SYNTHESIS OF GLYCOSYLAMINES: IDENTIFICATION AND QUANTIFICATION OF SIDE PRODUCTS

Abstract

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.

ACKNOWLEDGMENT

This work was supported by a research grant of F.B.C. S.r.l. to the Department of Biochemistry, Biophysics and Macromolecular Chemistry of the University of Trieste and by Grant no. 9903263827 of Italian MURST (Progetti di Interesse Nazionale). The authors thank Prof. Cataldi (Department of Chemistry, University of Basilicata) for the use of the HPAEC-PAD instrument.