A short enantioselective synthesis of 6-substituted cis-2,8-dioxabicyclo[3.3.0]octan-3-ones is described. The pivotal step is coupling of a tertiary radical generated directly from a tertiary alcohol with a 3-chloro-5-alkoxybutenolide. This strategy is applied toward scalable 14–15 step syntheses of three rearranged spongian diterpenoids: cheloviolenes A and B and dendrillolide C.

中文翻译：

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6取代的顺式-2,8-二恶双环[3.3.0] octan-3-one的多功能构建：Cheloviolenes A和B和Dendrillolide C的短对映选择性全合成

描述了6-取代的顺式-2,8-二氧杂双环[3.3.0] octan-3-ones的短对映选择性合成。关键步骤是将由叔醇直接生成的叔自由基与3-氯-5-烷氧基丁烯内酯偶联。该策略适用于三种重排的海绵状二萜类化合物的可扩展的14-15步合成：螯合物A和B和树突状内酯C。