7-Aminoalkoxy-1-cyclopropyl-6-fluoro-1, 4-dihydro-4-oxoquinoline-3-carboxylic acid and their derivatives (8-10) were synthesized and their antibacterial activities were evaluated. Among them, compounds (10d-f, k) having an alkyl group at α-position of the amino group were found to have in vitro and in vivo antibacterial activity comparable to that of ciprofloxacin (1). Structure-activity relationship of these compounds was also stated.
