Crystal structure of (R,S)-2-hydroxy-4-(methylsulfanyl)butanoic acid

Abstract

The title compound, a major animal feed supplement, abbreviated as HMTBA and alternatively called dl-methionine hydroxy analogue, C5H10O3S, (I), was isolated in pure anhydrous monomeric form. The melting point is 302.5 K and the compound crystallizes in the monoclinic space group P21/c, with two conformationally non-equivalent molecules [(IA) and (IB)] in the asymmetric unit. The crystal structure is formed by alternating polar and non-polar layers running along the bc plane and features an extensive hydrogen-bonding network within the polar layers. The Hirshfeld surface analysis revealed a significant contribution of non-polar H...H and H...S interactions to the packing forces for both molecules.

Keywords

• crystal structure
• methionine hydroxy analog
• 2-hydroxy-4-(methylsulfanyl)butanoic acid
• hmtba
• cas 583–91-5
• hydrogen bonding