Bilobalide is a tetracyclic sesquiterpene containing three contiguous γ-lactone rings and an unusual tert-butyl group, which is found in the leaves of the ginkgo tree (Ginkgo biloba). Three different photochemical approaches towards bilobalide's unique skeleton are presented. A meta photocycloaddition, a [2 + 2] photocycloaddition, and a Paternò–Büchi-reaction were chosen as the respective key steps
白果内酯是含有三个连续γ内
酯环和一个不寻常的四环
倍半萜叔丁基,其在
银杏树(叶发现
银杏)。提出了三种不同的光
化学方法对
白果内酯独特的骨架。甲元光环,[2 + 2]光环,和一个的Paternò-步琪反应被选为相应关键步骤。