Liu J G, Ye B H, Zhang Q L, Zou X H, Zhen Q X, Tian X, Ji L N
Department of Chemistry, Zhongshan University, Guangzhou, PR China.
J Biol Inorg Chem. 2000 Feb;5(1):119-28. doi: 10.1007/s007750050015.
A series of enantiomerically pure polypyridyl ruthenium(II) complexes, delta- and lambda-Ru(bpy)2 (HPIP)2 (delta-1 and lambda-1; bpy=2,2'-bipyridine, HPIP = 2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline), delta and lambda-Ru(bpy)2(HNAIP)2 (delta-2 and lambda-2; HNAIP = 2-(2-hydroxy-1-naphthyl)imidazo[4,5-f][1,10]phenanthroline), delta- and lambda-Ru(bpy)2 (HNOIP)2 (delta-3 and lambda-3; HNOIP = 2-(2-hydroxy-5-nitrophenyl)imidazo[4,5-f][1,10]phenanthroline), and delta- and lambda-Ru(bpy)2(DPPZ)2 (delta-4 and lambda-4; DPPZ= dipyridophenazine), have been synthesized. Binding behavior of these chiral complexes to calf thymus DNA (CT-DNA) has been investigated by electronic absorption, steady-state emission, and circular dichroism spectroscopies, as well as by viscosity measurements and equilibrium dialysis binding studies. Several points came from the results. (1) The DNA-binding properties were distinctly different for the [Ru(bpy)2L]2+ (L=HPIP, HNAIP, HNOIP) series of ruthenium(II) complexes, which indicates that the photophysical behavior of the complexes on binding to DNA can be modulated through ligand design. (2) Different binding rates of individual enantiomers of complexes 1 and 4 to DNA were observed through dialysis experiments. The lambda enantiomer bound more rapidly than the lambda enantiomer and their different intercalative binding geometries were suggested to be responsible. (3) Both delta-2 and lambda-2 bound weakly to CT-DNA; delta-2 may bind through a partial intercalation mode, whereas lambda-2 may bind in the DNA groove. (4) There was no noticeable enantioselectivity for complexes 1, 3, and 4 on binding to CT-DNA. Both of their enantiomers can intercalate into DNA base pairs. It is noted that delta-3 and lambda-3 exhibited almost identical spectral changes on addition of CT-DNA, and a similar binding manner of the isomers to the double helix was proposed.
已经合成了一系列对映体纯的聚吡啶钌（II）配合物，即δ-和λ-Ru(bpy)2 (HPIP)2（δ-1和λ-1；bpy = 2,2'-联吡啶，HPIP = 2-(2-羟基苯基)咪唑并[4,5-f][1,10]菲咯啉）、δ-和λ-Ru(bpy)2(HNAIP)2（δ-2和λ-2；HNAIP = 2-(2-羟基-1-萘基)咪唑并[4,5-f][1,10]菲咯啉）、δ-和λ-Ru(bpy)2 (HNOIP)2（δ-3和λ-3；HNOIP = 2-(2-羟基-5-硝基苯基)咪唑并[4,5-f][1,10]菲咯啉）以及δ-和λ-Ru(bpy)2(DPPZ)2（δ-4和λ-4；DPPZ = 二吡啶并菲嗪）。通过电子吸收光谱、稳态发射光谱、圆二色光谱，以及粘度测量和平衡透析结合研究，对这些手性配合物与小牛胸腺DNA（CT-DNA）的结合行为进行了研究。结果得出了几点结论。（1）[Ru(bpy)2L]2+（L = HPIP、HNAIP、HNOIP）系列钌（II）配合物的DNA结合特性明显不同，这表明通过配体设计可以调节配合物与DNA结合时的光物理行为。（2）通过透析实验观察到配合物1和4的各个对映体与DNA的结合速率不同。λ对映体的结合比δ对映体更快，推测它们不同的插入结合几何结构是原因所在。（3）δ-2和λ-2与CT-DNA的结合都很弱；δ-2可能通过部分插入模式结合，而λ-2可能在DNA沟槽中结合。（4）配合物1、3和4与CT-DNA结合时没有明显的对映选择性。它们的两种对映体都可以插入DNA碱基对中。值得注意的是，加入CT-DNA后，δ-3和λ-3表现出几乎相同的光谱变化，并提出了异构体与双螺旋类似的结合方式。
