Synthesis, computational and UV–Vis absorption studies of novel sulfathiazole azo sulfonamides acting as potent antitubercular agents

Abstract

In this work, we have reported the synthesis of unprecedented sulfonamide azo dyes 4(a-j) by the diazo-coupling reaction of sulfathiazole with various coupling components. Different spectroscopic techniques, like FT-IR, NMR (1H and 13C), and HRMS, were used to precisely assess the structures of the target molecules. The UV–Vis absorption study was conducted using variety of organic solvents. Quantum chemical calculations, geometrical optimization, and molecular electrostatic potential regions of all sulfathiazole azo colorants were explored using (DFT)/B3LYP method. The efficacy of the synthesized dyes in combatting M. tuberculosis was examined using the MABA assay; the derivatives 4c and 4h demonstrated promising activity with MIC of 1.56 µg/mL. Further, in silico molecular docking study was performed to elucidate the interactions with enoyl-ACP reductase. Target compounds were screened for their antimicrobial activity using the broth microdilution method against two gram-positive, two gram-negative bacterial strains, and a fungal strain. The cytotoxic potential of the active compounds was assessed using the MTT assay against the Vero cell line.