Ciprofloxacin is a quinolone that is quinolin-4(1H)-one bearing cyclopropyl, carboxylic acid, fluoro and piperazin-1-yl substituents at positions 1, 3, 6 and 7, respectively. It has a role as an antimicrobial agent, an antiinfective agent, a xenobiotic, an antibacterial drug, an EC 5.99.1.3 [DNA topoisomerase (ATP-hydrolysing)] inhibitor, a topoisomerase IV inhibitor, a DNA synthesis inhibitor and an environmental contaminant. It is a quinolone, a quinolinemonocarboxylic acid, an aminoquinoline, a N-arylpiperazine, a member of cyclopropanes, a quinolone antibiotic and a fluoroquinolone antibiotic. It is a conjugate base of a ciprofloxacin(1+). It is a tautomer of a ciprofloxacin zwitterion.