| abstract |
The present invention provides an agent which exhibits excellent antibacterial activity, low toxicity, improved bioavailability, and low binding rate to serum proteins. The present invention is directed to a pyridonecarboxylic acid derivative represented by formula (1): n nor a salt thereof, wherein R 1 represents a methyl group, a fluorine atom, or a chlorine atom; R 2 represents a hydrogen atom or a lower alkyl group; R 3 represents an isopropyl group or a tert-butyl group; R 4 represents a methyl group or a halogen atom; and R 5 represents a fluorine atom or a chlorine atom. The present invention is also directed to an antibacterial agent and a medicament containing the derivative or the salt thereof as an active ingredient. |