DNA Mismatch Recognition by a Hexacoordinate Silicon Sandwich–Ruthenium Hybrid Complex

The diastereoselective synthesis
of two dinuclear Ru–Si
complexes is reported, in which silicon­(IV) is coordinated in an octahedral
fashion by two 1,10-phenanthrolines and one 4,5-pyrenediolato ligand
and additionally η6-coordinated to a (η5-pentamethylcyclopentadienyl)­ruthenium­(II) moiety through
one fused benzene ring of the pyrene ligand. One of these Ru–Si
hybrid complexes was found to selectively stabilize DNA duplexes that
contain cytosine–cytosine or cytosine–thymine mismatches,
and it is proposed that this occurs by a novel dual insertion/intercalation
binding mode in which the entire ruthenium sandwich unit is introduced
into the DNA π-stacking at the site of the DNA mismatch.

本文报道了两种双核Ru-Si复合物的对映选择性合成，其中硅(IV)通过两个1,10-菲罗啉和一个4,5-芘二醇酸配体以八面体形式配位，并且通过芘配体的一个并合苯环额外η6-配位于(η5-五甲基环戊二烯基)钌(II)基团。研究发现，其中一种Ru-Si杂化复合物能够选择性地稳定含有胞嘧啶-胞嘧啶或胞嘧啶-胸腺嘧啶错配的DNA双链，并提出这种作用是通过一种新型的双重插入/嵌入结合模式实现的，其中整个钌 sandwich 单元被引入到DNA π-堆积在DNA错配位的点。