Patent ID: 8399656

Claim:
A process for preparing glycopeptide having at least two asparagine-linked oligosaccharides at a desired position of the peptide chain thereof, the process comprising: (a) esterifying a hydroxyl group of a resin having the hydroxyl group and a carboxyl group of an amino acid having amino group nitrogen protected with a fat-soluble protective group, (b) removing the fat-soluble protective group to form a free amino group, (c) amidating the free amino group and a carboxyl group of an amino acid having amino group nitrogen protected with a fat-soluble protective group, (d) removing the fat-soluble protective group to form a free amino group, (e) repeating the steps (c) and (d) at least once, (f) amidating the free amino group and a carboxyl group of the asparagine portion of an asparagine-linked oligosaccharide having amino group nitrogen protected with a fat-soluble protective group, (g) removing the fat-soluble protective group to form a free amino group, (h) amidating the free amino group and a carboxyl group of an amino acid having amino group nitrogen protected with a fat-soluble protective group, (i) repeating the steps (g) and (h) at least once, (j) removing the fat-soluble protective group to form a free amino group, and (k) cutting off the resin with an acid; wherein the steps (f) of amidating the free amino group and a carboxyl group of the asparagine portion of an asparagine-linked oligosaccharide having amino group nitrogen protected with a fat-soluble protective group and (g) of removing the fat-soluble protective group to form a free amino group are repeated after the step (g) or (j), and wherein at least one of the asparagine-linked oligosaccharides in the step (f) has a residue of sialic acid or a derivative thereof at a terminal end thereof.