Synthesis, crystal structure and biological activities of dehydroacetic acid complexes of Ru(II) and Ru(III) containing PPh3/AsPh3

A series of Ru(II) and Ru(III) complexes of the types [RuX(CO)(EPh3)2L] (X = H, E = P; X = Cl, E = P or As) and [RuX2(EPh3)2L] (X = Cl, E = P or As; X = Br, E = As, L = monoanion of dehydroacetic acid) have been synthesized in order to explore their biological activities, such as DNA-binding and antibacterial activity. The complexes were characterized by analytical and spectroscopic techniques. The crystal and molecular structure of [RuCl2(AsPh3)2(L)] has been determined by single crystal XRD. The cyclic voltammograms of the complexes in acetonitrile displayed either quasi-reversible or irreversible redox couples based on the metal centre. The ligand, dehydroacetic acid (DHA) and its metal complexes were tested against five pathogenic bacteria. Absorption titration and cyclic voltammetric studies revealed that the complexes interact with Herring Sperm ds DNA through different binding modes to different extents.

Six new Ru(II)/Ru(III) complexes of dehydroacetic acid (DHA) were synthesized and characterized. Single crystal X-ray structure determination of one of the Ru(III) complexes authenticated the monobasic bidentate (O,O) coordination of the DHA ligand. The complexes showed convincing antibacterial properties. The DNA-binding ability of the complexes has also been explored.Figure optionsDownload as PowerPoint slide