Synthesis and antitubercular evaluation of imidazo[2,1-b][1,3,4]thiadiazole derivatives

Abstract

In the present study, a series of imidazo[2,1-b][1,3,4]thiadiazole derivatives 5(a–j) were synthesized and characterized by IR, 1H NMR, 13C NMR and mass spectral technique. The compounds were evaluated for their in vitro antitubercular activity against Mycobacterium tuberculosis H37Rv strain by using Alamar Blue susceptibility test as part of the TAACF TB screening program under direction of the US National Institutes of Health, the NIAID division. Among the tested compounds, 2-(1-methyl-1H-imidazol-2-yl)-6-(4-nitrophenyl)imidazo[2,1-b][1,3,4]thiadiazole (5f) has shown the highest (98%) inhibitory activity with MIC of 3.14 μg/ml as compared to other tested compounds. Further, some potent compounds were also assessed for their cytotoxic activity against a mammalian Vero cell line using MTT assay. The results reveal that these compounds exhibit anti-tubercular activity at non-cytotoxic concentrations.

Keywords

• Imidazo[2,1-b][1,3,4]thiadiazole synthesis
• Mycobacterium tuberculosis
• Antitubercular activity