Patent ID: 7153854

Claim:
A compound of the formula I or a pharmaceutically acceptable salt thereof, or a prodrug thereof: wherein R 1 is a phenyl, a pyrrolyl, an isooxazolyl, a furanyl, a thienyl, a lower alkyl optionally substituted by a lower alkoxy, a piperazinyl or a morpholinyl, wherein a lower alkoxy is optionally substituted by a cyclo(lower)alkyl or a pyridinyl, R 2 is —(CH2)n-R 7 , wherein n is an integer which may range from 2 to 5, and R 7 is a carboxy or an esterified carboxy, and R 7 is (1) a hydrogen, (2) a substituted aryl or an unsubstituted aryl, (3) a substituted heterocyclic group or an unsubstituted heterocyclic group, (4) a carboxy, a protected carboxy or CONR 10 R 11 , (5) an acyl or a halocarbonyl, (6) a cyano, (7) an amino, a protected amino, a or mono- or di(lower)alkylamino, (8) a hydroxy, an aryloxy, an acyloxy or a lower alkyl optionally substituted by a hydroxy or an acyloxy, (9) a lower alkylthio, a lower alkylsulfinyl or a lower alkylsulfonyl, or (10) —O—R 12 , R 3 is (1) a phenyl optionally substituted by a lower alkyl, a cyclo(lower)alkyl, a lower alkoxy, a halogen, a cyano, or a carbamoyl; or (2) a pyridinyl substituted by a lower alkyl, a cyclo(lower)alkyl, a lower alkoxy, a carbamoyl or a halogen, R 4 is a hydrogen, a halogen, a cyano, a carbamoyl, an acyl, a thiocyanate, a lower alkylthio, a lower alkenyl, a hydroxyl(lower)alkyl, a trihalo(lower)alkyl, or a lower alkyl, R 10 and R 11 each independently represents a hydrogen, a lower alkylsulfonyl, a heterocyclic group, or a lower alkyl optionally substituted by a hydroxy, an alkoxy, a sulfo, a carboxy, a protected carboxy or —R 17 or alternatively R 10 and R 11 , together with a nitrogen atom to which they are attached, represent a N-containing heterocyclic group, and R 12 and R 17 are each independently a group derived from a protected sugar or an unprotected sugar by removal of the hydroxy group therefrom.