| abstract |
A quinolonecarboxylic acid compound represented by general formula (I), its salt or ester, and its medicinal use, wherein R represents C1 to C4 alkoxy or fluorinated C1 to C4 alkoxy; and Z represents hydroxyalkyl (C1 to C4)-substituted azetidin-1-yl, pyrrolidin-1-yl, piperidino, hexahydroazepin-1-yl, morpholino or hexahydro-1,4-oxazepin-1-yl. This compound is a highly useful antibacterial agent, because it has a potent antibacterial activity against gram-negative bacteria, is more potent than the conventional pyridonecarboxylic acid in the antibacterial activity against gram-positive bacteria, has an excellent antibacterial activity particularly against gram-positive bacteria including MRSA and neuroquinolone-resistant bacteria, and has an enhanced antibacterial activity in an acidic region. |