(S)-1,2-diacyl-3-acetins: Optically active triglycerides fromEuonymus verrucosus seed oil

Abstract

The seed oil ofEuonymus verrucosus Scop., family Celastraceae, contains more than 90% 1,2-diacyl-3-acetins (monoacetotriglycerides). The constituent triglyceride acids, other than acetic, are the usual long-chain fatty acids.Thin-layer chromatography (TLC), infrared (IR) and hydrolysis with pancreatic lipase indicate that the acetic acid is esterified exclusively on the outer glycerol carbon atoms. The isolated mixed monoacetotriglycerides exhibit optical rotation caused by asymmetry of the central glycerol carbon atom. Comparison with synthetic products of known configuration shows that the natural material is essentially all (S)-1,2-diacyl-3-acetin.IR, TLC and GLC analyses indicate the presence of monoacetotriglycerides in seven other species of Celastraceae and five species in three other plant families in amounts from 13 to 98%.