瓜纳卡斯提A和E的融合性,选性合成,具有选择性循环butan碎片化的特点
William D Shipe1, Erik J Sorensen
1Frick Chemical Laboratory, Princeton University, Princeton, NJ 08544-1009, USA.
Journal of the American Chemical Society
|May 25, 2006
概括
研究人员开发了一种合成瓜纳卡斯特的融合策略,使天然和非天然化合物的高效,反选择性生产成为可能. 关键步骤包括静态合,光环添加和降解碎片化,以形成立体中心和环形.
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:
- 瓜纳卡斯特是具有显著生物活性的复杂天然产品.
- 有效和酶选择性合成途径对于研究这些化合物及其类型至关重要.
研究的目的:
- 开发一个对 guanacastepene E. 的 enantioselective 合成的融合策略.
- 为了实现瓜纳卡斯烯A酶体的正式总合成.
- 建立构建复杂多环核和四元立体中心的方法.
主要方法:
- 收合成策略. 收合成策略.
- Pi-allyl Stille交叉合反应将关键中间体结合在一起.
- 内分子烯烯 [2+2] 光环添加.
- 用立体电子控制的循环布基的降解碎片.
- 通过环收缩从R-(-) - - 卡中合成乙烯基斯坦.
主要成果:
- 有效的,对 (+) - 和 (-) - 瓜纳卡斯特E.E.的选择性合成.
- (+) - 和 (-) - 瓜纳卡斯烯A的正式总合成.
- 成功建造了C-11四级立体中心.
- 瓜纳卡斯特骨架的中央七个成员环的形成.
- 从易于获得的性池起始材料开发一种新的途径,以实现功能化的乙烯基.
结论:
- 开发的融合策略对于构建瓜纳卡斯特核是非常有效的.
- 关键转换允许精确控制立体化学和环形形成.
- 这项工作为瓜纳卡斯特和相关复杂分子提供了有价值的合成路径.
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