Synthesis of Coumarin-benzotriazole Hybrids and Evaluation of their Anti-tubercular Activity

Background: Tuberculosis is one of the top ranked airborne infectious diseases caused by the bacillus Mycobacterium tuberculosis with high mortality rate from a single infectious agent. In the present article, we aimed to synthesize oxadiazole-coumarin-triazole based small molecules and evaluate for their possible anti-mycobacterial activity. Method: Herein, we describe the facile synthesis of 5-((1H-benzo[d][1,2,3]triazol-1-yl)methyl)-1,3,4- oxadiazole-2-thiol-tethered substituted 4-(bromomethyl)-7-methyl-2H-chromen-2-one derivatives and evaluated for their anti-mycobacterial activity against H37Rv strain of M. tuberculosis. We also evaluated the cytotoxic effect of new compounds on normal cells. Results: Among the 14 novel oxadiazole-coumarin-triazole derivatives, 4-((5-((1H-benzo[d][1,2,3]triazol-1- yl)methyl)-1,3,4-oxadiazol-2-ylthio)methyl)-6-methoxy-2H-chromen-2-one (5f) displayed good antimycobacterial activity towards M. tuberculosis with an MIC value of 15.5 μM. Pyrazinamide was used as reference drug. Our investigation also revealed that, 5f is not cytotoxic to normal cells. Conclusion: In summary, the findings suggested that novel 1,3,4-oxadiazole coumarin-triazole hybrids are promising antimycobacterial agents against M. tuberculosis.