Conventional and microwave-assisted synthesis of new indole-tethered benzimidazole-based 1,2,3-triazoles and evaluation of their antimycobacterial, antioxidant and antimicrobial activities

A new series of triheterocycles containing indole–benzimidazole-based 1,2,3-triazole hybrids have been synthesized in good yields via a microwave-assisted click reaction. All the compounds were characterized by IR, \(^{1}\hbox {H}\) NMR, \(^{13}\hbox {C}\) NMR and mass spectroscopy and were evaluated for their in vitro antitubercular activity against the Mycobacterium tuberculosis H37Rv strain. Compounds 4b, 4h and 4i displayed highly potent antitubercular activity with MIC 3.125–6.25 \(\upmu \hbox {g}/\hbox {mL}\). The antioxidant potential was evaluated using 2,2-diphenyl-1-picryl hydrazine and \(\hbox {H}_{2}\hbox {O}_{2}\) radical scavenging activity, and compounds 4e,4f and 4g showed excellent radical scavenging activity with \(\hbox {IC}_{50}\) values in the range of 08.50–10.05 \(\upmu \hbox {g}/\hbox {mL}\). Furthermore, the compounds were evaluated for antimicrobial activity against numerous bacterial and fungal strains, and compounds 4b, 4c and 4h were found to be the most promising potential antimicrobial molecules with MIC 3.125–6.25 \(\upmu \hbox {g}/\hbox {mL}\).