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Total synthesis of the Lycopodium alkaloid serratezomine A using free radical-mediated vinyl amination to prepare a ?-stannyl enamine linchpin.

ABSTRACT: Serratezomine A is a member of the structurally diverse class of compounds known as the Lycopodium alkaloids. The key supporting studies and successful total synthesis of serratezomine A are described in this account. Significant features of the synthesis include the first application of free radical mediated vinyl amination and Hwu's oxidative allylation in a total synthesis and an intramolecular lactonization via a transannular S(N)i reaction. Minimal use of protecting groups and the highly diastereoselective formation of a hindered, quaternary stereocenter using an umpolung allylation are also highlights from a strategy perspective. Observation of quaternary carbon epimerization via a retro-Mannich/Mannich sequence highlights the additional challenge presented by the axial alcohol at C8 in serratezomine A.

SUBMITTER: Pigza JA

PROVIDER: S-EPMC3565160 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Total synthesis of the Lycopodium alkaloid serratezomine A using free radical-mediated vinyl amination to prepare a β-stannyl enamine linchpin.

Pigza Julie A JA Han Jeong-Seok JS Chandra Aroop A Mutnick Daniel D Pink Maren M Johnston Jeffrey N JN

The Journal of organic chemistry 20121228 3

Serratezomine A is a member of the structurally diverse class of compounds known as the Lycopodium alkaloids. The key supporting studies and successful total synthesis of serratezomine A are described in this account. Significant features of the synthesis include the first application of free radical mediated vinyl amination and Hwu's oxidative allylation in a total synthesis and an intramolecular lactonization via a transannular S(N)i reaction. Minimal use of protecting groups and the highly di ...[more]

PMID: 23273261

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