Experimental and Density-Functional-Theory (DFT) Studies on the DNA-Binding Trend and Spectral Properties of the Ruthenium Complexes [Ru(4,7-dmp)(bdip)]2+ and [Ru(bpy)2(bdip)]2+ (4,7-dmp=4,7-Dimethyl-1,10-phenanthroline, bdip=2-(1,3-Benzodioxol-4-yl)-1H-imidazo[4,5-f] [1,10]phenanthroline, bpy=2,2′-bipyridine)

✍ Scribed by Li-Feng Tan; Sheng Zhang; Hui Chao; Kang-Cheng Zheng; Fang Wang; Yue Xiao; Liang-Nian Ji

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: German
• Weight: 320 KB
• Volume: 90
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.200790188

✦ Synopsis

Abstract

The new ligand bdip (=2‐(1,3‐benzodioxol‐4‐yl)‐1__H__‐imidazo[4,5‐f][1,10]phenanthroline) and its Ru^II^ complexes [Ru(4,7‐dmp)~2~(bdip)]^2+^ (1; 4,7‐dmp=4,7‐dimethyl‐1,10‐phenanthroline) and [Ru(bpy)~2~(bdip)]^2+^ (2; bpy=2,2′‐bipyridine) were synthesized and characterized by elemental analysis, MS, ^1^H‐NMR, and cyclic voltammetry. The DNA‐binding properties of 1 and 2 to calf‐thymus DNA (CT‐DNA) were investigated by different spectrophotometric methods and viscosity measurements as well as by equilibrium dialysis and circular‐dichroism (CD) spectroscopy. The results suggest that both complexes bind to DNA through intercalation, and that the ancillary ligands of (polypyridine)ruthenium(II) complexes have significant effects on the spectral properties and DNA‐binding behavior of the complexes. Theoretical studies for these complexes were also carried out by the density‐functional‐theory (DFT) method. The trend in the DNA‐binding affinity and some electrochemical and spectral properties of the complexes were confirmed by the DFT calculations.