On the basis of the highly branched ovomucoid-type undecasaccharide that had been shown previously to be an endogenous ligand for CD69 leukocyte receptor, a systematic investigation of smaller oligosaccharide mimetics was performed based on linear and branched N-acetyl-D-hexosamine homooligomers prepared synthetically using hitherto unexplored reaction schemes. The systematic structure-activity studies revealed the tetrasaccharide GlcNAcβ1-3(GlcNAcβ1-4)(GlcNAcβ1-6)GlcNAc (compound 52) and its α-benzyl derivative 49 as the best ligand for CD69+ with IC50 as high as 10-9 M.
This compound thus approaches the affinity of the classical high-affinity neoglycoprotein ligand GlcNAc23BSA.