AN IMPROVED METHOD FOR THE LIQUID CHROMATOGRAPHY OF THE 1-DEOXY-1-(2-PYRIDYLAMINO)ALDITOL DERIVATIVES OF OLIGOSACCHARIDES AND ITS APPLICATION TO STRUCTURAL STUDIES OF THE CARBOHYDRATE MOIETIES OF GLYCOPROTEINS

Article abstract of DOI:10.1016/0008-6215(85)85202-2

The 1-deoxy-1-(2-pyridylamino)alditols prepared by reductive amination of lactose, 2-acetamido-2-deoxy-D-glucose, and 2,5-anhydro-D-mannose have been characterised, and the efficiency of the reductive amination procedure, especially with 2,5-anhydro-D-mannose and 2-amino-2-deoxy-D-glucose hydrazone as starting materials, has been studied.The latter compound, which is a model for the oligosaccharide hydrazones released from glycoproteins and glycopeptides by hydrazinolysis, was first N-acetylated and the hydrazone group was found to be removed hydrolytically when a cation-exchange resin was used for deionisation.Such loss of the hydrazone group is desirable because the N-acetylated hydrazone was not efficiently derivatised by reductive amination.An amine-modified silica column was used to separate the components of a mixture of the pyridylamino derivatives of oligosaccharides from mono- to dodeca-saccharide in 20 min.A neutral fluorescent by-product, formed in all reductive aminations, was identified as (2-amino-1-pyridyl)cyanoborane and was eluted well before monosaccharide derivatives and thus did not interfere with the analysis.