Antituberculosis agents. VI. Activity of a new ciprofloxacin derivative against Mycobacterium avium and some drug-resistant strains of Mycobacterium tuberculosis.

The in vitro antimycobacterial activity of a new quinolone derivative, 1a containing 2-(2-furyl)-2-oxoethyl group at N-4 position of piperazine ring of Ciprofloxacin was tested for efficacy in vitro in TB-infected macrophage model (EC90 = 3.25 micrograms/ml and EC99 > 12.5 micrograms/ml). The MIC values of 1a were determined against M. tuberculosis strains resistant to Isoniazid (MIC = 1.56 micrograms/ml), Rifampin (MIC = 1.56 micrograms/ml), Ethambutol (MIC = 0.78 microgram/ml), Kanamycin (MIC = 0.78 microgram/ml) and Ciprofloxacin (MIC > 25 micrograms/ml). Furthermore, the MIC and selectivity index (SI) of 1a were evaluated against M. avium. Also, in this study the minimum bactericidal concentration (MBC) of 1a was determined against M. tuberculosis H37Rv (MBC = 6.25 micrograms/ml) and strain resistant to Rifampim (MBC = 25 micrograms/ml) and Isoniazid (MBC = 25 micrograms/ml).