCl, sodium perborate, potassium hydrogen persulfate and the like. The quantity of oxidizing agent used may vary from 1 to 20 equivalents, preferably 2-10 equivalents. The reaction may be carried out in the presence of solvents such as glacial acetic acid, propionic acid, water and the like or mixtures thereof The reaction may be carried out in an inert atmosphere which is maintained by using inert gases such as He, N2 or Ar. The reaction temperature may range from 20°C to reflux temperature of solvent used, preferably from 50°C to the reflux temperature of the solvent used. The duration may vary from 15 min to 15 h, preferably 15 min to 3 h.
The reduction of compound of formula (II-2b) defined above to a compound of formula (II-2c) where R3 is as defined above, may be carried out using 5-10% Pd-C catalyst, Raney-Nickel, Pt/C, Nickel boride and the like. The quantity of catalyst may vary from 0.01 to 1.0%
1

w/w, preferably from 0.01 to 0.50% w/w. The reaction may be carried out in the presence of solvents such as acetic acid, methanol, ethanol and the like or mixtures thereof The reaction may be effected in H2 atmosphere, the pressure varying from 1to 20 atm, preferably 1 to 10 atm. The reaction may be carried out in an inert atmosphere which is maintained by using inert gases such as He, N2 or Ar. The reaction temperature may range from 15 to 100°C, preferably from 15 to 50°C, The duration of the reaction may vary from 0.5 to 20 h, preferably from 0.5 to 5 h.
The reduction of compound of formula (II-2c) defined above to a compound of formula (II-2d) where R3 is as defined above, may be carried out using reducing agents such as LAH, HI, Bu3SnH, TiCl2, MeSiCl3, Nal, PCI3, H2-Pd/C, PPh3, t-BuBr, tris(dimethylamino)phosphine-I2 and the like. The quantity of reducing agent may vary from 0.5 to 10 equivalents, preferably from 1 to 5 equivalents. The reaction may be carried out in the presence of solvents such as (C1-C8 linear or branched) alkylether, THF, dioxane and the hke. The reaction may be carried out in an inert-atmosphere, which is maintained by using inert gases such as He, N2 or Ar. The reaction temperature may range from 0°C to the reflux temperature of the solvent used and the duration of reaction ranges from 1 to 80 h, preferably from 1 to 24 h. The reaction may be carried out under anhydrous conditions.
The reaction of compound of formula (II-2d) defined above with acetyl chloride to produce a compound of formula (II-2e) where R3 is as defined above, may be carried out in the presence of solvents such as dichloromethane, ethylene dichloride, chloroform, nitrobenzene and the like or mixtures thereof The quantity of acetyl chloride may vary from 1 to 10 equivalents, preferably 1 to 5 equivalents. The reaction may be effected using catalysts such as Al.Hal3(where Hal is F, CI or Br). The quantity of the catalyst may range from 1 to 10 equivalents, preferably 1 to 5 equivalents. The reaction may be carried out in an inert atmosphere which is maintained by using inert gases such as He, N2 or Ar. The temperature of the reaction may range from -20°C to the reflux temperature of the solvent used, preferably -20°C to 50°C. The duration of the reaction may vary from 1 to 80 h, preferably from 4 to 24 h.
The oxidafion of compound of formula (II-2e) defined above to produce a compound of formula (11-21) where R3 is as defined above may be carried using oxidizing agents such as hydrogenperoxide, potassium permanganate, m-CPBA, NaI04, t-BuOCl, sodium perborate, potassium hydrogen persulfate and the like. The quantity of oxidizing agent used may vary

from 1 to 20 equivalents, preferably 2-10 equivalents. The reaction may be carried out in the presence of solvents such as glacial acetic acid, propionic acid, water and the like or mixtures thereof. The reaction may be carried out in an inert atmosphere, which is maintained by using inert gases such as He, N2 or Ar. The reaction temperature may range from 20°C to reflux temperature of solvent used, preferably from 50°C to the reflux temperature of the solvent used. The duration may vary from 15 min to 15 h, preferably 15 min to 3 h.
The reaction of compound of formula (n-2f) defined above to produce a compound of formula (II-2) where L^ represents halogen atom and all other symbols are as defined above may be carried out using halogenating agent such as NIS, NBS, bromine, Cu-Hal where Hal represents halogen atom in the quantity varying from 0.5 to 5 equivalents, preferably 0.5 to 1.5 equivalents, in the presence of solvents such as acetic acid, methanol, toluene, dichloromethane. The reaction may be effected in the presence of catalyst such as HBr, HCl in the quantity varying form 0.01 to 1.0% w/w, preferably 0.01 to 0.5% w/w. The temperature of the reaction may range from 15°C to reflux temperature of the solvent used, preferably from 15 to 75°C. The duration of the reaction may vary from 1 to 20 h, preferably from 1 to 10 h.
It is appreciated 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 those used conventionally in the art. The methods of formation and removal of such protecting groups are those conventional methods appropriate to the molecule being protected.
The compound of formula (I) when produced through an intermediate compound, conventional functional group transformations such as hydrolysis, reduction or oxidation may be carried out.
The following examples illustrate some of the functional group transformations :
The compounds of formula (I) having CONH2 groups may be transformed to CN by following a procedure disclosed in International publication WO No. 99/15505
Similarly, the compound of formula (I) having CO2Et group may be transformed to CH2OH by following a procedure disclosed in International publication No. WO 95/15316.
The pharmaceutically acceptable salts are prepared by reacting the compounds of formula (I) wherever applicable with 1 to 4 equivalents of a base such as sodium hydroxide, sodium methoxide, sodium hydride, potassium t-butoxide, calcium hydroxide, magnesium

hydroxide and the like, in solvents like ether, THF, methanol, t-butanol, dioxane, isopropanol, ethanol etc. Mixture of solvents may be used. Organic bases like lysine, arginine, diethanolamine, choline, tromethamine, guanidine and their derivatives etc. may also be used. Alternatively, acid addition salts wherever applicable are prepared by treatment with acids such as hydrochloric acid, hydrobromic acid, nitric acid, sulfuric acid, phosphoric acid, p-toluenesulphonic acid, methanesulfonic acid, acetic acid, citric acid, maleic acid salicylic acid, hydroxynaphthoic acid, ascorbic acid, palmitic acid, succinic acid, benzoic acid, benzenesulfonic acid, tartaric acid and the like in solvents like ethyl acetate, ether, alcohols, acetone, THF, dioxane etc. Mixture of solvents may also be used. The salts of amino acid groups and other groups may be prepared by reacting the compounds of formula (I) with the respective groups in solvents like alcohols, ketones, ether etc. Mixture of solvents may be used.
The stereoisomers of the compounds of formula (I) 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 sahs formed with chiral acids such as mandelic acid, camphorsulfonic acid, tartaric acid, lactic acid and the like or chiral bases such as brucine, cinchona alkaloids and their derivatives and the like.
The regioiosmers of compound of formula (I) may be prepared by modifying the reaction conditions, use of reagents like acid to base or base to acid or by reaction with free base hydrazine instead of its salt with diketone. The molar proportion also can change the regiosiomer formation.
Various polymorphs of compound of general formula (I) forming part 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. Polymorphs may also be obtained by heating or melting the compound followed by gradual or slow cooling. The presence of polymorphs may be determined by solid probe NMR spectroscopy, IR spectroscopy, differential scanning calorimetry, powder X-ray data or such other techniques.

