Synthesis of N-(1-deoxyhexitol-1-yl)amino acids, reference compounds for the nonenzymic glycosylation of proteins.
The N-(1-deoxy-D-mannitol-1-yl) and N-(1-deoxy-D-glucitol-1-yl) derivatives of L-valine, L-alanine, L-threonine, and L-leucine were prepared by reductive amination of D-mannose and D-glucose with the appropriate amino acids, in the presence of sodium cyanoborohydride. N epsilon-(1-Deoxy-D-mannitol-1-yl)- and N epsilon-(1-deoxy-D-glucitol-1-yl)-L-lysine were prepared by similar reactions of hexoses with N alpha-tert-butoxycarbonyl and N alpha-benzyloxycarbonyl-L-lysine, followed by removal of the protecting groups. The structures were confirmed by 1H-n.m.r. spectroscopy, which showed that each compound was completely free of its C-2 epimer. The synthetic compounds may be used as reference compounds for the identification of N-(1-deoxyhexitol-1-yl)amino acids formed when N-(1-deoxy-D-fructose-1-yl) groups of nonenzymically glycosylated proteins, of the hemoglobin A1c type, are reduced with sodium borohydride, and the protein is subjected to acid-catalyzed hydrolysis.
D000596:Amino Acids / Q000138:chemical synthesis*; D002250:Carbon Radioisotopes; D006023:Glycoproteins / Q000138:chemical synthesis*; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D009904:Optical Rotation; D013402:Sugar Alcohols / Q000138:chemical synthesis*; D014316:Tritium
D000596:Amino Acids; D002250:Carbon Radioisotopes; D006023:Glycoproteins; D007202:Indicators and Reagents; D013402:Sugar Alcohols; D014316:Tritium