Structural Analysis of a Novel Triphosphonoglycosphingolipid from the Egg of the Sea Hare, Aplysia kurodai

: A novel phosphonoglycosphingolipid which contains three residues of 2-aminoethylphosphonate (2-AEP) was isolated from eggs of a sea gastropoid, Aplysia kurodai, and its structure was identified as follows. [see text] The major aliphatic components of ceramide were palmitic acid, stearic acid, 4-sphingenine, and 16-methyl-4-sphingenine. Antibodies which recognize 3-O-methylgalactose linked beta-glycosidically to phosphonoglycosphingolipids failed to react to the egg glycolipid. By comparing 1H-NMR spectra of native and HF-treated glycolipids, steric interactions of two residues of 2-AEP with ring protons of the glucose and the internal galactose were indicated.