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Enantioselective total synthesis of tricyclic myrmicarin alkaloids.

ABSTRACT: [reaction: see text] An enantioselective gram-scale synthesis of a key dihydroindolizine intermediate for the preparation of myrmicarin alkaloids is described. Key transformations in this convergent approach include a stereospecific palladium-catalyzed N-vinylation of a pyrrole with a vinyl triflate, a copper-catalyzed enantioselective conjugate reduction of a beta-pyrrolyl enoate, and a regioselective Friedel-Crafts reaction. The synthesis of optically active and isomerically pure samples of (4aR)-myrmicarins 215A, 215B, and 217 in addition to their respective C4a-epimers is presented.

SUBMITTER: Movassaghi M

PROVIDER: S-EPMC2992882 | biostudies-literature | 2005 Sep

REPOSITORIES: biostudies-literature

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Enantioselective total synthesis of tricyclic myrmicarin alkaloids.

Movassaghi Mohammad M Ondrus Alison E AE

Organic letters 20050901 20

[reaction: see text] An enantioselective gram-scale synthesis of a key dihydroindolizine intermediate for the preparation of myrmicarin alkaloids is described. Key transformations in this convergent approach include a stereospecific palladium-catalyzed N-vinylation of a pyrrole with a vinyl triflate, a copper-catalyzed enantioselective conjugate reduction of a beta-pyrrolyl enoate, and a regioselective Friedel-Crafts reaction. The synthesis of optically active and isomerically pure samples of (4 ...[more]

PMID: 16178549

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