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Updated: Jun 16, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Modular Maleimide Synthesis from Ynamides
Thibault Heymans1, Loïc Durand-Baudet1, Yohann Landrain1
1Laboratoire de Chimie Organique, Service de Chimie et PhysicoChimie Organiques, Université libre de Bruxelles (ULB), Avenue F. D. Roosevelt 50, CP160/06, 1050 Brussels, Belgium.
Abstract:
A general and efficient strategy for the synthesis of maleimides from readily accessible ynamides and α-ketoesters via in situ generated lithiated ketenimines, engaging in a cascade sequence involving formal anionic (2 + 2) cycloaddition, cycloreversion, and cyclocondensation, is reported. This method enables rapid access to a wide range of densely functionalized maleimides with excellent functional group tolerance, under conditions allowing either retention or removal of the N-protecting group. The resulting scaffolds can be readily diversified, notably through a "nitrogen switch" strategy, to access distinct heterocycles. The power of this approach is demonstrated in the concise syntheses of denigrin A and aqabamycin A, as well as the first unified and divergent synthesis of antrodins A-C, highlighting its potential as a versatile platform for the rapid construction of functional maleimide architectures.
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