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 compounds of the general formula (I) are useful as partial or complete substitute for NSAIDS in compositions or preparations wherein they are presently coadministered with other agents or ingredients..
The nvention 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.
Preparation 1; 3-Fluoroanisole
To an ice cold (- 0°C) solution of 3-fluoroaniline (50 g, 450.45 mmol) in 6N hydrochloric acid (200 ml) was added 150 ml of ice cold (- 5°C) aqueous solution of NaN02 (37.3 g, 540.58 mmol) very slowly and drop wise. Temperature of the reaction mixture was maintained strictly at 0-5°C by occasional addition of ice and sahs out side the reaction flask. The diazotised solution of 3-fluoroaniline was then added very slowly (not more than 2 ml at a time) to an aqueous solution of ethyl potassium xanthate (101.5 g, 634.37 mmol in 100 ml of H2O) at 40-45°C. The duration of addition was 1.5 h. The reaction mixture was then stirred for 1 h at 40-45°C. The aqueous layer was decanted out from the orange colored oil that was extracted with chloroform (3 x 100 ml). The combined organic layers washed with 5N NaOH solution (2 x 50 ml) followed by water (2 x 100 ml), dried over anhydrous Na2S04 and concentrated under low vacuum. The crude oil thus obtained was used for the next step.
To the.solution of above product in ethanol (250 ml) was added KOH pellets (37.91 g, 675.63 mmol) carefully. The mixture was then heated to 85-90°C under nitrogen atmosphere with vigorous stirring for 27 h. Ethanol was removed under low vacuum and the resulting residue was dissolved in acetone (200 ml). The mixture was cooled to -10°C to which methyl

iodide (127,87g, 900.87 mmol) was added slowly and drop wise. After stirring for 12 h at room
temperature solvent was removed under vacuum and petroleum ether (200 ml) was added to the
residue. Filtration of the mixture through celite followed by the concentration of the filtrate
gave crude product which was purified by distillation at 83-85°C under 40 mm Hg to afford 31
g of title compound (49 % yield) as oil.
1H NMR (CDCI3, 200 MHz): 5 7.29-7.18 (m, 1H), 7.02-6.77 (m, 3H), 2.48 (s, 3H).
Mass (CI, i-Butane) m/z 142 (M+, 20), 96 (100).
Preparation 2: 2-Fluorothioanisole

2-Fluorothioanisole was prepared in 71% yield from 2-fluoroaniline (30 g, 270.27 mmol) using NaN02 (22.37 g, 324.49 mmol), ethyl potassium xanthate (43.51 g, 271.4 mmol) and methyl iodide (76.72 g, 540.21 mmol) according to the procedure described in preparation 1. 1H NMR (CDCI3, 200 MHz): 5 7.36-7.00 (m, 4H), 2.47 (s, 3H).
Preparation 3: 2,3-Dimethylthioanisole

2,3-Dimethylthioanisole was prepared in 78% yield from 2,3-dimethylaniline (5 g, 41.32 mmol) using NaN02 (5.13 g, 74.37 mmol), ethyl potassium xanthate (7,90 g, 49.28 mmol) and methyl iodide (6.10 g, 42.95 mmol) according to the procedure described in preparation 1. 1H NMR (CDCI3, 200 MHz): 8 7.2-6.9 (m, 3H), 2.46 (s, 3H), 2.32 (s, 3H), 2.31 (s, 3H).

Preparation 4: 2-Chlorothioanisole
2-Chlorothioanisole was prepared in 89% yield from commercially available 2-chlorothiophenol (4.0 g, 27.6 mmol) using methyl iodide (4.66 g, 32.81 mmol) according to the procedure described in preparation 1. 1H NMR (CDCI3, 200 MHz): 5 7.31-6.92 (m, 4H), 2.46 (s, 3H).
Preparation 5: 2-Fluoro-4-miethylsulfanyl acetophenone

To a suspension of AICI3 (45 g, 339 mmol) in dichloromethane (150 ml) was added acetyl chloride (24.2 ml, 339 mmol) drop wise at O°C. The mixture was stirred for 0.5 h at 25°C until a clear solution was obtained. To this was added a solution 3-fluorothioanisole (37 g, 260.5 mmol) in dichloromethane (50 ml) slowly at 0°C. The duration of addition was 30 min. The mixture was then stirred for 3 h at 25°C, poured into ice (500 g), extracted with chloroform (3 X 100 ml). Combined organic layers were washed with water (2 x 100 ml), dried over anhydrous Na2S04 and concentrated under vacuum to give crude product. This was purified by column chromatography over silica gel using 1% EtOAc-Petroleum ether as eluant to give 14 g (29% yield) of the title compound as light brown solid, m.p.: 61-62°C.
1H NMR (CDCI3, 200 MHz): 5 7.85-7.77 (m, IH), 7.06-7.01 (d, J- 8.79 Hz, IH), 6.90-6.86 (d, J- 8.3 Hz, 1H), 2.62-2.60 (d, J= 4.88 Hz, 3H), 2.52 (s, 3H). Mass (CI, i-Butane) m/z 183 (M+ 47), 169 (100), 155 (89).


3-Fluoro-4-methylsulfanyl acetophenone was prepared in 22% yield from 2-fluorothioanisole (9 g, 63.38 mmol) using acetylchloride (5.97 g, 76.05 mmol) and AICI3 (10.11 g, 75.82 mmol) according to the procedure described in preparation 5.
1H NMR (CDCI3, 200 MHz): 5 7.72-7,50 (m, 2H), 7.30-7.15 (t, J= 7.8 Hz, IH), 2.56 (s, 3H), 2.51 (s,3H).
Preparation 7: 2,3-Dimethyl-4-methylsulfanyI acetophenone

2,3-Dimethyl-4-methylsulfanyl acetophenone was prepared in 28% yield from 2,3-dimethylthioanisole (7.5 g, 49.01 mmol) using acetylchloride (4.60 g, 58.59 mmol) and AICI3 (7.80 g, 58.49 mmol) according to the procedure described in preparation 5. 1H NMR (CDCI3, 200 MHz): 5 7.54-7.49 (d, J= 8.71 Hz, IH), 6.75-6.65 (d, J= 8.72 Hz, IH), 2.55 (s, 3H), 2,49 (s, 3H), 2.42 (s, 3H), 2.30 (s, 3H).
Preparation 8: 3-Chloro-4-methyIsulfanyl acetophenone


