An 8-methoxyquinolonecarboxylic acid derivative represented by general formula (I), and optical isomers, pharmaceutically acceptable salts and hydrates thereof, wherein R₁ represents hydrogen, lower alkyl, phenylalkyl or an in vivo hydrolyzable ester residue; R₂ represents hydrogen or methyl; and n represents an integer of 0 or 1. This derivative has a wide antimicrobial spectrum based on the activity potentiated in vitro and in vivo against gram-positive bacteria while retaining the potent antibacterial activity of the conventional quinolonecarboxylate bactericides against gram-negative bacteria. Since it scarcely has problematic side effects and is reduced in toxicity, it is promising as a bactericide having more excellent clinical effects.
通式(I)代表的
8-甲氧基喹啉羧酸衍
生物及其光学异构体、药学上可接受的盐和
水合物,其中 R₁ 代表
氢、低级烷基、
苯基烷基或体内可
水解的
酯残基;R₂ 代表
氢或
甲基;n 代表 0 或 1 的整数。根据体外和体内对革兰氏阳性菌的增效活性,这种衍
生物具有广泛的抗菌谱,同时保留了传统
喹啉羧酸盐
杀菌剂对革兰氏阴性菌的强效抗菌活性。由于它几乎没有副作用,毒性也较低,因此有望成为一种临床效果更佳的
杀菌剂。