摘要:
Recent research has revealed the presence of asparagine (Asn)-linked (N-linked) glycoproteins in certain prokaryotes. In this paper, we describe the chemical synthesis of a novel N-glycan derived from Campylobacter jejuni, a heptasaccharide composed of Asn-linked bacillosamine (Bac), repeating GalNAc, and branching Glc, namely GalNAc-alpha(1,4)-GalNAc-alpha(1,4)-[Glc-beta(1,3)-] GalNAc-alpha(1,4)-GalNAc-alpha(1,4)-GalNAc-alpha(1,3)-Bac. The synthesis started from a Bac-acceptor, which was consecutively glycosylated with 4-O-pentafluoropropionyl (PFP) protected donors to give heptasaccharide. Reduction of azide groups was followed by debenzylation to complete the synthesis of the target oligosaccharide. (c) 2007 Elsevier Ltd. All rights reserved.