七丁和7-脱氧七丁的总合成
Shupeng Zhou1, Rui Guo1, Peng Yang1
1State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis , Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China.
Journal of the American Chemical Society
|June 7, 2018
概括
这项研究首次对复杂的C20-diterpenoid化物septedine及其类似物进行了不对称的总合成. 关键步骤包括对抗选择性聚烯循环和不寻常的迪尔斯-阿尔德反应.
科学领域:
- 有机化学
- 整体综合
- 自然产品化学
背景情况:
- 塞普丁是一种复杂的C20-diterpenoid化物,具有独特的氧化七环基架.
- 由于septedine的复杂结构,它在合成方面面临着重大挑战.
研究的目的:
- 实现第一个不对称的septedine总合成 (2).
- 合成七度胺的7脱氧类似物 (3).
主要方法:
- 卡雷拉聚烯循环化为纯三环中间体.
- 双循环[2.2.2]八度核结构的离子迪尔斯-阿尔德反应.
- 催化醇异构化用于α-甲基安装.
- 桑福德Csp3-H氧化用于二次基的引入.
- 减少氨基化和N,O-化以最终组装氧化.
主要成果:
- 顺利的非对称总合成septedine (2) 和它的7-deoxy模拟物 (3).
- 展示关键的合成转化,包括聚烯循环,迪尔斯-阿尔德反应和C-H氧化.
- 具有高立体化学控制的复杂七环架构.
结论:
- 开发的合成途径提供了septedine及其类似物.
- 这项工作展示了构建复杂自然产品架构的创新策略.
- 该方法可用于合成相关的二类化物.
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