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Updated: May 16, 2026

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An enantioselective total synthesis of helioporins C and E
Wibke Lölsberg1, Susen Werle, Jörg-Martin Neudörfl
1Department of Chemistry, University of Cologne, Greinstrasse 4, 50939 Köln, Germany.
Abstract:
A short and enantioselective total synthesis of helioporins C and E, which are bioactive marine diterpenes containing a serrulatane or amphilectane skeleton, was elaborated. The chirogenic step, i.e. a Cu(I)-catalyzed allylic alkylation of a cinnamyl chloride with methylmagnesium bromide, proceeded with virtually complete enantioselectivity (99% ee) in the presence of a chiral phosphine-phosphite ligand. The other stereocenters were diastereoselectively established through Me(2)AlCl-mediated cationic cyclization and Ir-catalyzed hydrogenation.
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