Structural analysis of glycosphinoglipids by high-resolution 1H nuclear magnetic resonance spectroscopy.

The carbohydrate composition of eight glycosphingolipids--glucosylceramide, lactosylceramide, lacto-N-triaosylceramide, neolactotetraosylceramide, IV3Gal alpha neolactotetraosylceramide, globotriaosylceramide, globoside (P-antigen), and Forssman glycolipid (IV3GalNAc alpha GbOse4Cer)--derived from different sources was analyzed by 1H nuclear magnetic resonance at 360 MHz in dimethyl-d6 sulfoxide as solvent. The resonances of all H-1 and H-2 protons as well as those of most of the H-3 and H-4, and of some H-5 protons, of the sugar rings were assigned with the aid of spin decoupling difference spectroscopy. They show regularities related to the type, anomeric configuration, site of glycosidic linkage, and sequence of the component sugars glucose, galactose, glucosamine, and galactosamine. These regularities are thus suited for elucidation of hitherto unknown structure of more complex glycosphingolipids.