Abstract: A transamination reaction of glycosyl-1-amine with a nucleophilic reagent containing an --NH.sub.2 or --NHNH.sub.2 group is used to prepared a broad spectrum of glycoconjugates by substitution of the 1-amino group. The substitution reaction does not adversely affect the ring structure of the sugar as does the prior art reductive amination reaction. Suitable nucleophilic reagents are nucleophiles having a chromophore group, a fluorophore group, a chemiluminescent group, a lipid, an amino acid or peptide moiety, biotin, a drug and a linker/spacer group and an affinity label. The ratio of glycosyl-1-amine to nucleophilic reagent is in the range of from about 1:1 to about 1:2 by weight.