Synthesis, characterization, DNA binding and cleavage activity of homoleptic zinc(II) β-oxodithioester chelate complexes

Abstract

New homoleptic zinc(II) complexes, [Zn(L)₂], where L = methyl-3-hydroxy-(3-pyridyl)-2-propenedithioate L1 1, and methyl-3-hydroxy-(4-pyridyl)-2-propenedithioate L2 2, have been synthesized and characterized by elemental (C, H, and N) analysis, ESI-MS, and (IR, UV–vis, NMR) spectroscopy; the structure of 1 has been deduced by X-ray crystallography. The DNA binding and cleavage activity of the complexes have been studied. The cleavage potential of pBR322 DNA by 1 and 2 has been checked. Complex 1, which contains nitrogen of the pyridine group in the 3-position enhances DNA cleavage potential in the presence of ascorbic acid; however, the complex is protective against DNA cleavage in the presence of DMSO or H₂O₂. Also, 1 causes cytotoxicity against the MCF-7 breast cancer cell line. The efficient cytotoxic activity and DNA cleavage ability of 1 in the presence of ascorbic acid shows its potential anticancer properties and the need for further investigations of its potential as an anticancer drug.

Keywords:

• Anticancer activity
• DNA Binding
• DNA Cleavage
• zinc(II) β-oxodithioester

Acknowledgments

New Delhi are gratefully acknowledged. The Department of Chemistry, CAS-UGC-I, Banaras Hindu University is acknowledged for the X-ray facilities. MV is thankful to UGC, New Delhi, India for financial support; UGC-CAS programme to Department of Zoology for infrastructural facilities and AKM (SRF) thanks to CSIR, New Delhi.