A β-D-N-acetylglucosamine (GlcNAcβ) ligand equipped with a terminal alkyne through a hydrophilic PEG3 spacer. The alkyne couples to azide-functionalized partners via copper-catalyzed azide-alkyne cycloaddition (CuAAC), forming stable 1,2,3-triazole linkages. This compound provides a β-N-acetylglucosamine (GlcNAcβ) building block for glycoconjugate synthesis and the construction of probes for GlcNAc-recognizing proteins and lectins; it is also relevant to O-GlcNAc and N-glycan biosynthesis research and a substrate for galactosyltransferases.