State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China.
Angew Chem Int Ed Engl. 2019 May 13;58(20):6659-6662. doi: 10.1002/anie.201902043. Epub 2019 Apr 4.
The concise total syntheses of (-)-indoxamycins A and B is reported. The chemistry features a seven-step preparation of a highly congested [5.5.6] tricyclic advanced common intermediate from a readily available R-carvone derivative. Key steps involve a Pauson-Khand reaction for the rapid construction of a basic scaffold bearing a quaternary carbon, a copper-catalyzed Michael addition for the introduction of another adjacent all-carbon quaternary stereocenter, and a tandem retro-oxa-Michael addition/1,2-addition/oxa-Michael addition for the installation of a trisubstituted olefin side chain. This synthetic strategy allows for easy access to both enantiomers of this family of natural products and their analogues from cost-effective starting material through straightforward chemical transformations.
报告了 (-)-indoxamycin A 和 B 的简洁全合成。该化学合成的特点是从易得的 R-carvone 衍生物出发，经过七步反应制备高度拥挤的 [5.5.6] 三环桥环高级中间体。关键步骤包括 Pauson-Khand 反应，快速构建带有季碳原子的基本骨架，铜催化的 Michael 加成反应引入另一个相邻的全碳季碳中心，以及串联的反式-氧杂-Michael 加成/1,2-加成/氧杂-Michael 加成反应，用于安装三取代烯烃侧链。这种合成策略允许通过简单的化学转化，从具有成本效益的起始原料轻松获得这一系列天然产物及其类似物的两种对映异构体。
