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The Enantioselective Synthesis of Eburnamonine, Eucophylline, and 16'-epi-Leucophyllidine.

ABSTRACT: A synthetic approach to the heterodimeric bisindole alkaloid leucophyllidine is disclosed herein. An enantioenriched lactam building block, synthesized through palladium-catalyzed asymmetric allylic alkylation, served as the precursor to both hemispheres. The eburnamonine-derived fragment was synthesized through a Bischler-Napieralski/hydrogenation approach, while the eucophylline-derived fragment was synthesized by Friedländer quinoline synthesis and two sequential C-H functionalization steps. A convergent Stille coupling and phenol-directed hydrogenation united the two monomeric fragments to afford 16'-epi-leucophyllidine in 21 steps from commercial material.

SUBMITTER: Reimann CE

PROVIDER: S-EPMC8338904 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature

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The Enantioselective Synthesis of Eburnamonine, Eucophylline, and 16'-epi-Leucophyllidine.

Reimann Christopher E CE Ngamnithiporn Aurapat A Hayashida Kohei K Saito Daisuke D Korch Katerina M KM Stoltz Brian M BM

Angewandte Chemie (International ed. in English) 20210706 33

A synthetic approach to the heterodimeric bisindole alkaloid leucophyllidine is disclosed herein. An enantioenriched lactam building block, synthesized through palladium-catalyzed asymmetric allylic alkylation, served as the precursor to both hemispheres. The eburnamonine-derived fragment was synthesized through a Bischler-Napieralski/hydrogenation approach, while the eucophylline-derived fragment was synthesized by Friedländer quinoline synthesis and two sequential C-H functionalization steps. ...[more]

PMID: 34036708

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