Synthesis, characterization and DNA-binding studies of chiral ruthenium(II) complexes with 2-(5-nitrofuran-2-yl)-1H-imidazo[4,5-f][1,10]phenanthroline

Two new chiral ruthenium(II) complexes Delta-[Ru(bpy)(2)(nfip)](2+) and Lambda-[Ru(bpy)(2)(nfip)](2+) (in which bpy=2,2'-bipyridine, nfip=2-(5-nitrofuran-2-yl)-1H-imidazo[4,5-f][1,10]phenanthroline) have been synthesized and characterized by elemental analysis, ES-MS, H-1 NMR and CD spectra. The binding properties of two chiral complexes with calf thymus DNA have been investigated by different spectrophotometric methods and viscosity measurements. A subtle but detectable difference was observed in the interaction of both enantiomer with CT-DNA, Delta enantionner binds with DNA more strongly than Lambda enantiomer. Viscosity experiments provided evidence that both Delta-[Ru(bpy)(2)(nfip)](2+) and Lambda-[Ru(bpy)(2)(nfip)](2+) bound to DNA by intercalation. (c) 2009 Elsevier B.V. All rights reserved.