一个单核Ni(II) 脱胺胺复合体的glyoxalase I型半氧乙异构化反应活性
Katarzyna Rudzka1, Atta M Arif, Lisa M Berreau
1Department of Chemistry and Biochemistry, Utah State University, Logan, UT 84322-0300, USA.
Journal of the American Chemical Society
|December 21, 2006
概括
一种新型的 (II) 复合物催化半氧乙异型化,模仿大肠杆菌的glyoxalase I活性. 这种脱质胺复合物表现出选择性反应性,为生物金属离子催化提供了洞察力.
科学领域:
- 协调化学 协调化学
- 有机金属化学 有机金属化学
- 生物模拟催化剂的使用
背景情况:
- 半酸乙异构化是氧酶I酶活性的一个关键步骤.
- 了解合成类似物可以阐明生物机制.
- (II) 复合物是相关的,因为它们存在于金属酶中.
研究的目的:
- 合成和表征一个单核Ni(II) 脱质胺复合体.
- 为了研究这个复合物的半氧乙异构化反应性.
- 为了比较其与质子化模拟物和简单的Ni (II) 离子的反应性.
主要方法:
- 使用X射线晶体学,NMR,UV-vis,FTIR和元素分析合成和描述Ni(II) 复合物.
- 复合物的反应与一个半乙烯基 (PhC(O) CH(OH) SCD3) 在乙二中.
- 使用2H NMR光谱学监测反应.
- 使用质子化Ni (II) 复合体和NiBr2.2H2O. 的比较研究.
主要成果:
- 单核Ni(II) 脱胺复合物,[(bppppa-) Ni]ClO4.CH3OH (1),已成功合成和表征.
- 复合物1有效的异构化半氧乙到 (大约. 60% 的收益率).
- 阳离子联体对反应性至关重要,因为质子化模拟物是不反应的.
- 复合物1与产品没有反应,表明pKa差异很大.
结论:
- 无质子化Ni(II) 复合物是第一个表征合成模拟物,表现出与glyoxalase I相关的半酸乙异构化.
- 阳离子酸连接体对于促进半酸异构化至关重要.
- 这项研究提供了关于Ni (II) 促进的半氧乙异构的宝贵见解,区分了复杂与简单的离子催化.
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