Operationally simple, stereocontrolled semisyntheses of the anticancer rotenoids elliptone and 12aβ-hydroxyelliptone, isolated from Derris elliptica and Derris trifoliata, respectively, are described. Inspired by the work of Singhal, elliptone was prepared from rotenone via a dihydroxylation-oxidative cleavage, chemoselective Baeyer–Villiger oxidation, and acid-catalyzed elimination sequence. Elaboration of elliptone to 12aβ-hydroxyelliptone was achieved via a diastereoselective chromium-mediated Étard-like hydroxylation. The semisynthesis of elliptone constitutes an improvement over previous methods in terms of safety, scalability, and yield, while the first synthesis of 12aβ-hydroxyelliptone is also described.

中文翻译：

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立体控制的椭圆和12aβ-羟基磷脂半合成

操作简单，立体控制抗癌鱼藤酮类鱼藤和12aβ-hydroxyelliptone，从分离的semisyntheses鱼藤elliptica和鱼藤，分别进行说明。受辛格（Singhal）的启发，通过二羟化-氧化裂解，化学选择性的拜耳-维利格（Baeyer-Villiger）氧化和酸催化的消除顺序，从鱼藤酮制得了椭圆酮。通过非对映选择性铬介导的类似埃塔德的羟基化作用，将椭圆烷修饰为12aβ-羟基椭圆烷。椭圆的半合成在安全性，可扩展性和产率方面构成了对先前方法的改进，同时还描述了12aβ-羟基椭圆的首次合成。