Design and Synthesis of New Bioactive 1,2,4-Triazoles, Potential Antitubercular and Antimicrobial Agents

Abstract

A New series of 1,2,4-triazole derivatives were synthesized using appropriate synthetic route and structures were confirmed by infrared spectroscopy, proton nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, mass spectroscopy and elemental analysis. Antimycobacterial activity of the synthesized compounds (1-12) was carried out and percent reduction in relative light units was calculated using luciferase reporter phage assay. Percent reduction in relative light units for isoniazid was also calculated. The test compounds showed significant antitubercular potential against Mycobacterium tuberculosis H37Rv and clinical isolates, S, H, R and E resistant M. tuberculosis, when tested in vitro. Compound 8 and 12 showed better antitubercular activity compared to reference isoniazid against M. tuberculosis H37Rv strain while compounds 5, 8 and 12 found superior to isoniazid against clinical isolates: S, H, R and E resistant M. tuberculosis. Synthesized compounds were also tested in vitro against representative bacterial and fungal strains. Tested compounds showed better antibacterial activities (minimum inhibitory concentration) against Gram-positive bacteria compared to Gram-negative. Compound 5 showed better antibacterial activity than ampicillin against B. subtilis. Compound 12 in the series displayed most potent antifungal activity, which was comparable to reference fluconazole against both the fungal strains.