SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF THE DILACTONE DERIVATIVE OF GD1a GANGLIOSIDE

Article abstract of DOI:10.1016/0008-6215(88)84089-8

Treatment of GD1a <α-Neu5Ac-(2->3)-β-Gal-(1->3)-β-GalNAc-(1->4)-<α-Neu5Ac-(2->3)>-β-Gal-(1->4)-β-Glc-(1->1)-Cer> with dicyclohexylcarbodi-imide in anhydrous methyl sulfoxide affords 94-98percent of GD1a-dilactone.The involvement of the carboxyl groups of the two sialic acid residues in the lactone rings was proved by ammoniolysis and reduction experiments, which gave ganglioside derivatives containing the amide of sialic acid and N-acetylneuraminulose, respectively. (1)H-N.m.r. spectroscopy showed that the lactone rings involved position 2 of each galactose residue in the ester linkages.