3-Chloro-4-methylsulfanyl acetophenone was prepared in 69% yield from 2-chlorothioanisole (5,0 g, 31.54 mmol) using acetylchloride (2.7 ml, 37.83 mmol) and AICI3 (4.56 g, 34.19 mmol) according to the procedure described in preparation 5. 1H NMR (CDCI3, 200 MHz): 5 7.90-7.71 (m, 2H), 7.17 (d, J= 8.0 Hz, IH), 2.55 (s, 2H), 2.52 (s, 3H).
Preparation 9: 2-Bromo-l-(2-fluoro-4-methylsulfanylphenyI)-l-ethanone

To a solution of 2-fluoro-4-methylsulfanyl acetophenone (12 g, 65.2 mmol) in acetic acid (100 ml) was added hydrobromic acid (5 ml) at 10-15°C. The mixture was stirred for 10-15 min. To this stirring mixture was added a solution of bromine (3.18 ml, 61.72 mmol) in acetic acid (4 ml) very slowly. Stirring continued for 3 h until the color of bromine disappeared. Water (300 ml) was added to this mixture, the solid separated was filtered and dried under vacuum. The powder thus obtained was treated with petroleum ether (20 ml) to remove color impurities and then filtered to give 13.3 g of title compound in 78% yield as pale brown solid, m.p. 55-59°C.
1H NMR (CDCI3, 200 MHz): 5 7.91-7.83 (m, 1H), 7.09-7.05 (d, J= 8.7 Hz, 1H), 6.98-6.92 (d, J- 12.2 Hz, 1H), 4.48-4.47 (d, J- 1.96 Hz, 2H), 2.52 (s, 3H). Mass (CI, i-Butane) m/z 262 (M+ 8), 169 (100).

Preparation 10: 2-Bromo-l-(3-fluoro-4-methylsulfanylphenyl)-l-ethanone

2-Bromo-l-(3-fluoro-4-methylsulfanylphenyl)-l-ethanone was prepared in 67% yield from 2-fluoro-4-methylsulfanyl acetophenone (2 g, 10.86 mmol) using bromine (0.58 ml, 11.25 mmol) according to the procedure described in preparation 9.
1H NMR (CDCI3, 200 MHz): 8 7.75-7.63 (m, 2H), 7.30-7.15 (t, J= 7.40Hz, IH), 4.38 (s, 2H), 2.53 (s, 3H).
Preparation 11:
2-Bromo-l-(2, 3-dimethyi-4-methylsulfanyIplienyl)-l-ethanone

2-Bromo-l-(2, 3-dimethyl-4-methylsulfanylphenyl)-l-ethanone was prepared in 79% yield from 2,3-dimethyl-4-methylsulfanyl acetophenone (1.8 g, 9.2 mmol) using bromine (0.45 ml, 8.73 mmol) according to the procedure described preparation 9.
1H NMR (CDCI3, 200 MHz): 8 7.78-7.56 (d, J= 8.21 Hz, IH), 6.89-6.76 (d, J= 8.22 Hz, IH), 4.31(s, 2H), 2.51 (s, 3H), 2.43 (s, 3H), 2.33 (s, 3H).
Preparation 12: 2-Bromo-l-(3-chloro-4-methylsulfanyiphenyl)-l-ethanone

2-Bromo-l-(3-chloro-4-methylsulfanylphenyl)-l-ethanone as prepared in 55% yield from 3-chloro-4-methylsulfanyl acetophenone (6.6 g, 33 mmol) using bromine (1.60 ml, 31.01 mmol) according to the procedure described in preparation 9.

- ^H NMR (CDCI3, 200 MHz): 5 8.02-7.81 (m, 2H), 7.19 (d, J- 8,0 Hz, IH), 4.36 (s, 2H), 2.52 (s, 3H).
Preparation 13: Benzothiophene-l,l-dioxide
To a solution of benzothiophene (10 g, 74.6 mmol) in glacial acetic acid (18.65 ml) 30% aqueous H2O2 (37.31 ml, 329.20 mmol) was added and refluxed for 0.5 h. The reaction mixture was cooled slowly to 10-15°C, filtered, washed with chilled water (15 ml) and dried to yield the title compound as white solid (12 g, 97 %). m.p. 129-130°C,
1HNMR(CDCl3, 200 MHz): 5 7.74 (d, J = 7.80 Hz, IH), 7.68-7.54 (m, 2H), 7.38 (d, J- 2.40 Hz, IH), 7.24 (d, J - 7.00 Hz, IH), 6.72 (d, J = 6.80 Hz, IH).
Preparation 14: 2,3-Dihydrobenzothiophene-l,l-dioxide

A solution of benzothiophene-1,1-dioxide (10 g, 60.24 mmol) obtained in preparation 13 dissolved in glacial acetic acid (400 ml) was charged with 5 - 10 % Pd-C (100 mg, 0.01 wt %) and hydrogenated using H2 gas for 5 h. The reaction mixture was filtered using celite bed and the filtrate poured into ice water (500 ml), extracted with ethylacetate, dried (Na2S04) and evaporated to yield gummy mass which was chromatographed over silica gel column using ethylacetate : pet. ether (10 : 90) to yield the title compound (10 g, 99 %). m.p. 91- 92°C. 1HNMR (CDCI3, 200 MHz): 5 7.76-7.73 (d, J = 7.60 Hz, IH), 7.62-7.40 (m, 3H), 3,53-3.50 (t, J = 6.20 Hz, 2H), 3.39-3.36 (t, J = 6.00 Hz, 2H).

Preparation 15: 2,3-Dihydrobenzothiophene
To 2,3-dihydrobenzothiophene-l,l-dioxide (10 g, 59.52 mmol) obtained in preparation 14, lithium aluminum hydride (5.65 g, 148,80 mmol) and THF (100 ml) was added under argon atmosphere and refluxed for 4-5 h. The reaction mixture was cooled to 10°C and adding water dropwise slowly quenched excess lithium aluminum hydride. THF was removed under reduced pressure. Water (100 ml) and ethyl acetate (100 ml) was added and stirred. The water layer was extracted with ethyl acetate. The combined ethyl acetate layers were dried (Na2S04) and evaporated to yield the crude product, which was chromatographed over silica gel column using 2 % ethylacetate and pet. ether as eluent to afford the title compound as viscous liquid. 1HNMR (CDCI3, 200 MHz): 8 7.26-7.01 (m, 4H), 3.3 9-3.26 (m, 4H).
Preparation 16:
5-AcetyI-2, 3-dihydrobenzothiophene

2,3-Dihydrobenzothiophene (8 g, 58.8 mmol) obtained in preparation 15 was slowly added to slurry of anhydrous aluminum chloride (11.77 g, 88.2 mmol) and acetylchloride (6.92 g, 88.2 mmol) in dichloromethane (100 ml) at 5-10°C. The reaction mixture was stirred at 25-30°C for 24 h and then poured into crushed ice. Extracted with dichloromethane (2 x 50 ml), dried (Na2S04) and evaporated to yield the title compound as viscous liquid (10 g, 96 %). 1HNMR (CDCI3, 200 MHz): 5 7.77 (s, 1H), 7.74-7.70 (d, J-9.70 Hz, 1H), 7.28-7.24 (d, J = 7.98 Hz, IH), 3.47-3.34 (m, 4H), 2.55 (s, 3H),

