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Synlett 2010(18): 2802-2804  
DOI: 10.1055/s-0030-1259008
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Synthesis of Onychine and Formal Synthesis of Eupolauridine via the Vinylogous Aza-Morita-Baylis-Hillman Reaction

Kristen N. Clary, Thomas G. Back*
Department of Chemistry, University of Calgary, Calgary, AB, T2N 1N4, Canada
Fax: +1(403)2899488; e-Mail: tgback@ucalgary.ca;
Further Information

Publication History

Received 2 September 2010
Publication Date:
14 October 2010 (online)

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Abstract

A concise and efficient synthesis of the antimycotic alkaloid onychine was developed, based on the vinylogous aza-Morita-Baylis-Hillman reaction of N-(benzylidene)benzenesulfonamide with methyl 2,4-pentadienoate, followed by intramolecular conjugate addition, Friedel-Crafts acylation, methyl cuprate addition, and aromatization.

Key Words

alkaloids - onychine - aza-Morita-Baylis-Hillman ­reaction - cyclization - cuprates

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For experimental procedures and characterization data for new compounds and the final product 1, see the Supporting Information.