Enantioselective Synthesis of the ABC Ring Motif of Norzoanthamine Based on Asymmetric Robinson Annulation Reactions
作者:Thong X. Nguyen、Marianna Dakanali、Lynnie Trzoss、Emmanuel A. Theodorakis
DOI:10.1021/ol200966z
日期:2011.7.1
An enantioselective strategy for the synthesis of tetracyclic motif 5, representing the northern fragment of norzoanthamine, is presented. Key to the strategy is the use of two asymmetric Robinsonannulation reactions that produce the tricyclic ABC ring system with excellent stereoselectivity. Further functionalization at the periphery of the C ring produces compound 5 containing six contiguous stereocenters