QUINOLONE- OR NAPHTHYRIDONECARBOXYLIC ACID DERIVATIVE AND SALT THEREOF, PHARMACEUTICAL COMPOSITION CONTAINING THEM AND THEIR USE

摘要

This invention relates to a novel quinolone- or naphthyridone-carboxylic acid derivative or its salt useful as an antibacterial agent, said derivative has a substituent represented by the following formula at the 7 position: wherein preferably R<3> represents at least one member selected from the group consisting of a hydrogen atom, a halogen atom, a substituted or unsubstituted lower alkyl, lower alkoxy or lower alkylthio group, a nitro group, a cyano group, a protected or unprotected hydroxyl group and a protected or unprotected amino group; R<4> represents a hydrogen atom, a substituted or unsubstituted lower alkyl group, a lower alkylidene group and a group forming a cycloalkane ring together with the carbon atom to which R<4> is bonded; and R<5> represents a hydrogen atom or a substituted or unsubstituted lower alkyl or cycloalkyl group.