Synthesis, characterization, DNA binding and cleavage studies of Ru(II) complexes containing oxime ligands

The Ru(II) precursors, [RuHCl(CO)(EPh3)3] (E = P or As) when reacted with some well known monoxime and dioxime ligands in ethanolic solution afforded the new complexes of the types [RuCl(CO)(EPh3)2L1], [RuH(CO)(EPh3)2L2] and [RuCl(CO)(EPh3)2L3] ((H1L1) = diacetylmonoxime, (H1L2) = dimethylglyoxime and (H2L3) = benzoiloxime). The ligands coordinated in a bidentate chelate mode forming a five membered chelate ring. The molecular structures of two of the complexes have been determined by single crystal X-ray diffraction study. The structural determination confirms the deprotonation of the oxime function. Examination of all the complexes by cyclic voltammetry showed the occurrence of some quasi-reversible redox reactions owing to changes in the oxidation state of the central metal atoms. Structural assignments are supported by combination of IR, UV–Vis, 1H NMR and elemental analyses. In addition, the DNA binding properties and cleavage efficiency of new complexes have been tested.