Synthesis, spectroscopic characterization, crystal structure and biological properties of novel co-crystal copper(II) complex containing dioxime ligand

Abstract

The title compound, co-crystal [(aqua) (1E,1′E,2E,2′E)-2,2′-(propane-1,3-diylbis(azaneylylidene)) bis(2-phenylacetaldehyde)dioximato] copper(II)chlorate, [Cu(HL1)ClO4]3, was synthesized from 1,3-diaminopropane and isonitrosoacetophenone. Its molecular and crystal structures were determined by single crystal X-ray analysis. The asymmetric unit of the newly synthesized co-crystal contains three crystallographically independent copper complex molecules and three uncoordinated chlorotetraoxide anions. The DNA binding activity of the Cu(II) complex was carried out by absorption spectra measurements and fluorescence spectroscopy. The results revealed that the binding mode of the complex with DNA is via minor groove. The concentration and time dependent DNA cleavage studies including cleavage mechanism of the complex were performed by employing gel electrophoresis assay, where the complex has been found to cleave supercoiled DNA with high efficiency. Topoisomerase I and IIα inhibition assays with Cu(II) complex were performed and complex showed strong inhibition against both enzymes. The cytotoxic activity of the complex was performed on human cell lines, lung carcinoma cell line (A549), colorectal adenocarcinoma cell line (HT29), hepatocellular carcinoma cell line (HepG2), breast cancer cell line (MDA-MB-231) and prostate cancer cell lines (LnCaP) by MTT assay. Annexin V, MMP and ROS assays were also performed. The complex was exhibited significant in vitro cytotoxicity against HepG2 and LnCaP.