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Updated: Aug 6, 2026

Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine
Published on: February 16, 2018
Total Synthesis of the Diterpene Alkaloid Thelepogine through Enyne Hydroamination
Christoph Etling1, Matthew DiCairano2, Dirk H Trauner1
1Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States.
Abstract:
The total synthesis of the atypical diterpene alkaloid thelepogine is reported. Our pathway features the asymmetric construction of a carbotricyclic intermediate that undergoes a 2,3-Wittig-Still rearrangement of a tetrasubstituted allylic alcohol, installing two adjacent quaternary stereocenters. The α-tertiary amine of thelepogine was delineated from a quaternary carbon through a Beckmann-type rearrangement, while the unusual pyrrolizidine moiety was assembled through a copper(I)-catalyzed (4 + 1) cycloaddition of an amino enyne, amounting to a 2-fold hydroamination. Our synthesis enables the full spectroscopic characterization of thelepogine, which had previously been characterized only by single-crystal X-ray diffraction of a derivative, and opens the door to comprehensive biological evaluation.
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