Alchurak_2025_ChemistryOpen__e2500097

In this study, two new 2,2'-bipyridine-4,4'-dicarboxamide ligands, namely N4,N4'-bis(pyridin-2-ylmethyl)-[2,2'-bipyridine]-4,4'-dicarboxamide (L1) and N4,N4'-bis(piperidin-2-ylmethyl)-[2,2'-bipyridine]-4,4'-dicarboxamide (L2), and their Co(II), Cu(II), and Ni(II) complexes are synthesized and characterized. Elemental analysis, Fourier transform infrared spectroscopy, nuclear magnetic resonance, and mass techniques confirmed the structures of the synthesized compounds. The L1 structure is also determined by single-crystal X-ray diffraction. Antibacterial activities of ligands and metal complexes against resistant strains are investigated. The L2-Co complex demonstrates promising antibacterial qualities against these resistant strains, which is noteworthy. Additionally, enzyme inhibition studies are conducted to assess their potential therapeutic applications. The results show that the L2-Ni complex had the strongest inhibitory effect with IC(50) values of 1.35 microM for lipase enzyme, 4.33 microM for acetylcholinesterase enzyme, and 6.42 microM for butyrylcholinesterase.