通过Fe-only化酶活性位点的氨类型的二激活
Aaron K Justice1, Rachel C Linck, Thomas B Rauchfuss
1Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Avenue, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|October 14, 2004
概括
复合物与H2和HX基质发生光化学反应,形成二化物和相关物种. 这些发现为仅含铁的基酶与二和终端基联体提供了第一个模型.
科学领域:
- 有机金属化学 有机金属化学
- 摄影化学的使用.
- 生物仿真催化剂的使用
背景情况:
- 纯铁基酶是生物代谢的关键酶.
- 了解它们的活性位点需要合成模型来模拟关键连接体的安排.
- 复合体为探索二激活和相关的催化过程提供了一个平台.
研究的目的:
- 为了合成和描述新型的二化复合物.
- 在光化学条件下研究这些复合物与各种基质的反应性.
- 为纯铁化酶的活性位点建立新的合成模型.
主要方法:
- 照片化学反应涉及鲁复合物和H2或HX.
- 核磁共振 (NMR) 光谱用于结构阐明.
- 用X射线晶体学来确定精确的分子结构.
- 对H2-D2交换反应的催化研究.
主要成果:
- 在Ru2的光化学反应中{S2C3H6}{CO) 4{PCy3}2与H2产生二化物Ru2{S2C3H6}{mu-H}{H}{CO3}{PCy3}2.
- 将HX基质 (OTs,Cl,SPh) 摄影添加到复合物中,产生了相应的Ru2{\displaystyle Ru2{\displaystyle S2C3H6}{\displaystyle Ru2{\displaystyle S2}C3H6}{\displaystyle Ru2{\displaystyle S2}C3H6}{\displaystyle Ru2{\displaystyle Ru2}S2}C3H6}{\displaystyle Ru2{\displaystyle Ru2}S2}C3H6}{\displaystyle Ru2{\displaystyle Ru2{\displaystyle Ru2}S2}C3H6}{\displaystyle Ru2{\displaystyle Ru2}C3H6}{\displaystyle Ru2}{\displaystyle Ru2{\displaystyle Ru2}S2}{\displaystyle Ru2{\displaystyle Ru2}S2}{\displaystyle Ru2}
- 合成的鲁复合物,特别是[Ru2 ((S2C3H6) ((mu-H) ((CO) 3 ((PCy3) 2 ((H2)) ]+和[Ru2 ((S2C3H6) ((mu-H) ((CO) 3 ((PCy3) 2 ((HD) ]+,在H2-D2交换中表现出催化活性.
结论:
- 该研究成功合成和表征了作为铁纯化酶的第一个结构和功能模型的复合物.
- 这些模型具有二和终端基联体,对于酶活性至关重要.
- 在H2-D2交换中的催化活性突显了这些复合物的潜力,可以模仿酶的转换.
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