Preparation of a functionalized tetracyclic intermediate for the synthesis of rhodexin A.
نویسندگان
چکیده
An efficient synthesis of the tetracyclic steroid core, 19, of rhodexin A and sarmentogenin is reported. An initial inverse-electron-demand Diels-Alder reaction of the acyldiene 6 with the silyl enol ether 7a gave the cycloadduct 8 with the required four contiguous stereocenters in a single step. This compound was then transformed into the methylated enedione 13 which afforded after a reductive alkylation and annulation sequence the tetracycle 19.
منابع مشابه
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ورودعنوان ژورنال:
- Organic letters
دوره 10 16 شماره
صفحات -
تاریخ انتشار 2008