Forssman Glycolipid Variants of Dog Gastric Mucosa. Structure of a Branched Ceramide Octasaccharide

Abstract
A fucose-containing ceramide octasaccharide exhibiting Forssman antigenic activity, and reacting in human H anti-H and anti-A systems, was isolated from water-soluble glycolipids of dog gastric mucosa. Defucosylation of the glycolipid resulted in the loss of H-activity, but had no effect on its Forssman nor blood-group A antigenic activity. The branched structure of glycolipid was identified by partial acid hydrolysis, sequential degradation with specific glycosidases and comparison of the permethylation products of the native and enzyme-degraded compound. The structure of this glycolipid is proposed to be: formula.