摘要 |
New 6,7-disubstituted-1-cyclopropyl-1,4-dihydro-4-oxo-1,8-naphthyridine-3- carboxy lic acids of the formula (I) <IMAGE> in which X represents halogen or nitro and A represents <IMAGE> wherein R1, R2, R3 and R4 are defined hereinbelow are disclosed as well as their usefulness as antibacterial agents. |