A Tridentate Cu(II) Complex with a 2-(4′-Aminophenyl)Benzothiazole Derivative: Crystal Structure and Biological Evaluation for Anticancer Activity

Abstract

Herein, the synthesis, structural characterization and in vitro biological evaluation of a novel Cu(II) complex with the 2-(4-aminophenyl)benzothiazole pharmacophore conjugated with the (2-pyridinyl)methylamino chelating moiety is reported for the first time. A full characterization of the Cu(II) complex was conducted by X-ray crystallography, EPR, IR, elemental and MS analysis, and its binding to CT-DNA was investigated by UV-vis spectroscopy, ethidium bromide competition studies, circular dichroism, viscometry and thermal denaturation. The data clearly indicate that the Cu(II) complex interacts with CT-DNA via intercalation, registering a difference compared to previously reported Pt(II) and Pd(II) analogues. To evaluate the anticancer activity of the complex, a series of in vitro experiments against breast, glioblastoma, prostate and lung cancer cell lines along with healthy fibroblasts were implemented. Cytotoxicity, cellular uptake, intracellular ROS production, cell cycle and apoptosis analysis revealed an increased anticancer activity towards breast cancer cells that is accompanied by an induction in intracellular ROS levels and a significant G2/M arrest followed by apoptosis.