新型多吡啶配体的设计及其对配合物与DNA作用机制的影响

近年来 ,以钌 ( )多吡啶配合物为探针研究 DNA的结构已成为生物无机化学领域中的一个热点1,2 ] .这些配合物由于热力学稳定性好 ,光化学和光物理信息丰富 ,在研究 DNA内部的电子转移和Fig.1　 Structures of the ligandsDNA的结构识别等方面均有重要的作用3～ 7] .在配合物与 DNA的相互作用中 ,配合物的形状、大小以及中心离子电荷等都有一定的影响8] ,其中 ,配合物的形状起着至关重要的作用 ,与 DNA的形状匹配的配合物与DNA的结合较强 .这些配合物中通常含有平面性较大的芳香环配体 ,可插入到 DNA的碱基对之间 ,并与 DNA具有…

Design of New Polypyridyl Ligands and Their Effects on DNA-binding Mechanisms of Complexes

Two structurally related polypyridyl ligands ODHIP(3,4-dihydroxyl-imidazophenanthroline), MDHIP(2,4-dihydroxyl-imidazo phenanthroline) and their ruthenium(II) complexes Ru(phen) 2ODHIP] 2+ and Ru(phen) 2MDHIP] 2+ were prepared and characterized. Their DNA-binding properties were studied by spectroscopic methods and viscosity measurements. The results indicated that the two complexes are bound to DNA by different modes due to the different planarities of ligands. For the complex Ru(phen) 2MDHIP] 2+, the 2- position ortho group of MDHIP could form an intramolecular hydrogen bond with the nitrogen atom of the imidazole ring to extend the planarity and strengthen the binding affinity. On the other hand, the 4- position ortho group hindered the complex from intercalating into the base pairs of DNA, and finally, making the complex bind to DNA by a partial intercalative mode. However, for the complex Ru(phen) 2ODHIP] 2+, there was no intramolecular hydrogen bond formed and the two ortho groups further increased the steric effect and decreased the binding affinity, thus making the complex bind to DNA by groove binding mode.