摘要
利用紫外吸收和荧光光谱法研究了不同钌(Ⅱ)配合物[Ru(bpy)2MDHIP]2+(MDHIP=2,4-二羟基-咪唑并[4,5-f]][1,10]邻菲咯啉)和[Ru(bpy)2ODHIP]2+(ODHIP=3,4-二羟基-咪唑并[4,5-f]][1,10]邻菲咯啉)与DNA的作用机制,并研究了这两个配合物与Cu2+的配位情况及配位形成双核配合物后的荧光性质变化.结果表明取代基的位置对配合物与DNA的作用机制及荧光性质等都具有较大影响.配体MDHIP上的2-位OH可以与相邻咪唑环上的N原子形成分子内氢键,增强配合物与DNA的插入作用.但其4-位OH取代基又会产生一定的位阻,使配合物只能以部分插入模式与DNA作用.而配体ODHIP上3-和4-位的两个OH取代基不能与相邻咪唑环上的N原子形成分子内氢键,并会产生更大的空间位阻,使得配合物不能插入到DNA的碱基对中.但ODHIP上的2个OH可以同时与Cu2+配位形成双核配合物,使配合物与DNA的作用模式由沟面结合改为插入结合,配合物的荧光减弱.
The DNA-binding and luminescent properties of [Ru（bpy）2MDHIP]2＋ and [Ru（bpy）2ODHIP]2＋（ODHIP=3,4-dihydroxyl-imidazophenanthroline,MDHIP= 2,4-dihydroxyl-imidazo phenanthroline） with the same substitutes on the different positions have been studied using spectra methods.The results indicated that the substitutes positions took effects on the binding modes of complexes to DNA.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 of [Ru（bpy）2MDHIP]2＋ to DNA,while the 4-position ortho group hindered the complex from intercalating fully into the base pairs of DNA,and finally,making the complex bind to DNA by a partial intercalative mode.For the ODHIP ligand,there was no intramolecular hydrogen bond formed and the two ortho groups further increased the steric effects and decreased the binding affinity,thus making [Ru（bpy）2ODHIP]2＋ bind to DNA by groove binding mode.Furthermore,the two ortho groups on ODHIP could coordinate with Cu2＋ to form the heterobimetallic complex [Ru（bpy）2（ODHIP）Cu]4＋,and the luminescence intensity decreased.
出处
《河南师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2012年第5期86-89,共4页
Journal of Henan Normal University(Natural Science Edition)
基金
国家自然科学基金(20601019
21004040)
深圳市基础研究计划重点项目(JC201005250058A)
关键词
钌配合物
DNA
取代基
插入结合
荧光
ruthenium complexes； DNA； substitute； intercalation； luminescence
