School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
Org Lett. 2013 Mar 15;15(6):1298-301. doi: 10.1021/ol400228v. Epub 2013 Feb 28.
A concise total synthesis of spirocurcasone was accomplished. Key features of the synthesis involved a vinylogous Mukaiyama aldol reaction, a Carroll rearrangement of β-keto allyl ester derivative, an intramolecular aldol condensation, and a spiro ring formation by ring-closing metathesis of the pentaene compound. This synthetic work was complete in nine steps from (S)- or (R)-perillaldehyde without the use of protecting groups. Interestingly, the optical rotation of the synthetic spirocurcasone was different from the reported value of the natural product.
完成了螺环考卡酮的简洁全合成。该合成的关键特点包括：烯醇式 Mukaiyama 缩合反应、β-酮烯丙酯衍生物的 Carroll 重排、分子内Aldol 缩合以及五烯化合物的闭环复分解反应形成螺环。该合成工作从（S）-或（R）-紫苏醛开始，共九步，无需使用保护基团。有趣的是，合成螺环考卡酮的旋光度与天然产物的报道值不同。
