Glycamine formation via reductive amination of oligosaccharides with benzylamine

This chapter presents a more efficient method for producing glycamine by employing benzylamine as an amino donor. The higher efficiency of this method is because of the ease of Schiff base formation attributable to the lower basicity of benzylamine as well as to the lesser amount of dimeric by-product formed owing to the difficulty of tertiary amine formation. Although this approach requires an extra step of hydrogenolysis to unmask the amino group, the advantages outweigh the minor inconvenience. Although the chapter describes only two examples of oligosaccharide-glycamine formation, and coupling of one of the glycamines to ribonuclease A, the methodology established in the chapter should be applicable to many other oligosaccharide-protein combinations, including sialylated oligosaccharides.