Synthesis and alpha-adrenergic binding ligand affinities of 2-iminoimidazolidine derivatives
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Updated: Oct 16, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
J Chang-Fong1, K Benamour, B Szymonski
1Groupe de Pharmacochimie Moléculaire, UMR 5063-CNRS, Faculté de Pharmacie, Université J. Fourier, La Tronche, France.
Abstract:
In order to obtain possible veinotonic drugs acting through alpha2 receptor activation, we prepared clonidine analogues in which the 2-imino-imidazolidine was attached to various aliphatic or aromatic heterocycles. Among them, the two benzopyranic derivatives 16 and 22 exhibited interesting affinities (19 and 95 nM respectively on [3H]rauwolscine binding, compared to 35 nM for clonidine). Their affinity for alpha1 receptors was found to be much lower: 7570 and 5030 nM for 16 and 22 respectively, suggesting 16 to be 400 times more selective for alpha2 than for alpha1-adrenoceptors.
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