Studies on glyceryl esters. I. The formation of urea inclusion compounds with 1‐monoglycerides

Abstract

The 1‐monoglycerides of saturated even fatty acids from caprylic to stearic have been shown to form inclusion compounds with urea. The preparation of pure adducts and the crystal size and form of the various members of the series have been described, and the molecular ratios of urea to lipid, and also the ‘dissociation’ and ‘exudation’ temperatures have been determined.

Nonionic Urea Surfactants: Influence of Hydrocarbon Chain Length and Positional Isomerism on the Thermotropic and Lyotropic Phase Behavior

“…After this key historical event, synthetic urea has functioned in many roles. Urea inclusion compounds have served as separation media − and have provided an insight into the nature of hydrogen bonding for two-dimensional crystal engineering. − The ability of the urea molecule to participate in hydrogen-bonded α-networks via the carbonyl group of one unit and two hydrogen atoms of an adjacent unit (bifurcated hydrogen bonding) provides the supramolecular “cement”. Urea is a chaotropic agent and has progressed the understanding of hydrophobic interaction in aqueous solutions.…”