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Enantioselective Total Synthesis of (-)-Verarine via Late-Stage Bond Ablation
Kyle J Cassaidy1, Viresh H Rawal1
1Department of Chemistry, University of Chicago, Chicago, Illinois60637, United States.
Abstract:
The selective cleavage of C-N bonds in complex molecules offers a powerful strategy for accessing new chemical space. Described herein is an enantioselective total synthesis of (-)-verarine that combines a highly efficient [2 + 2 + 2] cycloisomerization, which constructs three rings of the contiguous hexacyclic cevanine skeleton in a single operation, with a late-stage regioselective ablation of a benzylic C-N bond to unveil the veratramine framework. This precise reorganization of a densely functionalized Veratrum scaffold provides a concise total synthesis of (-)-verarine and should enable access to other members of this family.
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