NOVEL PYRIDONECARBOXYLIC ACID DERIVATIVES OR THEIR SALTS, AND ANTIBACTERIAL AGENTS CONTAINING THE SAME AS THEIR EFFECTIVE COMPONENTS

摘要

Pyridonecarboxylic acid derivatives represented by general formula (1) or their salts, wherein R1 represents hydrogen or a carboxyl protecting group; R2 represents hydroxy, lower alkoxy or optionally substituted amino; R3 represents hydrogen or halogeno; R4 represents hydrogen or halogeno; R5 represents optionally halogenated or substituted saturated cyclic amino; R6 represents hydrogen, halogeno, nitro or optionally protected amino; X, Y and Z may be the same or different and each represents nitrogen, -CH= or -CR7= wherein R7 represents lower alkyl, halogeno or cyano, provided that at least one of X, Y and Z represents nitrogen; and W represents nitrogen or -CR8= wherein R8 represents hydrogen, halogeno or lower alkyl.