Synthesis, Crystal Structure, DNA Binding and Catalytic Activities of a New Unsymmetrical Macrocyclic Dinuclear Zn(II) Complex

An unsymmetrical macrocyclic dinuclear Zn(II) complex, [Zn-2(H0.5L)(OAc)](ClO4)(1.5) (1, H2L is the condensation product between 2, 6-diformyl-4-methylphenol and diethylenetriamine), was obtained and characterized by IR spectrum, elemental analysis and X-ray single-crystal diffraction. The complex crystallizes in monoclinic, space group P2(1)/c with a = 16.784(2), b = 19.474(3), c = 10.3364(13) angstrom, beta = 92.923(2)degrees, V = 3374.1(7) angstrom(3), Z = 4, D-c = 1.672 g/cm(3), F(000) = 1740, mu = 1.651 mm(-1), the R = 0.0609 and wR = 0.1696 for 4745 observed reflections (I > 2 sigma(I)). The interactions of the complex with DNA have been measured by electrochemical studies, UV spectroscopy and viscosity experiment. The interactions of the complex with calf thymus DNA were studied by UV-vis spectra and the binding constant is 1.58 x 10(4) mol.L-1. The phosphate hydrolysis catalyzed by the complex was investigated using 4-nitrophenyl phosphate (NPP) as the substrate; the observed first order rate constant value is 3.0 x 10(-4) s(-1).