Antitumor activity and DNA-binding investigations of the Zn(II) and Cu(II) complexes with isoeuxanthone

Abstract

Two new complexes ZnL2 (1) and CuL2 (2) (here, HL=isoeuxanthone) have been synthesized and characterized by elemental analyses, molar conductance, infrared spectra (IR), 1H-NMR and UV-Vis measurements. The interactions of them with calf thymus DNA (ct DNA) have been investigated by absorption spectroscopy, fluorescence spectroscopy, circular dichroism spectroscopy and viscosity measurements. Experimental results revealed an intercalative interaction with DNA for the complexes; furthermore the binding affinity of 2 is higher than that of 1 according to the calculated binding constant values. In addition, they were evaluated for their cytotoxic activities toward human esophageal cancer (ECA109) and human gastric cancer (SGC7901) cells by MTT assay. Both of them showed significant cytotoxic potency. © 2009 Pharmaceutical Society of Japan.