Evaluation of antimycobacterial and DNA gyrase inhibition of fluoroquinolone derivatives

Abstract

The antimycobacterial activity (both in vitro and in vivo) and DNA gyrase inhibition of newly synthesized fluoroquinolone derivatives were tested against Mycobacterium tuberculosis H₃₇Rv and Mycobacterium smegmatis, respectively. Among the synthesized compounds, compound F11 was found to exhibit the most potent in vitro antimycobacterial activity with a MIC value of 0.78 μg/ml, and a selectivity index of more than 80 while not being cytotoxic to the Vero cell line up to 62.5 μg/ml. When evaluated for in vivo antimycobacterial activity, compound F11 demonstrated a paramount decrease of bacterial load in lung and spleen tissues compared to the control and better than the standard drug ciprofloxacin.