Biofabricated Al2O3 nanoparticles as a recyclable heterogeneous catalyst for nicotinonitrile synthesis: antimicrobial activity, molecular docking and ADMET assessment

An efficient and environmentally benign Al2O3 nanoparticle-catalyzed protocol was developed for the synthesis of nicotinonitrile derivatives under mild reaction conditions using an ethanol-water solvent system. The Al2O3 nanoparticles were synthesized via a green approach employing Coccinia indica leaf extract and characterized by XRD, SEM, EDS, FTIR, and BET analyses. The developed catalytic protocol afforded excellent yields (88-96%) within short reaction times (18-40 min), demonstrating a broad substrate scope, high catalytic activity, and excellent recyclability. The synthesized nicotinonitrile derivatives were further evaluated for their antimicrobial activity against S. aureus, B. subtilis, P. aeruginosa, and E. coli, exhibiting promising antibacterial efficacy. Molecular docking studies against the bacterial DNA gyrase B enzyme further supported their potential antimicrobial mechanism, while in silico ADMET analysis indicated favorable drug-likeness and toxicity profiles. Overall, this study demonstrates a sustainable nanocatalytic strategy for the efficient synthesis of biologically active nicotinonitrile derivatives.