Influence of N substitution on antimycobacterial activity of ciprofloxacin

Ciprofloxacin analogs with various substitutions on the piperazine nitrogen were tested against several mycobacteria. In contrast to what has been found with other gram-positive and gram-negative bacteria, alkyl analogs such as N-isopropylciprofloxacin were shown to be significantly more active than ciprofloxacin. MICs of 0.125 microgram/ml against Mycobacterium tuberculosis were found.