Synthesis of coumarin-thioether conjugates as potential anti-tubercular agents: Their molecular docking and X-ray crystal studies

Abstract

In this work, we report a series of 4-(2,6-dimethylphenyl)thio)methyl)-2H-chromen-2-one conjugates as promising leads to treat tuberculosis. Spectroscopic and other analytical methods were used to validate the synthesised compounds. The compounds were assessed for in vitro anti-tubercular activity with the H37Rv strain of Mycobacterium tuberculosis. Further, cytotoxicity studies were performed using Vero cells. Most of the synthesised conjugates were effective and displayed notable activity with MIC values in the range 0.39–12.5 µg/mL.The most diligent compound 6b (MIC = 0.39 µg/mL) was twofold more active than standard anti-TB drug Rifampin (0.8 µg/mL) and was comparable to Isoniazid (0.1 µg/mL). Compound 6f also displayed exemplary activity (MIC 0.78 µg/mL). Both compounds 6b and 6f possessed low levels of cytotoxicity, Molecular docking evaluation of the synthesised conjugates and 4DQU ligand demonstrated that the synthesised conjugates had higher C-score values that further supports the obtained results. It indicates compound 6b and 6f are promising lead compounds in search of novel antitubercular drug-like molecules.