Optimization of N-benzyl-5-nitrofuran-2-carboxamide as an antitubercular agent.

The optimization campaign for a nitrofuran antitubercular hit (N-benzyl-5-nitrofuran-2-carboxamide; JSF-3449) led to the design, synthesis, and biological profiling of a family of analogs. These compounds exhibited potent in vitro antitubercular activity (MIC = 0.019-0.20 μM) against the Mycobacterium tuberculosis H37Rv strain and low in vitro cytotoxicity (CC50  = 40->120 μM) towards Vero cells. Significant improvements in mouse liver microsomal stability and mouse pharmacokinetic profile were realized by introduction of an α, α-dimethylbenzyl moiety. Among these compounds, JSF-4088 is highlighted due to its in vitro antitubercular potency (MIC = 0.019 μM) and Vero cell cytotoxicity (CC50  > 120 μM). The findings suggest a rationale for the continued evolution of this promising series of antitubercular small molecules.