Determination of position of substitution on 2-acetamido-2-deoxy-D-galactosyl residues in glycolipids

Abstract

The substitution site on 2-acetamido-2-deoxy-D-galactosyl residues in oligosaccharide chains of glycolipids was determined by permethylation of the glycolipid with methyl iodide in the presence of dimethylsulfinyl carbanion, methanolysis of the permethylated product under mild conditions, acetylation with acetic anhydride-pyridine, and identification of the resulting substituted methyl glycosides of 2-deoxy-2(N-methylacetamido)-D-galactose by g.l.c. The method was applied to glycolipids of known structure, including normal brain ganglioside, Tay-Sachs ganglioside, and Forssman glycolipid.