Synthesis, DNA-binding and photocleavage studies of Ru(II) complexes of phenyl-(4,5,9,14-tetraaza-benzo[b]triphenylen-1,1-yl)-methanone

Journal of Chemical Sciences (Impact Factor: 1.19). 07/2009; 121(4):397-405. DOI: 10.1007/s12039-009-0046-3


A novel polypyridyl ligand phenyl-(4,5,9,14-tetraaza-benzo[b]triphenylen-1,1-yl)-methanone (PTBM) and its complexes [Ru(phen)2(PTBM)]2+ (1) (phen = 1,10-phenanthroline) and [Ru(bpy)2(PTBM)]2+ (2) (bpy = 2,2′-bipyridine) have been synthesized and characterized by elemental analysis, mass spectroscopy, and 1H NMR. The DNA-binding properties of the two complexes were investigated by spectroscopic and viscosity measurements. The
results indicate that both complexes bind to DNA via an intercalative mode and the DNA-binding affinity of complex 1 is greater than that of complex 2. When irradiated at 365 nm, complex 1 was found to be a more-effective DNA-cleaving agent than complex 2.

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