Preparation 17; 5-Acetyl-2,3-dihydrobenzothiophene-l,l-dioxide

To a solution of 5-acetyl-2,3-dihydrobenzothiophene (8 g, 44.9 mmol) obtained in preparation 16 in glacial acetic acid (16 ml), 30 % aqueous H2O2 solution (22.92 ml, 202.2 mmol) was added and refluxed for 1 h. After cooling to 20°C, the separated solid was filtered and washed with water to yield the title compound (9 g, 96 %), m.p. 54-56°C. 1HNMR (CDCI3, 200 MHz): 8.02 (m, 2H), 7.82 (d, J = 8.20 Hz, IH), 3.57-3.51 (dt, J-5.60 Hz, 4H), 2.64 (s, 3H).
Preparation 18: 5-Bromoacetyl-2,3-dihydrobenzothiophene-l,l-dioxide

To a solution of 5-acetyl-2,3-dihydrobenzothiophene-l,l-dioxide (8 g, 38.1 mmol) (obtained in preparation 17) dissolved in acetic acid (45 ml) under argon atmosphere, aqueous HBr (0.5 ml, 47 %), bromine (5.84 g, 36,54 mmol) was added slowly at 15-20°'C and the reaction mixture was stirred for about 0.5 h. Additional quantity of bromine (4.84 g) was slowly added and the stirring continued for further 10 h at 25-30°C. Argon atmosphere was removed and the reaction mixture was kept open in the wave of blowing air in the fuming cup board to eliminate free bromine. The solid separated was filtered and washed with acetic acid (2 X 10 ml) followed by pet. ether to yield the title compound (10 g, 91 %). mp. 68-70°C. 1HNMR (CDCI3, 200 MHz): 8.06 (d, J = 8.20 Hz, 1H), 8.00 (s, 1H), 7.86 (d, J-8.40 Hz, 1H), 4.44 (s, 2H), 3,62-3.40 (dt, J = 5.40 Hz, 4H).

Preparation 19: 2-(4-FluoroaniIino)-l-(3-methyl-4-methylsulfonylphenyl)-l-ethanone

To a mixture of p-fluoroaniline (1.14 g, 10.3 mmol) and NaHCOs (0.865 g, 10.3 mmol) in ethanol (25 ml) was added 2-bromo-l-(3-methyl-4-methylsulfonyl) acetophenone (3 g, 10.3 mmol) under nitrogen atmosphere at 25°C. The mixture was stirred vigorously for 3.5 h at the same temperature and then diluted with water (100 ml). The solid separated was filtered, washed with water (2 x 25 ml) followed by petroleum ether (2 x 10 ml) and dried under vacuum to give 2.9 g of the title compound in 88% yield.
1H NMR (CDCI3, 200 MHz): 5 8.19-8.15 (d, J= 8.7 Hz, 1H), 7.96-7.93 (m, 2H), 6.97-6.88 (m, 2H), 6.68-6.62 (m, 2H), 4.59 (s, 2H), 3.10 (s, 3H), 2.79 (s, 3H).

2-(4-Fluoroanilino)-l-(3-methyl-4-methylsulfonylphenyl)-l-ethanone was prepared in 95% yield using p-fluoroaniline (0.22 g, 1.96 mmol) and 2-bromo-l-(2-fluoro-4-methylsulfanylphenyl)-l-ethanone (0.6g, 1.96 mmol) according to the procedure described in preparation 19.
1H NMR (CDCI3, 200 MHz): 5 8.22-8,14 (m, 1H), 7.85-7.78 (m, 2H), 6.95- 6.87 (m, 2H), 6.65-6.59 (m, 2H), 4.55 (s, 2H), 3.09 (s, 3H).

Preparation 21:
N1-(4-Fluorophenyl)-N'-[2-(3-methyl-4-methylsulfonylphenyI)-2-oxoethyl]-2-
1phenylacetamide
To a solution of 2-(4-fluoroanilino)-l-(3-methyl-4-methylsulfonylphenyl)-l-ethanone (1.5 g, 4.67 mmol) (obtained in preparation 19) in anhydrous THF (15 ml) was added phenacylchloride (0.722 g, 0.62 mmol) very slowly under nitrogen atmosphere at 25°C. The mixture was stirred for 2 h and diluted with water (25 ml). The solid separated was filtered, washed with water (2x15 ml) followed by petroleum ether (2x5 ml) and dried under vacuum to give 1.6 g of the title compound in 78% yield.
1H NMR (CDCI3, 200 MHz): 8 8.14-8.10 (d, J= 8.8 Hz, 1H), 7.89-7.86 (m, 3H), 7.39-7.00 (m, 9H), 5.04 (s, 2H), 6.57 (s, 2H), 3.08 (s, 3H), 2.75 (s, 3H).
Preparation 22:
N^-(4-Fluorophenyl)-N'-[2-(2-fluoro-4-methylsuIfonylphenyI)-2-oxoethyl]-2-
phenylacetamide
N'-(4-Fluorophenyl)-N'-[2-(3-methyl-4-methylsulfonylphenyl)-2-oxoethyl]-2-phenylacetaomide was prepared in 93% yield from 2-(4-fluoroaniIino)-l-(2-fluoro-4-methylsulfonylphenyl)-l-ethanone (0.55 g, 1.84 mmol) and phenacyl chloride (0.285 g, 1.84 mmol) according to the procedure described in preparation 21.
1H NMR (CDCI3, 200 MHz): 5 8.18-8.11 (m,1H), 7.84-7.73 (m, 2H), 7.35-7.04 (m, 9H), 4.95 (s,2H), 3.56 (s,2H), 3.08 (s,3H).


To a solution of 4-fluorophenylacetic acid (7.6 g, 49.3 mmol) in DMF (30 ml) was added aqueous solution of KOH (2.7 g, 48.11 mmol in 5 ml water) and the mixture was stirred at 25 ''C for 30 min. To this mixture was added a solution of 2-Bromo-l-(2-fluoro-4-methylsulfanylphenyl)-l-ethanone (13 g, 49.3 mmol) in DMF (100 ml) and stirring continued for 1 h at 25'C. Water (500 ml) was added to this, the solid separated was filtered and dried under vacuum. The crude solid was treated with isopropanol and filtered to give 15 g of title compound in 90% yield as pale brown solid, m.p. 78-81°C.
1H NMR (CDCI3, 200 MHz): 5 7.91-7.83 (t, J= 7.8Hz, IH), 7.35-7.28 (m, 2H), 7.08-6.90(m, 4H), 5.21-5.20 (d, J= 3.42 Hz, IH), 3.78 (s, 2HX 2.51 (s, 3H). Mass (CI, i-Butane) m/z 336 (M+, 8), 169 (100). Step 2:
Preparation of 3-(4-fluorophenyl)-4-(2-fluoro-4-methylsulfanylphenyl)-2,5-dihydro-2-furanone.


