NOVEL PYRIDONE CARBOXYLIC ACID DERIVATIVES

摘要

Pyridone carboxylic acid compounds or physiologically hydrolyzable esters thereof are provided which are represented by the formula: (I) wherein R1 is a lower alkyl, a halogen-substituted lower alkyl, a lower alkenyl, a cycloalkyl, or a substituted- or unsubstituted-phenyl group; R2 is a hydrogen atom, or a lower alkyl or an amino group; A is a nitrogen atom or the group C-X wherein X is a hydrogen or a halogen atom, or an alkoxy group; and Z is a group having the formula: (IV) wherein n is 1 or 2; R3 and R4 each represent a hydrogen atom or a lower alkyl group, with proviso that, if n is 2, one of R3 and R4 is a hydrogen atom; R5 and R6 each represent a hydrogen atom, or a hydroxy, a lower alkoxy or an amino group which is unsubstituted or substituted by a lower alkyl group, with proviso that one of R5 and R6 is a hydrogen atom; and R7 is a hydrogen atom or a lower alkyl group. The compounds of the present invention show potent and broad spectrum of antibacterial activities.