Synthesis, characterization, and in vitro and in silico evaluation of anticancer activity and antioxidant activity of Cu(II), Ni(II), and Zn(II) metal complexes of a novel sulfonamide Schiff base

Abstract

In this study, sulfonamide-containing Schiff base (L) and its Cu(II), Ni(II) and Zn(II) complexes were synthesized for the first time. The structures of the compounds were characterized using elemental analysis, FT-IR, 1H NMR, 13C NMR and LC-MS spectroscopic techniques. The cytotoxic effects of the synthesized compounds on human breast, ovarian and colon cancer cells were evaluated using MCF-7, A2780, and Caco-2 cell lines. For this purpose, cells were treated with 1, 5, 25, 50 and 100 mu M concentrations of the compounds for 24 h. Changes in cell viability were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. In addition, the antioxidant activities of the compounds were revealed by measuring their DPPH free radical scavenging capacities. Following the study, molecular docking analyses were conducted to elucidate the binding mechanisms of the synthesized compounds to the active sites of target proteins for ovarian cancer (A2780; PDB ID: 4LV9) and oxidized form of Human Peroxiredoxin 2 (PDB ID: 5IJT). In vitro studies revealed that the complexes exhibited higher biological activity compared to the free ligand. These findings were also supported by data obtained from molecular docking and molecular dynamics simulations. In silico studies revealed that hydrogen bonding and steric interactions play a role in the interaction of the compounds with the target proteins.