Syntheses and evaluation of biantennary oligosaccharide ligands mimicking sialyl Lewis X.

Sialyl Lewis X (1) is known to be a ligand of the cell adhesion molecule E-selectin. We have synthesized several biantennary glycoside-terminated ligands mimicking sialyl Lewis X (1), and evaluated their binding activity to E-selectin using HL-60 cells expressing sialyl Lewis X epitope and human umbilical vein endothelial cells (HUVECs). These compounds were found to possess moderate binding activities to E-selectin. Among them, di-fucoside analog (8) which has no sialic acid carboxylate group was more active than 2, which had both the sialyl-galactose residue and the fucose residue (IC50, 8: 4.7 mM, 2: 11.7 mM). Furthermore, in the rat pleuritic model in vivo induced by carrageenin, 8 was found to reduce neutrophil infiltration at inflammatory lesions.