1,10-邻菲啰啉衍生物钌配合物的合成、 表征及与DNA和BSA的相互作用

通过2-(4-吡啶)-咪唑[4,5-f]-1,10-邻菲啰啉(L₁)与[Ru(η⁶-cymene)(μ-Cl)Cl]₂反应合成了3种新型芳基钌配合物, 并利用新配体2-(4-咪唑基苯基)咪唑[4,5-f]-1,10-邻菲啰啉(L₂)与RuCl₃反应合成了配合物4. 利用核磁共振波谱、 质谱等对配合物进行了表征. 通过紫外光谱和圆二色谱研究了配合物在缓冲溶液中的稳定性及与CT-DNA的相互作用, 利用荧光光谱研究了配合物与牛血清蛋白的作用, 用乌氏黏度计测试了配合物对DNA黏度的影响, 并通过荧光光谱、 凝胶电泳研究了配合物4在不同pH条件下的荧光响应及与pBR322 DNA的作用. 结果表明, 配合物通过嵌入的方式与DNA作用, 并对DNA的二级结构产生影响; 配合物1~4均可与牛血清蛋白的一个位点发生相互作用并使其发生静态荧光猝灭. 配合物4在光照条件下有活性氧生成, 可以使pBR322 DNA断裂并在酸性溶液中荧光增强.

Synthesis,Characterization and DNA,BSA Interactions of Mononuclear Ruthenium Complexes with Modified 1,10-Phenanthrolines Ligands†

Three novel arene-ruthenium complexes(1—3) were synthesized from 2-(4-pyridinyl)imidazo[4,5-f]-1,10-phenanthroline(L₁) and [(η⁶-cymene)Ru(μ-Cl)Cl]₂. A polypyridine-ruthenium complex(4) was synthesized from RuCl₃ and 2-(4-(1H-imidazol-1-yl)phenyl)-1H-imidazo[4,5-f]-1,10-phenanthroline(L₂). All the complexes were characterized by ¹H NMR, elemental analysis and ESI-MS. UV-Vis, circular dichroism and fluorescence techniques were used to study the interactions between complexes 1—4 and calf thymus DNA(CT-DNA) or BSA, respectively. Viscosity measurements were carried out to clarify further the interaction mode of complexes 1—4 with DNA. In addition, the interactions of complex 4 with pBR322 DNA were studied by gel electrophoresis, and the pH-related fluorescence spectra of complex 4 were recorded in various pH solutions. The results show that these complexes could interact with DNA via intercalation and disturbing the secondary structure of DNA. The static quenching for complexes 1—4 were observed when these complexes were titrated with BSA protein. Only one binding site was observed between these complexes and BSA and the binding constants were calculated. Under the UV light(365 nm), complex 4 could generate ¹O₂ and cleave pBR322-DNA efficiently and its fluorescencewere enhanced more than 56% when the solution pH was changed from 11.37 to 1.74.