DNA-binding and cleavage activity of a new alkoxo and acetate-bridged dinuclear copper(II) complex

A new copper complex, [Cu2L(OAc)(CH3OH)] center dot CH3OH, where H3L is 1,3-bis (5-methylsalicylideneimino)propan-2-ol, has been synthesized and characterized by single-crystal X-ray diffraction, IR, ES-MS, and UV-Vis techniques. The coordination polyhedra of copper(II) can be described as a tetrahedron and a planar quadrilateral. The interaction between the complex and calf thymus DNA/DNA was investigated by UV-Vis, fluorescence, circular dichroism spectra, and viscosity. All the results show that the interaction mode of the complex with DNA is intercalative with a binding constant of 1.16 x 10(5) (mol L-1)(-1) and linear Stern-Volmer quenching constant of 4.89 x 10(2) (mol L-1)(-1), respectively. Agarose gel electrophoresis exhibits that the complex can transform supercoiled to nicked form and exhibits effective DNA-cleavage activity via hydrolytic-cleavage mechanism.