Two new derivatives from the ciprofloxacin fluoroquinoline family, 7-chloro-1-cyclopropyl-6- fluoro-1, 4-dihydro-4-oxo-quinoline-3-methylcarbamate and 1-cyclopropyl-7-(4-ethyl-1- piperazinyl)-6-fluoro-1, 4-dihydro-(3-oxopyrazolo)[4, 3-c] quinoline, were synthesised, tested for antibacterial activity and crystallised. Their molecular and crystal structures were determined. Tests in vitro reveal lower activities than for ciprofloxacin. Characteristic ...