Synthesis of the Lewis b pentasaccharide and a HSA-conjugate thereof

Helicobacter pylori, a gastric pathogen, binds to various blood group antigens, including the Lewis types, present in the gastric tissue and a relation between the presentation of the ligands and the overall strength of binding has been assumed. Synthetic Lewis b tetra- and hexasaccharide conjugates are available but not the analogous pentasaccharide. An efficient synthesis of the amino spacer equipped Lewis b pentasaccharide, 3-aminopropyl α-l-fucopyranosyl-(1→2)-β-d-galactopyranosyl-(1→3)-[α-l-fucopyranosyl-(1→4)]-2-acetamido-2-deoxy-β-d-glucopyranosyl-(1→3)-β-d-galactopyranoside, is presented to enable further investigation of the carbohydrate recognition process of H. pylori.