SYNTHESIS OF GLYCOSYLAMINES: IDENTIFICATION AND QUANTIFICATION OF SIDE PRODUCTS

The synthesis of some glycosylamines (1-amino-1-deoxy D-glucose, 1-amino-1-deoxy-D-galactose and 1-amino-1-deoxylactose) was carried out by treatment of the corresponding reducing sugars with ammonium hydrogencarbonate in concentrated ammonia. The reaction mixture was first analyzed by capillary electrophoresis with indirect absorbance detection and high performance anion-exchange chromatography with pulsed amperometric detection. Beside glycosylcarbamate, a known reaction by-product, fructose and lactulose were detected during the synthesis of 1-amino-1-deoxyglucose and 1-amino-1-deoxylactose, respectively. Quantification of glycosylamines was carried out by micellar electrokinetic chromatography with UV detection of their 9-fluorenylmethyloxycarbonyl (Fmoc) derivatives; lactulosylamine was thus detected in the synthesis mixture of 1-amino-1-deoxylactose. The Fmocglycosylamines were easily purified from the other components of the crude synthesis mixtures.