To a solution of 2-(2-fluoro-4-methylsulfanylphenyl)-2-oxyethyl-2-(4-fluorophenyl) acetate (12 g, 35.7 mmol)(obtained in step 1) in acetonitrile (100 ml) was added 1,8-diazabicyclo[5.4.0] undec-7-ene (DBU) (11 ml, 71.5 mmol) drop wise at 25 °C under nitrogen atmosphere. The mixture was stirred for 30 min. at same temperature. Water (200 ml) was added to this followed by the addition of 2N HCl (200 ml). The mixture was then extracted with EtOAc (2 x 250 ml), organic layers were collected, combined, dried over anhydrous Na2S04 and concentrated. The crude product thus obtained was purified by column chromatography over silica gel using 10% EtOAc-petroleum ether to give 5 g of the title compound in 44% yield as white solid, m.p. 118-122°C.
1H NMR (CDCI3, 200 MHz): 5 7.45-7.38 (m, 2H), 7.25-6.87 (m, 5H), 5.17 (s, 2H), 2.48 (s, 3H).
Mass (CI, i-Butane) m/z 318 (M^ 100), 261 (85). Step 3:
Preparation of 3-(4-fluorophenyl)-4-(2-fluoro-4-methylsulfonylphenyl)-2,5-dihydro-2-furanone.
To a solution of 3-(4-fluorophenyl)-4-(2-fluoro-4-methylsulfanylphenyl)-2,5-dihydro-2-furanone (6 g, 18.8 mmol) (obtained in step 2) in acetone (150 ml) was added a solution of oxone (34.8 g, 56.6 mmol) in water (75 ml). The reaction mixture was stirred vigorously for 2 h at 25°C. After completion of the reaction solvent was removed under low vacuum and water (200 ml) was added to it. The mixture was then extracted with EtO Ac (2 x 100 ml), organic layers collected, combined, dried over anhydrous Na2S04 and concentrated under vacuum. The crude product was then treated with MeOH (2 x 20 ml) and filtered to give 5.6 g of title compound in 85% yield as off white powder, m.p. 160-162°C.
1H NMR (CDCI3, 200 MHz): 5 7.77-7.66 (m, 2H), 7.45-7.35 (m,3H), 7.25-7.01 (m, 2H), 5.19 (s,2H),3.09(s,3H). Mass (CI, i-Butane) m1z 350 (M+ 50), 322 (10), 293 (100).

To a solution of N'-(4-fluorophenyl)-N1-[2-(3-methyl-4-methylsulfonylphenyl)-2-oxoethyl]-2-phenylacetamide (1 g, 2.27 mmol) in acetonitrile (15 ml) was added DBU (0.346 g, 2.27 mmol) under nitrogen atmosphere at 0-5°C. The mixture was stirred for 4 h, poured into water (50 ml) and extracted with EtOAc (3 x 15 ml). The organic layers were isolated, combined, dried over anhydrous Na2S04 and concentrated under vacuum. The residue isolated was purified by column chromatography using EtOAc-petroleum ether (1:3) as eluent to give 0.2 g of the title compound in 21% yield, m.p. 207-209 °C
1 NMR (200 MHz, CDCI3): 5 7.9-7.7 (m, 3H), 7.4-7.0 (m, 9H), 4.7 (s, 2H), 3.0 (s, 3H), 2.6 (s, 3H). Mass (CI, i-Butane) m/z 421(M+ 100).
Example 98:
3-(2-FIuoro-4-methylsulfonylphenyI)-l-(4-fluorophenyl)-4-phenyl-2,5-dihydro-lH-2,5-
azoledione.

The title compound was prepared in 7% yield from N^-(4-fluorophenyl)-Nl-[2-(2-fluoro-4-methylsulfonylphenyl)-2-oxoethyl]-2-phenylacetamide (0.79 g, 1.58 mmol) using DBU (0.481 g, 1.58 mmol) according to the procedure described Example 2. m.p.: 198-200 T ^H NMR (200MHz, CDCI3): 5 7.8-7.1 (m, 12H), 3.1 (s, 3H). Mass (CI, i-Butane) m/z 439 ( M\ 100).

Claims:
1. A process for the preparation of compound of formula (I),
wherein R1 represents amino or substituted or unsubstituted groups selected from alkyl, alkylamino, acylamino, cycloalkyl, cyclicamino, carboethoxycarbonylalkyl, hydrazine, hydrazido, aminoacid residue, aryl, heteroaryl or -N=CR(NR)2 where R represents hydrogen or lower alkyl group; R represents halogen, hydroxy, cyano, nitro, azido, formyl, oximealkyl, thio or substituted or unsubstituted groups selected from amino, alkyl, alkoxy, hydrazine, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residue, aminoacid residuealkyl, acyl, carbonyloxyalkyl, haloalkyl, aminoalkyl, haloalkoxy, hydroxyalkyl, alkoxyalkyl, thioalkyl, alkylthio, alkylsulfmyl, alkylsulfonyl, aryl, aralkyl, aryloxy, aralkoxy, aryloxyalkyl, aralkoxyalkyl,- carboxamidoalkyl, carbonylaminoalkyl groups or when the groups -S(=0)m-R1 and R are present on adjacent carbon atoms, R and R together with atoms to which they are attached also form a substituted or unsubstituted 5-7 membered cyclic structure containing carbon atoms, a sulfur atom and optionally contain one or two heteroatoms selected from 0, S or N; R3 represents hydrogen, halogen atom, hydroxy, nitro, cyano, azido or substituted or unsubstituted groups selected from hydrazine, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residues, alkyl, alkoxy, hydroxyalkyl, alkoxyalkyl, acylamino or amino groups; R4 and R5 are same or different and independently represent hydrogen, halogen, hydroxy, cyano, nitro, thio, hydroxylamino, substituted or unsubstituted groups selected from alkyl, alkoxy, acyl, acyloxy, amino, hydrazino, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residues, aminoacyl, carboxyalkyl, carboxyalkenyl, aryl, aryloxy, aralkyl, aralkoxy, alkoxycarbonyl, aryloxycarbonyl, aralkoxycarbonyl, heteroaryl, heteroaryloxy, heteroaralkyl, heteroaralkoxy, heteroarylcarbonyl, heteroaryloxycarbonyl, heteroaralkylcarbonyl, heteroaralkoxycarbonyl, heterocyclylcarbonyl, aminocarbonyl, aminocarbonylalkyl, carbonylamino, cycloalkylacylamino, alkylaminoalkoxy, alkylaminoacyl, carboxylic acid or its derivatives, saturated or partially saturated or aromatic single or fused 5 to 7 membered

carbocycle ring or saturated or partially saturated or aromatic, single or fused 5 to 7 membered heterocycle ring; R6 represents hydrogen, halogen, hydroxy, amino, cyano, nitro, thio, hydroxylamino or unsubstituted or substituted groups selected from alkyl, alkoxy, carboxyalkyl; the furanone ring is fused with R4 wherever possible; R5 and 'R6 together represent =C(Ra)(Rb), where Ra and Rb are same or different and independently represent hydrogen, substituted or unsubstituted (C1-C6)alkyl or aryl; =0 or =NR7, where R7 represents hydrogen, aryl or heteroaryl group; X represents oxygen or NR8, where R8 represents hydrogen or substituted-or unsubstituted groups selected from (C1-C6)alkyl, aryl, aralkyl, heteroaryl, heteroaralkyl, aralkenoyl, aralkanoyl and m is an integer in the range of 0-2; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its regioisomers, its polymorphs, its pharmaceutically acceptable salts, its pharmaceutically acceptable solvates, which comprises: reacting a compound of formula (I-l)

