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一种光酶,可以挑战乳酸基的循环
Bryce T Nicholls1, Tianzhang Qiao1, Todd K Hyster1
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, 14853 USA.
概括
一种新的光酶方法,使用了依赖于黄素的黄素.
科学领域:
- 有机合成 有机合成
- 生物催化剂是一种生物催化剂.
- 药品化学 药品化学 是一个
背景情况:
- 降解基循环对于合成复杂的有机分子至关重要.
- 通过胺基的激进循环合成N-异环基因,如乳糖,由于胺基的缓慢旋转,导致不必要的非循环产物,这是一项挑战.
- 现有的通过激素循环合成的乳合成方法往往具有较低的选择性.
研究的目的:
- 为了比较四种不同的方法合成alpha,beta,gamma和zeta-lactams使用激素循环.
- 确定选择性乳糖形成的最有效方法.
- 阐明最佳方法中提高选择性背后的机制.
主要方法:
- 针对乳糖合成的四种不同的还原基循环化策略的比较.
- 使用了光酶方法,采用了依赖于黄素的'-还原酶'.
- 分析了每个方法的产品选择性和产量.
主要成果:
- 与其他三种方法相比,光酶法显示出更高的产品选择性.
- 这种酶的方法有效地促进了所需乳酸产品的形成.
- 观察到的选择性归因于酶对cis amide异构体的优先结合.
结论:
- 使用依赖于黄素的'烯'-减少酶的光酶还原基循环化是一种高度选择性的合成多种乳酸的方法.
- 酶介导的基质预组织,特别是结合cis胺基异构体,是提高循环化效率和防止过早激素终结的关键.
- 这种方法在合成N-异环化合物方面取得了重大进展.
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