In vitro activities of irloxacin and E-3846, two new quinolones.

Irloxacin and E-3846 are two new fluorinated quinolones. We evaluated the activities of these antimicrobial agents, ciprofloxacin, ofloxacin, enoxacin, pefloxacin, norfloxacin, and nalidixic acid against 1,161 bacterial strains. Ciprofloxacin was the most active quinolone. Irloxacin did not show great activity. The activity of E-3846 against gram-negative bacteria was similar to those of ofloxacin and pefloxacin, and E-3846 was the most active quinolone against gram-positive bacteria and anaerobes.