Series of Structural and Functional Models for the ES (Enzyme–Substrate) Complex of the Co(II)-Containing Quercetin 2,3-Dioxygenase
作者:Ying-Ji Sun、Qian-Qian Huang、Jian-Jun Zhang
DOI:10.1021/ic402695c
日期:2014.3.17
CoII–flavonolate complexes [CoIILR(fla)] (LRH = 2-[bis(pyridin-2-ylmethyl)amino]methyl}-p/m-R-benzoic acid; R = p-OMe (1), p-Me (2), m-Br (4), and m-NO2 (5); fla = flavonolate) were designed and synthesized as structural and functional models for the ES (enzyme–substrate) complexes to mimic the active site of the Co(II)-containing quercetin 2,3-dioxygenase (Co–2,3-QD). The metal center Co(II) ion in each complex
一系列的单核的Co II -flavonolate络合物[CO II大号- [R(FLA)](大号ř ħ = 2 - [双(吡啶-2-基甲基)氨基]甲基} - p /米-R -苯甲酸; R = p -OMe(1),p -Me(2),m -Br(4)和m -NO 2(5); fla =黄酮酸酯)被设计并合成为ES(酶-底物)复合物的结构和功能模型,以模拟含Co(II)的槲皮素2,3-二加氧酶(Co-2,3-QD)的活性位点。每个络合物中的金属中心Co(II)离子显示出相似的扭曲八面体几何形状。模型复合物在低温下显示出高的酶型双加氧反应性(配位底物黄酮酸酯的氧化O-杂环开环),这可能是由于配体中的羧酸酯基团所致。反应性表现出依赖于取代基的顺序-OMe(1)> -Me(2)> -H(3)14b> -Br(4)> -NO 2(5),而Hammett图是线性的(ρ= −0.78)。这可以解释为配体