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Updated: Jun 17, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Synthesis and assignment of absolute configuration of the iridoid 9-deoxygelsemide
Alessandro D'Alfonso1, Maurizio Pasi, Alessio Porta
1Dipartimento di Chimica Organica, Università di Pavia, Via Taramelli 10, 27100 Pavia, Italy.
Abstract:
The first enantioselective synthesis of 9-deoxygelsemide, belonging to a rare group of iridoids isolated from Gelsemium plants, is described. The key synthetic steps are a variant of the Woodward-Prevost reaction to install the characteristic cis-alpha-1,2-dioxygenated system at C-6 and C-7 with complete diastereoselectivity. Construction of the dihydropyran ring was achieved via formylation of lactone I, followed by dehydration of the corresponding lactol. The synthesis allowed assignment of absolute configuration to 9-deoxygelsemide and related iridoids.
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