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Updated: Jul 17, 2026

Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
Synthesis, Characterization, and Biological Evaluation of Co(II), Cu(II), and Ni(II) Complexes With
İsmail Yılmaz1, Müslüm Kuzu2, Hasan Almohammed3
1Department of Chemistry, Faculty of Engineering and Natural Sciences, Karabük University, Karabük, Türkiye.
Abstract:
This study reports the synthesis and characterization of two novel 2,2'-bipyridine-5,5'-dicarboxamide ligands (L1 and L2) and their corresponding Co(II), Cu(II), and Ni(II) complexes. The structures of the free ligands were verified using FTIR, NMR, UV-Vis, elemental analysis, and mass spectrometry, while the metal complexes were characterized through FTIR, MALDI-TOF MS, UV-Vis, and magnetic susceptibility techniques. Single-crystal X-ray diffraction was employed to elucidate the structure of L1. Biological evaluation against resistant bacterial strains identified Co-L2 as a potent antimicrobial agent, exhibiting a quantitative Minimum inhibitory concentration (MIC) of 500 μg/mL against E. coli, P. aeruginosa, and S. aureus. Furthermore, enzyme inhibition assays revealed that Ni-L2 was the most effective inhibitor for pancreatic lipase (IC50 = 0.36 μM) and butyrylcholinesterase (IC50 = 4.53 μM). In contrast, the free L2 ligand demonstrated the strongest inhibitory potency against acetylcholinesterase (IC50 = 0.479 μM). These findings underscore the influence of 5,5'-regiochemistry on the biological efficacy of bipyridine-based systems.
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