Patent ID: 7459451

Claim:
A compound of formula (I): in which R 1 is (1) lower alkyl optionally substituted by halogen, cyclo(lower)alkyl, lower alkoxy, hydroxy, protected hydroxy, cyclo(lower)alkyloxy, aryloxy, hydroxyimino, carbamoyloxy optionally substituted by lower alkyl, or substituted or unsubstituted heterocyclyl, wherein said lower alkoxy is optionally substituted by cyclo(lower)alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted heteroaryl, (2) lower alkenyl optionally substituted by cyano or carbamoyl optionally substituted by aryl which may have halogen, (3) cyclo(lower)alkyl, (4) acyl, (5) cyano, (6) substituted or unsubstituted aryl, or (7) substituted or unsubstituted heteroaryl; R 2 is hydroxy, protected hydroxy, cyano, carboxy, hydroxyimino(lower)alkyl,—CONR 6 R 7 or -(A 1 )p-X-A 2 -R 5 , wherein p is 0 or 1 A 1 is (C 1 -C 2 )alkylene or —CH═CH—; A 2 is a divalent heterocyclic group, or —(CH 2 ) n — or —(CH═CH) m —, wherein n is integer which may range from 1 to 6 and m is integer which may range from 1 to 3; X is single bond, —CH 2 — or —O—, and R 5 is protected hydroxy, cyano, carboxy, protected carboxy, hydroxyimino(lower)alkyl, or —CONR 6 R 7 wherein R 6 is hydrogen or lower alkyl, and R 7 is hydrogen or —(CH 2 ) q —Y—R 8 , wherein q is 0, 1, 2 or 3, Y is bond, —O—, or —CH(R 9 )—CH 2 —, wherein R 9 is lower alkyl, carboxy or protected carboxy, and R 8 is (1) lower alkyl, (2) substituted or unsubstituted aryl, (3) substituted or unsubstituted heteroaryl, (4) substituted or unsubstituted heterocyclyl, or (5) substituted or unsubstituted cyclo(lower)alkyl), or alternatively R 6 and R 7 , together with the nitrogen atom to which they are attached, represent substituted or unsubstituted azaheterocyclyl group; R 3 is (1) substituted or unsubstituted aryl, (2) substituted or unsubstituted heteroaryl, (3) substituted or unsubstituted heterocyclyl, (4) cyclo(lower)alkyl, or (5) lower alkyl optionally substituted by (a) cyclo(lower)alkyl, (b) substituted or unsubstituted heterocyclyl, (c) substituted or unsubstituted aryl, or (d) substituted or unsubstituted heteroaryl; and R 4 is lower alkyl, or a pharmaceutically acceptable salt thereof.