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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
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伊米因还原酶的计算设计:机制引导的立体选择性逆转和接口稳定
Kai Wu1, Jinrong Yan2,3, Qinde Liu1,4
1School of Pharmacy, Shanghai University of Medicine & Health Sciences 279 Zhouzhu Highway, Pudong New Area Shanghai 201318 China shaolei00@gmail.com.
Chemical science
|January 26, 2024
概括
研究人员设计了imine还原酶 (IREDs) 以实现精确的性胺合成. 计算设计在关键的药物中间体中实现了反向立体选择性和增强的稳定性.
科学领域:
- 生物催化和酶工程 生物催化和酶工程
- 不对称的合成方法
- 计算化学计算化学
背景情况:
- 胺基还原酶 (IRED) 是生产性氨基的重要生物催化剂.
- 了解IRED立体控制机制对于设计反选择性酶至关重要.
- 目前的局限性阻碍了针对特定氨基反体的向合成.
研究的目的:
- 为了研究imine降解酶的立体选择性催化机制.
- 设计具有定制立体选择性和改进性质的新型IRED变体.
- 探索计算设计在酶工程中的应用,用于制药合成.
主要方法:
- 通过使用2 - 基替代烯酸盐,研究了Paenibacillus mucilaginosus (PmIR) 的 (R) - 选择性IRED的立体选择机制.
- 采用计算设计来阐明静电相互作用在立体控制和反向选择性中的作用.
- 利用计算工具来识别稳定突变,以提高酶活性和热稳定性.
主要成果:
- 一种变体 (PmIR-Re) 实现了完全逆转的立体选择性到 (S) 选择性,具有>96%的反体过量 (ee).
- 另一种变体 (PmIR-6P) 的活性增加了5倍,化温度提高了12°C.
- 在400mM下,pmIR-6P成功地产生了 (R)-2-(2,5-difluorophenyl) -pyrrolidine,具有>99% ee.
结论:
- 在imine降解酶中阐明了控制立体控制的关键元素.
- 证明了计算设计的有效性,以实现特定的酶选择性和增强的酶稳定性.
- 强调了工程IREDs在有效合成制药中间体方面的潜力.
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