The Selectfluor-mediated approach toward the synthesis of methylene-tethered arylsulfonation and benzotriazolation of imidazopyridines has been described. The reaction involves imidazopyridine, aryl sulfinate, or benzotriazole and dimethyl sulfoxide (DMSO) in the presence of Selectfluor, where DMSO acts as a one-carbon synthon. The protocol has been extended to the methylene-tethered arylsulfonation and benzotriazolation of β-naphthols. The mechanistic insights show that the intermediate 3-((methylthio)­methyl)-2-phenylimidazo­[1,2-a]­pyridine is generated from imidazopyridine, DMSO, and Selectfluor. The nucleophilic displacement by the aryl sulfinate salt or benzotriazole on the intermediate afforded the product.

Novel inhibitors are needed to tackle tuberculosis. Herein, we report the 3‐aryl‐substituted imidazo[1,2‐a]pyridines as potent antituberculosis agents. A small library of 3‐aryl‐substituted imidazo[1,2‐a]pyridines was synthesized using direct arylation, followed by nitro reduction and finally Pd‐catalyzed C−N coupling reactions. The compounds thus obtained were evaluated against Mycobacterium tuberculosis H37Rv. Compound 26 was identified as an antituberculosis lead with a minimum inhibitory concentration of 2.3 μg/ml against M. tuberculosis H37Rv. This compound showed a selectivity index of 35. The docking of 26 in the active site of the M. tuberculosis cytochrome bc1 complex cytochrome b subunit (Mtb QcrB) revealed key π–π interactions of compound 26 with the Tyr389 and Trp312 residues of Mtb QcrB.

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