A fully unprotected (free amine, free acid) L-asparagine glycoamino acid carrying a β-D-GlcNAc residue. This deprotected building block is suited to use as a reference standard, an enzymatic substrate/acceptor, or for conjugation and analytical work rather than direct Fmoc-SPPS. The installed glycan is the N-glycan attachment point, GlcNAcβ-N-Asn, the innermost residue of all N-linked glycans, used to build N-glycopeptides and study N-glycosylation.