Synthesis of the fused tetrahydrofuran motif comprising the ABC rings of the marine ladder polyethers tamulamides A and B has been achieved via two different polyepoxide cascade strategies. Investigations into a triepoxide cascade under aqueous conditions revealed the importance of the electronic nature of the cascade end-group with this initial approach. Ultimately, a diepoxide cascade under basic conditions proved most successful, providing the ABC tetrahydropyran triad in 41% yield.

中文翻译：

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tamulamides A和B的ABC骨架的合成

经由两种不同的聚环氧化物级联策略已经实现了合成包含海洋梯形聚醚tamulamides A和B的ABC环的稠合四氢呋喃基序。在水性条件下对三环氧化物级联反应的研究揭示了这种初始方法对级联端基电子性质的重要性。最终，在碱性条件下的二环氧化物级联被证明是最成功的，以41％的产率提供了ABC四氢吡喃三联体。