| abstract |
Novel antibacterially active 7-amino-1-(substituted cyclopropyl)-1,4-dihydro-4-oxo-3-quinolinecarboxylic acids of the formula <IMAGE> in which X1 and X2 can be identical or different and represent hydrogen or halogen, R1, R2 and R3 represent hydrogen, methyl, chlorine or fluorine, the radicals R1-R3 never all being identical, and R4 and R5, together with the nitrogen atom to which they are bonded, form a 5-membered or 6-membered heterocyclic ring which may be substituted. |