where L1 represents B(0R)2, wherein R represents hydrogen or (C1-C6)alkyl and all other symbols are as defined above, with a compound of formula (1-2)

where L2 represents halogen atom or leaving group and all other symbols are as defined above, using a base and catalyst in the presence of solvent at a temperature and duration in the range of 0 °C to reflux temperature of the solvent and 0.5 to 76 h respectively.
2. The process as claimed in claim 1, wherein the solvent used in the reaction is selected from toluene, dimethylformamide, dioxane, tetrahydrofuran, isopropanol, ethanol, dimethylsulfoxide, dichloromethane, water or mixtures thereof
3. The process as claimed in claims 1 and 2, wherein the reaction is carried out in the presence of inert gases He, N2 or Ar.

4. The process as claimed in claims 1-3, wherein the catalyst used in the reaction is selected from bis(triphenyl phosphine)palladium(II)chloride, 1,4-bis(diphenyl phosphine butane)palladium (Il)chloride, bis(dibenzylideneacetone)paliadium(o), palladium acetate, palladium acetate-tri(o-tolyl)phosphine, bis(acetonitrile)palladium(II)chloride, palladium on carbon + triphenyl phosphine or tetrakis(triphenylphosphine)palladium(o).
5. The process as claimed in claims 1-4, wherein the base used in the reaction is selected from alkali metal carbonates, alkali metal bicarbonates, triethylamine, pyridine, dimethylaminopyridine (DMAP) or di-isopropylethylamine.
6. The process as claimed in claims 1-5, wherein the phase transfer catalyst used in the reaction is selected from tetraalkylammonium halide, benzyl triethylammonium halide, benzyl tributylammoriium halide, tetraalkylammonium bisulfate, benzyl triethylammonium bisulfate or benzyl tributylammonium bisulfate.
7. The process as claimed in claims 1-6, wherein the temperature and duration of the ^ reaction are maintained in the range of 30°C to reflux temperature and 6 to 24 h respectively.
8. A process for the preparation of compound of formula (I), where in all the symbols are as defined in claim 1, which comprises: reacting the compound of formula (1-3)

where L1 represents B(0R)2, wherein R represents hydrogen or (C1-C6)alkyl and all other symbols are as defined above in claim 1, with a compound of formula (1-4)
R4-L2 (1-4)
where L2 represents halogen atom or leaving group and R4 is as defined in claim 1, using a base and catalyst in the presence of solvent at a temperature and duration in the range of 0 °C to reflux temperature of the solvent and 0.5 to 76 h respectively.
9. The process as claimed in claim 8, wherein the solvent used in the reaction is selected
from toluene, dimethylformamide, dioxane, tetrahydrofuran, isopropanol, ethanol,
dimethylsulfoxide, dichloromethane, water or mixtures thereof

10. The process as claimed in claims 8 and 9, wherein the reaction is carried out in the presence of inert gases He, N2 or Ar.
11. The process as claimed in claims 8-10, wherein the catalyst used in the reaction is selected from bis(triphenyl phosphine)palladium(II)chloride, l,4-bis(diphenyl phosphine butane)palladium (Il)chloride, bis(dibenzylideneacetone)palladium(o), palladium acetate, palladium acetate-tri(o-tolyl)phosphine, bis(acetonitrile)paIladium(II)chloride, palladium on carbon + triphenyl phosphine or tetrakis(triphenylphosphine)palladium(o) and the amount of catalyst used is 1 to 10 mol %.
12. The process as claimed in claims 8-11, wherein the base used in the reaction is selected from alkali metal carbonates, alkali metal bicarbonates, triethylamine, pyridine, dimethylaminopyridine (DMAP) or di-isopropylethylamine and the amount of base used is 1 to 5 equivalents.
13. The process as claimed in claims 8-12, wherein the phase transfer catalyst used in the reaction is selected from tetraalkylammonium halide, benzyl triethylammonium halide, benzyl tributylammonium halide, tetraalkylammonium bisulfate, benzyl triethylammonium bisulfate or benzyl tributylammonium bisulfate and the amount of phase transfer catalyst used is 0.05 to 0.5 equivalents.
14. The process as claimed in claims 8-13, wherein the temperature and duration of the reaction are maintained in the range of 30°C to reflux temperature and 6 to 24 h respectively.
15. A process for the preparation of compound of formula (I), where in all the symbols are as defined in claim 1, which comprises: reacting the compound of formula (1-5)

where L represents halogen atom or leavmg group and all the symbols are as defined in claim 1, with a compound of formula (1-6)


where L1 represents B(0R)2 and all other symbols are as defined in claim 1, using using a base and catalyst in the presence of solvent at a temperature and duration in the range of 0 °C to reflux temperature of the solvent and 0.5 to 76 h respectively.
16. The process as claimed in claim 15, wherein the solvent used in the reaction is selected from toluene, dimethylformamide, dioxane, tetrahydrofuran, isopropanol, ethanol, dimethylsulfoxide, dichloromethane, water or mixtures thereof.
17. The process as claimed in claims 15 and 16, wherein the reaction is carried out in the presence of inert gases He, N2 or Ar.
18. The process as claimed in claims 15-17, wherein the catalyst used in the reaction is selected from bis(triphenyl phosphine)palladium(II)chloride, l,4-bis(diphenyl phosphine butane)palladium (Il)chloride, bis(dibenzylideneacetone)palladium(o), palladium acetate, palladium acetate-tri(o-tolyl)phosphine, bis(acetonitrile)palladium(II)chloride, palladium on carbon + triphenyl phosphine or tetrakis(triphenylphosphine)palladium(o).
19. The process as claimed in claims 15-18, wherein the base used in the reaction is selected from alkali metal carbonates, alkali metal bicarbonates, triethylamine, pyridine, dimethylaminopyridine (DMAP) or di-isopropylethylamine.
20. The process as claimed in claims 15-19, wherein the phase transfer catalyst used in the reaction is selected from tetraalkylammonium halide, benzyl triethylammonium halide, benzyl tributylammonium halide, tetraalkylammonium bisulfate, benzyl triethylammonium bisulfate or benzyl tributylammonium bisulfate.
21. The process as claimed in claims 15-20, wherein the temperature and duration of the reaction are maintained in the range of 30°C to reflux temperature and 6 to 24 h respectively.
22. A process for the preparation of compound of formula (I), where in all the symbols are as defined in claim 1, which comprises: reacting the compound of formula (1-7)


