Synthesis, Crystal Structure and DNA-Binding Studies of the Complex [Co(C10H9N2O4)2] • 3H2O

A novel binuclear Cobalt(II) complex with N-(2-propionic acid)-salicyloyl hydrazone (C10H10N2O4, H3L) was prepared and characterized. The crystal structure of [Co(C10H9N2O4)(2)] center dot 3H(2)O was determined by X-ray single-crystal diffractometry. The Co2+ ion is six-coordinated by the carboxyl and acyl O atoms and azomethine N atoms of two tridentate N-(2-propionicacid)-salicyloyl hydrazone ligands, which form two stable five-numbered rings sharing one side in the keto form. The coordination environment around the Co2+ ion might be described as a distorted octahedron. Abundant hydrogen bonds of the types O-H center dot center dot center dot N and O-H center dot center dot center dot O between the water molecules and ligands not only form the three-dimensional network, but also provide an extrastability for the crystal. The complex was studied for the interaction with calf thymus DNA by electronic absorption titration and emission titration. The results show that the complex is bound to calf thymus DNA mainly by intercalation.