Herein, we present a novel approach to construct the A-B-C-D ring system of anislactone-type sesquiterpenoids. This innovative strategy involves a H₂O₂-mediated oxidative ring contraction reaction to form a 5/5 fused skeleton, while simultaneously generating contiguous quaternary carbon centers (CQCCs). Additionally, γ-lactones (A- and D-rings) are assembled through Pummerer reaction initiated cyclization and sequential Mukaiyama hydration/translactonization, respectively. Despite our efforts to introduce a hydroxyl group at C7 via C–H oxidation, these endeavors ultimately proved unsuccessful.

中文翻译：

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茴香内酯型倍半萜四环骨架的新方法


在此，我们提出了一种构建茴香内酯型倍半萜类化合物 A-B-C-D 环系统的新方法。这种创新策略涉及 H ₂ O ₂ 介导的氧化环收缩反应，形成 5/5 融合骨架，同时生成连续的季碳中心 (CQCC)。此外，γ-内酯（A-环和D-环）分别通过Pummerer反应引发的环化和连续的Mukaiyama水合/反内酯化来组装。尽管我们努力通过 C-H 氧化在 C7 上引入羟基，但这些努力最终被证明是不成功的。