(S)-1-Methyl-2-oxoimidazolidine-4-carboxylic Acid

Abstract

first_pagesettingsOrder Article Reprints Open AccessShort Note (S)-1-Methyl-2-oxoimidazolidine-4-carboxylic Acid by Ashley L. Dey,Majid Motevalli,Isaac Abrahams andPeter B. Wyatt *ORCID Department of Chemistry, Joseph Priestley Building, Queen Mary University of London, Mile End Road, London E1 4NS, UK * Author to whom correspondence should be addressed. Molbank 2024, 2024(2), M1835; https://doi.org/10.3390/M1835 Submission received: 25 May 2024 / Accepted: 8 June 2024 / Published: 12 June 2024 Downloadkeyboard_arrow_down Browse Figures Versions Notes Abstract (S)-1-Methyl-2-oxoimidazolidine-4-carboxylic acid 1 is an analog of (S)-pyroglutamic acid, a key component of naturally occurring peptide hormones and synthetic pharmaceutical candidates. The reaction of (S)-2-amino-3-(methylamino)propionic acid with COCl2 and aqueous NaHCO3 followed by ion exchange afforded 1, which was recrystallized from acetonitrile and then characterized by IR, 1H NMR, 13C NMR, polarimetry, elemental microanalysis, high-resolution mass spectrometry and single-crystal X-ray diffraction. The acid 1 crystallized in the orthorhombic chiral space group P212121 with cell constants a = 6.2275(4) Å, b = 8.3963(5) Å, c = 24.9490(14) Å. The X-ray crystal structure revealed that two distinct conformers of 1 occur at alternating positions within helices which are supported by hydrogen bonds. Each molecule of 1 is linked to its two neighbors in the helix by a total of three hydrogen bonds, and four molecules of 1 are contained within each turn of the helix. The pattern of hydrogen bonds illustrates a preference for the carboxylic acid group to act as a hydrogen bond donor and for the urea unit to be a hydrogen bond acceptor.