First Synthesis of Heparan Sulfate Tetrasaccharides Containing both N‐Acetylated and N‐Unsubstituted Glucosamine—Search for Putative 10E4 Epitopes

A methodology allowing the differentiation of azido groups in protected oligosaccharides was optimized. It allowed the first synthesis of tetrasaccharides 1 and 2 containing both N-acetylated and N-unsubstituted glucosamine, as well as glucuronic and/or iduronic acid residues. These tetrasaccharides were then examined for their ability to interact with 10E4, an antibody recognizing early lesions in the brain of scrapie prion-infected mice.