bis(acetato-O)(7-chloro-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylato-O(3),O(4))boron;Anhydride of diacetoxyboric and 1-cyclopropyl-6-fluoro-7-chloro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid;(4-acetyloxy-12-chloro-9-cyclopropyl-13-fluoro-6-oxo-3,5-dioxa-9-azonia-4-boranuidatricyclo[8.4.0.02,7]tetradeca-1(14),2(7),8,10,12-pentaen-4-yl) acetate
represent two classes of the most potent antibiotic against bacterial infections. In this study, the N-(amino)piperazine moieties from rifamycins were incorporated into the ciprofloxacin core according to the hybrid strategy, and different substituents were introduced to the N-(amino)piperazine to explore their influence to the anti-TB and antibacterial potency. Compounds 1k with cyclohexyl group (MIC = 0
4-dihydroquinoline-3-carboxylic acid and the literature protocol involving the preparation of boronchelatecomplex to facilitate nucleophilic aromatic substitution. All new fluoroquinolone derivatives were tested against two gram-positive as well as three gram-negative strains of bacteria. With the activity spectrum of the new derivatives being substantially narrower than that of ciprofloxacin, compounds were