Pentafluorophenyl esters for temporary carboxyl group protection in solid phase synthesis of N-linked glycopeptides
The compound Ac3GlcNAcβ1-NH-Fmoc (3) was synthesized and transformed into the β-glucosyl amine (1) which was subsequently acylated with Fmoc-Asp(Cl)-O-Pfp (5) prepared from the readily available Fmoc-Asp(O-tBu)-O-Pfp (4). The resulting Fmoc-Asn