Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.
Angew Chem Int Ed Engl. 2020 Apr 20;59(17):6894-6901. doi: 10.1002/anie.201916613. Epub 2020 Mar 9.
Presented here is a concise synthesis of secu'amamine A, and fluvirosaones A and B from readily available allosecurinine and viroallosecurinine. The key C2-enamine derivative of (viro)allosecurinine, the presumed biosynthetic precursors of these natural products, was accessed, for the first time, by a VO(acac) -mediated regioselective Polonovski reaction. Formal hydration and 1,2-amine shift of this pluripotent enamine compound afforded secu'amamine A. Formal oxidative [3+2] cycloaddition reaction between this enamine and TMS-substituted methallyl iodide reagent paved the way to the precursors of fluvirosaones A and B. The relative stereochemistry at the C2 position of these advanced intermediates governs the fate of 1,2-amine shift leading to fluvirosaones A and B. The syntheses of potential biosynthetic precursors and investigations of their chemical reactivities have provided insights regarding the biogenesis of these natural products.
本文简要综述了 secu'amamine A、fluvirosaones A 和 B 的全合成。这些天然产物的生物合成前体，易得的 allo-菊粉奎宁碱和 viro-菊粉奎宁碱，通过 VO(acac)介导的区域选择性 Polonovski 反应首次得到了关键的 C2-烯胺衍生物。该多功能烯胺化合物通过形式水合和 1,2-胺移位，得到了 secu'amamine A。该烯胺与 TMS 取代的烯丙基碘试剂之间的形式氧化 [3+2] 环加成反应为 fluvirosaones A 和 B 的前体铺平了道路。这些高级中间体 C2 位的相对立体化学决定了 1,2-胺移位的命运，从而得到 fluvirosaones A 和 B。潜在生物合成前体的合成及其化学反应性的研究为这些天然产物的生物合成提供了线索。
