Design, Synthesis of Novel Phenyldiazene-Linked Benzimidazole– Triazole Hybrids and Their Antimicrobial Activity, Molecular Docking Studies

Abstract

: A series of novel benzimidazole–1,2,3-triazole hybrids 7(a–o) were synthesized via multistep reactions involving diazotization, propargylation, cyclization, and Copper-catalyzed azide-alkyne cycloaddition. The synthesized compounds were characterized by FT-IR, ¹H NMR, ¹³C NMR, and mass spectral analyses. The CuAAC reaction was optimized using various solvent systems, where tBuOH/H₂O (1:1) afforded the best yields. The compounds were screened for antibacterial and antifungal activities against selected microbial strains. Structure–activity relationship studies revealed that fluoro-substituted derivatives exhibited enhanced activity against Gram-positive bacteria and fungal strains, while methoxy-substituted compounds showed better activity against Gram-negative bacteria. Among the synthesized derivatives, compounds 7b and 7f displayed the most promising antimicrobial activity.