作为一个关键步骤,使用不常见的7-endo Heck 循环作为关键步骤,对 guanacastepene N 的 enantioselective 总合成
Shin Iimura1, Larry E Overman, Ralph Paulini
1Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, 92697-2025, USA.
Journal of the American Chemical Society
|October 5, 2006
概括
研究人员使用一个关键的7-endo Heck循环化实现了 (+) - guanacastepene N 的第一个enantioselective总合成. 这一突破为复杂的瓜纳卡斯天然产品提供了新的途径.
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N是一种复杂的天然产品,具有潜在的生物活性.
- 以前的合成途径对瓜纳卡斯天然产品是有限的.
- 开发对抗选择性总合成对于访问和研究这些分子至关重要.
研究的目的:
- 开发 (+) - 瓜纳卡斯特N. 的一个融合的,enantioselective的总合成.
- 建立准备关键构建块的高效方法.
- 为了证明7个末端的Heck循环在构建复杂的分子架构中的实用性.
主要方法:
- 收合成策略. 收合成策略.
- 循环和循环烯碎片的酶选择性合成.
- 具有挑战性的结合加法形成一个四元立体中心.
- 区域选择性7-endo Heck 循环对于三环核形成.
主要成果:
- 成功开发了一种融合的,对 (+) - 瓜纳卡斯泰N.的酶选择性总合成.
- 能够有效地合成出纯质的 A 和 C 环碎片.
- 通过结合添加构建C11四等碳立体中心.
- 通过 7-endo Heck 循环形成三环中间体.
结论:
- 开发的合成途径代表了 (+) - 瓜纳卡斯特N的第一个总合成.
- 这项工作提供了瓜纳卡斯天然产品的第二次enantioselective总合成.
- 关键的7个末端的赫克循环是构建复杂的多环系统的强大工具.
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