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Unified total syntheses of fawcettimine class alkaloids: fawcettimine, fawcettidine, lycoflexine, and lycoposerramine B.

ABSTRACT: The total syntheses of the lycopodium alkaloids fawcettimine, fawcettidine, lycoflexine, and lycoposerramine B have been accomplished through an efficient, unified, and stereocontrolled strategy that relies on a Diels-Alder reaction to construct the cis-fused 6,5-carbocycles with one all-carbon quaternary center. Access to the enantioselective syntheses of both antipodes of those alkaloids can be achieved by kinetic resolution of the earliest intermediate via a Sharpless asymmetric dihydroxylation (Sharpless AD). Compared to existing approaches to these alkaloids, our synthetic route possesses superior stereocontrol over the C-4 and C-15 stereogenic centers as well as allowing for more functional variation on the 6-membered ring.

SUBMITTER: Pan G

PROVIDER: S-EPMC3448369 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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Unified total syntheses of fawcettimine class alkaloids: fawcettimine, fawcettidine, lycoflexine, and lycoposerramine B.

Pan Guojun G Williams Robert M RM

The Journal of organic chemistry 20120507 10

The total syntheses of the lycopodium alkaloids fawcettimine, fawcettidine, lycoflexine, and lycoposerramine B have been accomplished through an efficient, unified, and stereocontrolled strategy that relies on a Diels-Alder reaction to construct the cis-fused 6,5-carbocycles with one all-carbon quaternary center. Access to the enantioselective syntheses of both antipodes of those alkaloids can be achieved by kinetic resolution of the earliest intermediate via a Sharpless asymmetric dihydroxylati ...[more]

PMID: 22519642

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