| Abstract: | Reactions that are relevant to the cleavage, by hydrazinolysis, of O‐linked oligosaccharides from glycoproteins were studied using dehydroalanine derivatives as models of the intermediates formed from O‐glycosylated serine residues. Conjugate addition of hydrazine followed by cyclisation to form pyrazolidinones, if occurring during glycoprotein hydrazinolysis, could reduce the yield of released oligosaccharide. However, N‐acetyldehydroalanine amide derivatives, which modelled the dehydroalanine derivatives believed to be intermediates in the hydrazinolysis of glycoproteins containing O‐linked oligosaccharides, underwent conjugate addition but no cyclisation. Copyright © 1999 European Peptide Society and John Wiley & Sons, Ltd. |
