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A Divergent Polyene Cyclization for the Total Synthesis of Greenwayodendrines, Greenwaylactams, Polysin and Polyveoline.

ABSTRACT: We present a concise asymmetric total synthesis (5-8 steps) of nine sesquiterpenoid alkaloids featuring four different tetra-/pentacyclic scaffolds. To this end, a novel, bioinspired indole N-terminated cationic tricyclization has been developed, enabling the divergent synthesis of greenwayodendrines and polysin. Subtle variation of the C2-substituted indole cyclization precursor allowed switching between indole N- and C-termination. For the latter, a subsequent Witkop oxidation enabled conversion of the cyclopentene-fused indole into the eight-membered benzolactam to directly furnish the family of greenwaylactams. In addition, a diastereomeric C-termination product has been elaborated to provide access to polyveoline.

SUBMITTER: Plangger I

PROVIDER: S-EPMC7614870 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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A Divergent Polyene Cyclization for the Total Synthesis of Greenwayodendrines, Greenwaylactams, Polysin and Polyveoline.

Plangger Immanuel I Pinkert Tobias T Wurst Klaus K Magauer Thomas T

Angewandte Chemie (International ed. in English) 20230629 32

We present a concise asymmetric total synthesis (5-8 steps) of nine sesquiterpenoid alkaloids featuring four different tetra-/pentacyclic scaffolds. To this end, a novel, bioinspired indole N-terminated cationic tricyclization has been developed, enabling the divergent synthesis of greenwayodendrines and polysin. Subtle variation of the C2-substituted indole cyclization precursor allowed switching between indole N- and C-termination. For the latter, a subsequent Witkop oxidation enabled conversi ...[more]

PMID: 37318945

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