木藜芦烷二萜在结构上的新颖性和多样性为合成化学家提供了发展新反应和新策略的广阔平台。本项目拟采用汇聚式的合成策略用于两类木藜芦烷二萜的高效不对称合成。研究内容包括：以去芳香化诱导的[5+2]环加成/频哪醇重排串联反应为关键步骤，实现双环[3.2.1]辛烷结构的快速构建，同时，利用2,2-二甲基-1,3-环戊二酮经还原去对称化构建另一偶联片段。二者通过Mukaiyama aldol反应和pinacol coupling反应进行组装，高效构建出grayanane型木藜芦烷二萜的5/7/6/5四环核心骨架。在此基础上，利用Wagner-Meerwein重排反应，构建出kalmane型二萜的5/8/5/5四环骨架。再分别通过两类骨架的后期官能团转化，实现多个代表性天然产物的集群式合成，从而发展一条木藜芦烷二萜的普适性合成策略。

Owing to their various unprecedented skeletons, complex structures and diverse bioactivities, grayanane diterpenoids have rendered them a great platform to develop new synthetic strategies and new reactions. In this proposal, we aim to develop a convergent strategy for the efficient asymmetric syntheses of two kinds of grayanane diterpenoids from readily accessible starting material. The major research plan include: 1) the application of oxidative dearomatization-induced (ODI) [5+2] cycloaddition/pinacol rearrangement cascade as key steps to build up the bicyclo[3.2.1]octane skeleton of grayanane diterpenoids, as well as the reductive desymmetrisation of 2,2-dimethylcyclopentane-1,3-dione to construct the other fragment; 2) with both of the two fragments in hand, assemblying them through the combination of Mukaiyama aldol and pinacol coupling reaction to access the 5/7/6/5 core structure possessing in grayanane-type diterpenoids; 3) transforming the aforementioned tetracyclic skeleton into the 5/8/5/5 core structure existing in kalmane-type diterpenoids utilizing Wagner-Meerwein rearrangement; 4) achieving the collective total syntheses of these two kinds of grayanoids by further cyclization or late-stage funcitionality elaboration. The current program showcases the versatility of convergent strategy employed in the highly efficient total syntheses of grayanane diterpenoids.