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Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
在非对称循环化中的立体化学多样性,通过记忆性
Takeo Kawabata1, Seiji Matsuda, Shimpei Kawakami
1Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan. kawabata@sci.kyoto-u.ac.jp
Journal of the American Chemical Society
|November 30, 2006
概括
这项研究提出了一种enantiodivergent循环化方法,用于合成奇拉循环氨基酸. 反应条件控制了配置是否保留或逆转,产生高纯度的两个反体.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
- 药用化学 医学化学
背景情况:
- 性循环氨基酸是药物发现和科学中宝贵的组成部分.
- 开发有效的方法来获取多种奇拉循环氨基酸,特别是具有具有挑战性的立体中心的氨基酸,仍然是合成化学的一个关键目标.
研究的目的:
- 开发一种对N-Boc-N-omega-bromoalkyl-alpha-amino acid衍生物进行enantiodivergent不对称循环的策略.
- 在循环化过程中控制立体化学结果 (保持或反转配置).
- 用四位置换的立体中心合成基纯循环氨基酸,并探索螺旋循环化和合加法反应中的应用.
主要方法:
- 在N-Boc-N-omega-bromoalkyl-alpha-amino酸衍生物的不对称循环.
- 使用不同的基和溶剂系统 (DMF中的胺为保留,THF中的胺为反转).
- 在整个反应序列中保持原始氨基酸性.
主要成果:
- 成功合成阿扎环性氨基酸的反转基因分离,具有高反转基因过剩 (高达98% ee).
- 立体化学控制的演示:保留与胺基的配置和胺基的反转.
- 适用于螺旋循环和分子内合物添加,产生达亚斯胺化合物和四化诺衍生物,高达99%的EE.
结论:
- 已经建立了一种用于合成循环氨基酸的两种酶体和从易于获得的L-α-氨基酸中置换的立体中心的多功能协议.
- 开发的方法提供了对立体化学的精确控制,使得可以访问多种类型的性支架.
- 该协议适应螺旋循环化和并联加的适应性扩大了其在合成复杂的性分子中的实用性.
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