title: In vitro activity of A-56619 and A56620, two new aryl-fluoroquinolone antimicrobial agents.
abstract: The in vitro antimicrobial activity of two new aryl-fluoroquinolone antibiotics, A-56619 and A-56620, was compared with those of norfloxacin and several other antibiotics against 448 bacterial isolates. A-56620 was the most active agent tested. The usual 90% MIC of A-56620 was less than or equal to 2 micrograms/ml, except for enterococci, gentamicin-resistant Serratia marcescens, and gentamicin-resistant Pseudomonas aeruginosa, for which the 90% MIC was 4 micrograms/ml. A-56619 and norfloxacin were generally severalfold less active than A-56620. Cross resistance was observed between the quinolone antibiotics and other unrelated antibiotic classes.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000890:Anti-Infective Agents; D002939:Ciprofloxacin / Q000031:analogs & derivatives*; D004352:Drug Resistance, Microbial; D004755:Enterobacteriaceae / Q000187:drug effects; D024841:Fluoroquinolones; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D009643:Norfloxacin / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology*; D011804:Quinolines / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D010879:Piperazines; D011804:Quinolines; D002939:Ciprofloxacin; C047225:difloxacin; D009643:Norfloxacin; C047224:sarafloxacin