In vitro activity of CP-74667 compared with four other fluoroquinolones.

CP-74667 is a new, novel C-7 diazabicyclo-fluoroquinolone. Its spectrum of activity includes the Enterobacteriaceae, most nonenteric Gram-negative bacilli, and Gram-positive cocci. Particularly high activity was demonstrated against Xanthomonas maltophilia (MIC50, 1 microgram/ml), Staphylococcus spp. (MIC50s, 0.06-0.12 micrograms/ml) and enterococci (MIC50s, 0.5-4 micrograms/ml). Several staphylococci resistant to ciprofloxacin had potentially susceptible range MICs for CP-74667, for example, less than or equal to 2 micrograms/ml. Fluoroquinolones with this C-7 modification appear promising and worthy of continued pharmaceutical investigation.