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Updated: May 24, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
1-[(1-ethoxypropylidene)amino]-2-ethyl-4-(4-hydroxybenzyl)imidazol-5(4H)-one
Krzysztof Ejsmont1, Agnieszka Kudelko, Wojciech Zieliński
1Faculty of Chemistry, Opole University, Opole, Poland. eismont@uni.opole.pl
Abstract:
The racemic title compound, C(17)H(23)N(3)O(3), isolated from the reaction of L-(-)-tyrosine hydrazide with triethyl orthopropionate in the presence of a catalytic quantity of p-toluenesulfonic acid (p-TsOH), crystallizes with Z' = 1 in a centrosymmetric monoclinic unit cell. The molecule contains two planar fragments, viz. the benzene and imidazole rings, linked by two C-C single bonds. The dihedral angle between the two planes is 59.54 (5)° and the molecule adopts a synclinal conformation. The HOMA (harmonic oscillator model of aromaticity) index, calculated for the benzene ring, demonstrates no substantial interaction between the two π-electron delocalization regions in the molecule. In the crystal structure, there is an O-H...N hydrogen bond that links the molecules along the c axis.
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