title: Enantioselective synthesis of the ABC ring motif of norzoanthamine based on asymmetric Robinson annulation reactions.
abstract: 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 Robinson annulation 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 of the natural product.
authors: Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093-0358, USA.
authors: Thong X
authors: TX
authors: Nguyen
authors: Marianna
authors: M
authors: Dakanali
authors: Lynnie
authors: L
authors: Trzoss
authors: Emmanuel A
authors: EA
authors: Theodorakis
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