where L represents halogen atom or leaving groups and all other symbols are as defined in claim 1, with a compound of formula (1-8)
R4-L1 (1-8) where L1 represents B(0R)2 and all other symbols are as defined in claim 1, using a base and catalyst in the presence of solvent at a temperature and duration in the range of 0 °C to reflux temperature of the solvent and 0.5 to 76 h respectively.
23. The process as claimed in claim 22, wherein the solvent used in the reaction is selected from toluene, dimethylformamide, dioxane, tetrahydrofuran, isopropanol, ethanol, dimethylsulfoxide, dichloromethane, water or mixtures thereof
24. The process as claimed in claims 22 and 23, wherein the reaction is carried out in the presence of inert gases He, N2 or Ar.
25. The process as claimed in claims 22-24, wherein the catalyst used in the reaction is selected from bis(triphenyl phosphine)palladium(II)chloride, 1,4-bis(diphenyl phosphine butane)palladium (Il)chloride, bis(dibenzylideneacetone)palladium(o), palladium acetate, palladium acetate-tri(o-tolyl)phosphine, bis(acetonitrile)palladium(II)chloride, palladium on carbon + triphenyl phosphine or tetrakis(triphenylphosphine)palladium(o).
26. The process as claimed in claims 22-25, wherein the base used in the reaction is selected from alkali metal carbonates, alkali metal bicarbonates, triethylamine, pyridine, dimethylaminopyridine (DMAP) or di-isopropylethylamine.
27. The process as claimed in claims 22-26, wherein the phase transfer catalyst used in the reaction is selected from tetraalkylammonium halide, benzyl triethylammonium halide, benzyl tributylammonium halide, tetraalkylammonium bisulfate, benzyl triethylammonium bisulfate or benzyl tributylammonium bisulfate.
28. The process as claimed in claims 22-27, wherein the temperature and duration of the reaction are maintained in the range of 30°C to reflux temperature and 6 to 24 h respectively.

29. A process for the preparation of compound of formula (I), where in all the symbols are
as defined in claim 1, which comprises: reacting the compound of formula (II-2)

where L3 represents halogen atom and all other symbols are as defined in claim 1, with compound of formula (11-3)
where R and X are as defined in claim 1, using a base in the presence of solvent at a temperature and duration in the range of 0°C to 150°C and 2 to 50 h respectively.
30. The process as claimed in claim 29, wherein the base used in the reaction is selected from triethylamine, di-isopropylamine, di-isopropylethylamine, pyridine, piperidine, dimethylaminopyridine, l,8-diazabicyclo[5.4.0]undec-7-ene, lithium diisopropylamide, potassium bis-(trimethyl silyl)amide, Na2C03, K2CO3, NaOH, KOH, NaOMe, NaOEt, NaOiPr, t-BuOK,NaHorKH.
31. The process as claimed in claims 29 and 30, wherein the solvent used in the reaction is selected from tetrahydrofuran, N-methyl pyrrolidine, acetonitrile, propionitrile, acetone, 2-butanone, dimethylsulfoxide, dimethylformamide, dimethylamine, dichloromethane, CHCI3 or mixtures thereof.
32. The process as claimed in claims 29-31, wherein the inert gas used in the reactionis selected from He, N2 or Ar.
33. The process as claimed in claims 29-32, wherein the temperature and duration of the reacfion are maintained in the range of 20°C to reflux temperature and 2 to 20 h respecfively.
34. A process for the preparation of compound of formula (I), where in all the symbols are as defined in claim 1, which comprises: reacting the compound of formula (II-2)
where L3 represents halogen atom and all other symbols are as defined in claim 1, with compound of formula (II-3) where R4 and X are as defined in claim 1, using 2 equivalents of N, Nl-dicyclohexylcarbodiimide + 0.5 equivalents of DMAP or carboxymethylcellulose +

DMAP in the presence of solvent at a temperature and duration in the range of room temperature to reflux temperature of the solvent and 2 to 12 h respectively.
35. The process as claimed in claim 34, wherein the solvent used in the reaction is selected
from dichloromethane, CHCI3, benzene, toluene, xylene or mixtures thereof
36. A process for the preparation of compound of formula (I), where in all the symbols are
as defined in claim 1, which comprises: reacting compound of formula (II-4)

where L4 represents hydroxy or halogen atom and all other symbols are as defined in claim 1, using a base in the presence of solvent at a temperature and duration in the range of O°C to 150°C and 2 to 50 h respectively.
37. The process as claimed in claim 36, wherein the base used in the reaction is selected
from triethylamine, di-isopropylamine, di-isopropylethylamine, pyridine, piperidine,
dimethylaminopyridine, l,8-diazabicyclo[5.4.0]undec-7-ene, lithium diisopropylamide,
potassium bis-(trimethyl silyl)amide, Na2C03, K2CO3, NaOH, KOH, NaOMe, NaOEt, NaOiPr,
t-BuOK, NaH or KH.
38. The process as claimed in claims 36 and 37, wherein the solvent used in the reaction is
selected from tetrahydrofuran, N-methyl pyrrolidine, acetonitrile, propionitrile, acetone, 2-
butanone, dimethylsulfoxide, dimethylformamide, dimethylamine, dichloromethane, CHCI3 or
mixtures thereof
39. The process as claimed in claims 36-38, wherein the inert gas used in the reaction is
selected from He, N2 or Ar.
40. The process as claimed in claims 36-39, wherein the temperature and duration of the
reaction are maintained in the range of 20°C to reflux temperature and 2 to 20 h respectively.

41. An alternate process for the preparation of compound of formula (I), where in all the symbols are as defined in claim 1, which comprises: reacting compound of formula (II-4), where all the symbols are as defined in claim 1, with a compound of formula (II-5) where L"^ represents hydroxy or halogen atom and all other symbols are as defined in claim 1, using 2 equivalents of N, Nl-dicyclohexylcarbodiimide + 0.5 equivalents of DMAP or carboxymethylcellulose + DMAP in the presence of solvent at a temperature and duration in the range of room temperature to reflux temperature of the solvent and 2 to 12 h respectively.
42. The process as claimed in claim 41, wherein the solvent used in the reaction is selected from dichloromethane, CHCI3, benzene, toluene, xylene or mixtures thereof
43. The process for the preparation of compound of formula (I) where R1 represents amino group and m represents 2 and all other symbols are as defined in claim 1, which comprises: transforming a compound of formula (I), where R1 represents (C1-C6)alkyl, m represents 2 and all other symbols are as defined in claim 1, using Grignard reagent, nBuLi, LiNH2, LDA, trialkylborane or hydroxylamine-0 sulfonic acid and NaOAc in presence of the solvent at a temperature and duration in the range of of-78°C to the reflux temperature of the solvent and 2 to 72 h respectively.
44. The process as claimed in claim 43, wherein the solvent used in the reaction is selected from dioxane, diethylether, di-isobutylether, diphenylether, tetraydrofuran or mixtures thereof
45. The process as claimed in claims 43 and 44, wherein the inert gas used in the reaction is selected from Ar, N2 or He.
46. The process as claimed in claims 43-45, wherein the temperature and duration of the reaction are maintained at 0°C to reflux temperature of the solvent used and 2 to 24 h respectively.
47. A process for the preparation of compound of formula (I) where m represents 0 and all other symbols are as defined in claim 1, which comprises: reducing a compound of formula (I), where m represents 1 or 2 and all other symbols are as defined in claim 1, using reducing agent.
48. The process as claimed in claim 47, wherein the reducing agent used in the reaction is selected from LAH, HI, Bu3SnH, TiCl2, MeSiCl3, Nal, PCI3, H2-Pd-C, acetyl chloride, PPh3, t-BuBr, tris(dimethylamino)phosphine-l2 or diisobutyl aluminium hydride[(iBu)2AlH],
49. A process for the preparation of compound of formula (I) where m represents 1 or 2 and all other symbols are as defined in claim 1, which comprises: oxidizing a compound of formula

