SYNTHESIS, SPECTRAL STUDIES AND EVALUATION OF DNA BINDING, PHOTOCLEAVAGE, ANTICANCER ACTIVITY OF RU(II) POLYPYRIDYL COMPLEXES OF 2-(3,4,5-TRIMETHOXY-PHENYL)-H-IMIDAZOLE[4,5-F][1,10]PHENANTHROLINE

The two novel Ru(II) polypyridyl complexes of the type [Ru(NN)2L](ClO4)2.2H2O,where NN is dmp=4,4-dimethyl-1,10 ortho phenanthroline and dmb=4,4-dimethyl 2,2-bipyridine and L is Intercalator ligand, TMIP=2-(3,4,5-Trimethoxy-phenyl)-H-imidazole[4,5-f][1,10]phenanthroline were synthesized and characterized by different spectroscopic techniques. The binding ability of Ru (II) complexes with CT-DNA was investigated by Biophysical studies – UV-Visible absorption studies, Fluorescence studies (Emission & Quenching) and Viscosity studies. The binding constants of these complexes from absorption studies are 1.2x105 M-1and 8x104M-1respectively.These values are less as compared to the existing TMIP complex [Ru(phen)2TMPIP]+2, indicative of the effect of substitution over the ancillary ligand which reduce the binding capacity of metal complex to CT-DNA. The results from the viscosity studies suggest an intercalative binding mechanism. The DNA cleavage studies show that the Ru (II) complexes successfully cleaved the pBR322 DNA. Both the complexes exhibit not notable anti cancer acivity.