倍半萜chloranthalactone A和F的全合成

Total Synthesis of Sesquiterpenoid Chloranthalactone A and F

采用仿生生源合成策略,金粟兰内酯(+)-chloranthalactone F被首次合成。探索了如何构建(+)-chloranthalactone F的生源前体3/5/6三环不饱和内酯(+)-chloranthalactone A。从(R)-Hajos-Wiechert酮出发,选择性合成了热力学不稳定的反式氢化茚酮,经Wharton转化和Simmons-Smith环丙烷化等关键步骤,制备了3/5/6三环不饱和内酯(+)-chloranthalactone A,最终经[2+2]仿生途经完成了首次(+)-chloranthalactone F全合成。该工作揭示了(+)-chloranthalactone F的生源合成途径以及确定其绝对构型。

Total synthesis of（＋）-chloranthalactone F was first been accomplished via biomimetic synthetic strategies. Firstly, the synthetic strategies to the unsaturated lactones and the construction of the 3/5/6 tricyclic framework were probed into the biomimetic monomer named（＋）-chloranthalactone A. Starting from the prepared（R）-Hajos-Wiechert ketone, a trans-fused, thermodynamically unstable hydrindanone was synthesized and further exploration ensured the asymmetric synthesis of congested 3/5/6 core skeleton by way of Wharton transposition and Simmons-Smith reaction. Subsequently, the syntheses of unsaturated lactones were accomplished basing on the strategies of ketone transposition and [2＋2] electro-cyclization/ring-opening/lactonization. This work has revealed biogenesis pathway of（＋）-chloranthalactone F and to determine its absolute configuration.