' (I), where m represents 0 and all other symbols are as defined in claim 1, using oxidizing agent in the presence of solvent at a temperature and duration in the range of 0 to ISO^^C and 0.5 to 24 h respectively.
50. The process as claimed in claim 49, wherein the oxidizing agent used in the reaction is selected from 30 % H2O2, m-CPBA, oxone (potassium peroxy monosulfate), NaI04, KMn04, sodiumperborate or magnesium monoperoxy phthalate hexahydrate.
51. The process as claimed in claims 49 and 50, wherein the solvent used in the reaction is selected from CHCI3, t-butanol, CH2CI2, acetone, CH3COOH or mixtures thereof
52. The process as claimed in claims 49-51, wherein the inert atmosphere in the reaction is maintained with He, N2 or Ar.
53. The process as claimed in claims 49-52, wherein the temperature and duration of the reaction are maintained at 30 to 120°C and 0.5 to 12 h respectively.
54. A process for the preparation of compound of formula (I),

wherein R1 represents amino or substituted or unsubstituted groups selected from alkyl, alkylamino, acylamino, cycloalkyl, cyclicamino, carboethoxycarbonylalkyl, hydrazino, hydrazido, aminoacid residue, aryl, heteroaryl or -N=CR(NR)2 where R represents hydrogen or lower alkyl group; R2 represents halogen, hydroxy, cyano, nitro, azido, formyl, oximealkyl, thio or substituted or unsubstituted groups selected from amino, alkyl, alkoxy, hydrazino, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residue, aminoacid residuealkyl, acyl, carbonyloxyalkyl, haloalkyl, aminoalkyl, haloalkoxy, hydroxyalkyl, alkoxyalkyl, thioalkyl, alkylthio, alkylsulfmyl, alkylsulfonyl, aryl, aralkyl, aryloxy, aralkoxy, aryloxyalkyi, aralkoxyalkyl, carboxamidoalkyl, carbonylaminoalkyl groups or when the groups -S(=0)m-R and R2 are present on adjacent carbon atoms, R1 and R2 together with atoms to which they are attached also form a substituted or unsubstituted 5-7 membered cyclic structure containing carbon atoms, a sulfur atom and optionally contain one or two heteroatoms selected from 0, S

or N; R3 represents hydrogen, halogen atom, hydroxy, nitro, cyano, azido or substituted or unsubstituted groups selected from hydrazino, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residues, alkyl, alkoxy, hydroxyalkyl, alkoxyalkyl, acylamino or amino groups; R"^ and R are same or different and independently represent hydrogen, halogen, hydroxy, cyano, nitro, thio, hydroxylamino, substituted or unsubstituted groups selected from alkyl, alkoxy, acyl, acyloxy, amino, hydrazine, hydrazinoalkyl, hydrazido, hydrazidoalkyl, aminoacid residues, aminoacyl, carboxyalkyl, carboxyalkenyl, aryl, aryloxy, aralkyl, aralkoxy, alkoxycarbonyl, aryloxycarbonyl, aralkoxycarbonyl, heteroaryl, heteroaryloxy, heteroaralkyl, heteroaralkoxy, heteroarylcarbonyl, heteroaryloxycarbonyl, heteroaralkylcarbonyl, heteroaralkoxycarbonyl, heterocyclylcarbonyl, . aminocarbonyl, aminocarbonylalkyl, carbonylamino, cycloalkylacylamino, alkylaminoalkoxy, alkylaminoacyl, carboxylic acid or its derivatives, saturated or partially saturated or aromatic single or fused 5 to 7 membered carbocycle ring or saturated or partially saturated or aromatic, single or fused 5 to 7 membered heterocycle ring; R6 represents hydrogen, halogen, hydroxy, amino, cyano, nitro, thio, hydroxylamino or unsubstituted or substituted groups selected from alkyl, alkoxy, carboxyalkyl; the furanone ring is fused with R4 wherever possible; R5 and R6 together represent =C(RA)(RB'), where Ra and Rb are same or different and independently represent

hydrogen, (C1-C6)alkyl or aryl; =0 or =NR7 , where R7 represents hydrogen, aryl or heteroaryl group; X represents oxygen and m is an integer in the range of 0-2; its derivatives, its analogs, its tautomeric forms, its stereoisomers, its regioisomers, its polymorphs, its pharmaceutically acceptable salts, its pharmaceutically acceptable solvates, which comprises: reacting compound of formula (II-1)
where R1, R2, R3, R4 and m are as defined above, with carbon monoxide and water, using acid and catalyst in the presence of solvent at a temperature and duration in the range of-78 to 300 °C and 2 to 80 h respectively.

55. The process as claimed in claim 54, wherein the catalyst used in the reaction is selected from PdCl2 Pd(0Ac)2 or (PPh3)PdCl2 and the amount of catalyst used is 2.0 mol %.
56. The process as claimed in claims 54 and 55, wherein the acid used in the reaction is selected from HCl, HBr or protic solvents.
57. The process as claimed in claim 54-57, wherein the temperature and duration of the reaction are maintained at 20 °C to reflux temperature of the solvent used and 2 to 80 h respectively.
58. A process for the preparation of compound of formula (I), where in all the symbols are as defined in claim 54, which comprises: reacting compound of formula (II-1)

where all the symbols are as defined in claim 54, with transition metal carbonyl complexes, using base in the presence of solvent at a temperature in the range of 30 to 300°C and 2 to 80 h.
59. The process as claimed in claim 58, wherein the transition metal carbonyl complexe used in the reaction is selected from Rh4(CO)4 or Rh4(CO)16.
60. The process as claimed in claim 58 and 59, wherein the solvent used in the reaction is selected from tetrahydrofuran, acetone, acetonitrile, benzene, toluene, EtOH, MeOH or mixtures thereof.
61. The process as claimed in claim 58-60, wherein the base used in the reaction is selected fromirialkyl amine or di-isopropyl ethylamine.
62. The process as claimed in claim 58-61, wherein the inert atmosphere in the reaction is maintained with He, N2 or Ar.
63. The process as claimed in claim 58-62, wherein the temperature of the reaction is
maintained at 50 to 150°C.

64. ,- The process as claimed in claim 58-63, wherein the pressure of the reaction is maintained at 20 to 300 atmosphere of pressure.