外选择性分子内 (4+3) 循环添加转化化Perhydroazulenes:一个非对称的形式合成的 (-) - 伪酸B
Zengsheng Yin1,2, Yuxuan He1, Guo Wei1
1Department of Chemistry, and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China.
Angewandte Chemie (International ed. in English)
|August 5, 2025
概括
研究人员开发了一种新的非对称合成伪酸B (PAB). 这种方法使用了一种新型的环氧乙基内分子循环添加来有效地构建PAB核心,包括一个具有挑战性的四级立体中心.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
- 自然产品的合成自然产品的合成
背景情况:
- 伪酸B (PAB) 是一种天然产品,具有已证明的抗瘤特性.
- 像PAB这样复杂的自然产品的高效和立体选择性合成对于进一步的生物研究和潜在的治疗开发至关重要.
研究的目的:
- 提出一种新的非对称的伪酸B (PAB) 正式总合成方法.
- 引入和探索一个新的类型的环氧乙烯基基质,用于分子内 (4+3) 循环添加反应.
- 为了实现PAB迄今为止最短的不对称合成.
主要方法:
- 不对称合成使用环氧乙基质的分子内 (4+3) 循环添加.
- 在 furan 上使用双相替代环氧化物来控制立体化学.
- 使用密度函数理论 (DFT) 计算来阐明反应机制和选择性.
- 结合一个的序列来简化合成过程.
主要成果:
- 成功合成了PAB的Trost合成中的一个关键中间体.
- 在分子内 (4+3) 循环加法中,产生了具有四等立体中心的转融化酸核.
- 该反应显示出高立体选择性,超过了以前的方法.
- DFT的计算证实了双晶在控制过渡状态的合性和外选择性方面的作用.
结论:
- 开发的非对称合成代表了PAB生产的重大进步.
- 新型环氧乙基环添加是一种强大的工具,用于构建复杂的多环结构.
- 这项工作提供了最短的抗瘤天然产品PAB的不对称合成.
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