不对称的环素总合成
Junyang Liu1, Jianlei Wu1, Jian-Hong Fan1
1Department of Chemistry , Southern University of Science and Technology , Shenzhen 518055 , China.
Journal of the American Chemical Society
|April 5, 2018
概括
第一个异常的C25类固醇的全合成在18个步骤中完成. 一个关键的II型分子内 [5 + 2] 循环添加有效地构建了具有挑战性的bicyclo[4.4.1] A/B环系统.
科学领域:
- 有机化学
- 合成化学
- 自然产品合成
背景情况:
- 环醇是一种不寻常的C25类固醇,结构复杂.
- 复杂的自然产品的合成在有机化学中提出了重大挑战.
- 不对称的合成对于获得质纯化合物至关重要.
研究的目的:
- 为了实现第一个不对称的环素的总合成.
- 开发一种高效的合成路径来构建独特的bicyclo[4.4.1] A/B环系统.
- 探索复杂的类固醇结构的新合成方法.
主要方法:
- 使用了18个步骤的线性合成序列.
- 商用化合物11作为起始材料.
- 用于构建核心环系统的II型内分子 [5 + 2] 循环添加.
主要成果:
- 第一个不对称的环氨酸全合成成功完成.
- 具有挑战性的bicyclo[4.4.1] A/B环系统,具有紧张的抗Bredt双键,有效地构建.
- 循环添加反应具有很高的二元选择性.
结论:
- 开发的合成策略提供了有效的循环氨酸的途径.
- 该研究证明了II型分子内 [5 + 2] 循环添加在构建复杂的多环系统中的实用性.
- 这种合成为进一步研究环素及其类型的生物活性开辟了道路.
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