Abstract A cascade dienyne ring-closing metathesis approach has been applied to the synthesis of the tetracyclic carbon framework of a new class of hybrid compounds—the taxosteroids—possessing carbon frameworks incorporating moieties characteristic of both taxanes (such as AB rings) and steroids (ie, CD system and side chain). This tandem cyclization is highly stereoselective, allowing the one-step formation of the bicyclo [5.3. 1] ...
