Designing and Exploration of the Biological Potentials of Novel Centrosymmetric Heteroleptic Copper(II) Carboxylates.

Copper(II) complexes with a general formula [Cu(3,4-FCHCHCOO)(L)], where L = 2-methylpyridine () and 3-methylpyridine (), are reported here. The FTIR spectra of the complexes confirmed the bridging bidentate coordination mode of the carboxylate ligand. The low (475 and 449 cm) and strong (727 & 725 cm) intensity bands in the FTIR spectra, due to Cu-N stretches and pyridyl ring vibrations, confirmed coordination of the 2-/3-methyl pyridine co-ligands in complexes and , respectively. A binuclear paddlewheel structural arrangement with a square pyramidal geometry was confirmed for copper atoms in the complexes via single-crystal X-ray analysis. The DPPH, OH radical, and α-amylase enzyme inhibition assays showed higher activities for the complexes than for the free ligand acid. The binding constant (K = 1.32 × 10 for and 5.33 × 10 for ) calculated via UV-VIS absorption measurements and docking scores (-6.59 for and -7.43 for ) calculated via molecular docking showed higher SS-DNA binding potential for compared to . Viscosity measurement also reflected higher DNA binding ability for than . Both complexes and (docking scores of -7.43 and -6.95, respectively) were found to be more active inhibitors than the free ligand acid (docking score of -5.5159) against the target α-amylase protein. This in silico study has shown that the herein reported compounds follow the rules of drug-likeness and exhibit good potential for bioavailability.