Synthesis of a neoglycoprotein containing the Lewis X analogous trisaccharide beta-D-GalpNAc-(1-->4)[alpha-L-Fucp-(1-->3)]-beta-D-GlcpNAc.
The trisaccharide allyl glycoside 36 and related disaccharide part structures have been prepared using the 2-trichloroacetamido-2-deoxy-alpha-D-galactopyranosyl trichloroacetimidate derivative 9 as glycosyl donor under promotion with TMSOTf or Sn(OTf)2, respectively, to produce the beta-(1-->4) linkage to suitably protected glucosamine derivatives in fair yields. Fucosylation was effected employing the ethyl 1-thio glycosyl donor 20 in the presence of IDCP. Deprotection of the intermediates afforded the disaccharide allyl glycosides beta-D-GalpNAc-(1-->4)- beta-D-GlcpNAc 13, beta-D-GalpNClAc-(1-->4)-beta-D-GlcpNAc 14, alpha-L-Fucp-(1-->3)-beta-D-GlcpNAc 24, alpha-L-Fucp-(1-->4)-beta-D- GlcpNAc 31 and the branched trisaccharide allyl glycoside beta-D-GalpNAc-(1-->4)[alpha-L-Fucp-(1-->3)]-beta-D-GlcpNAc 36. The trisaccharide which corresponds to a structural motif occurring in N-glycoprotein glycans from human urokinase, human recombinant protein C, phospholipase A2 as well as O-glycans, was converted into a neoglycoprotein following introduction of a cysteamine-derived spacer group and subsequent activation with thiophosgene.
Institute of Chemistry, University of Agricultural Sciences Vienna, Austria.
J
J
Bartek
R
R
Müller
P
P
Kosma
D002240:Carbohydrate Sequence; D019040:E-Selectin / Q000378:metabolism; D006023:Glycoproteins / Q000138:chemical synthesis*; D006027:Glycosides / Q000138:chemical synthesis; D006801:Humans; D008024:Ligands; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D009844:Oligosaccharides / Q000378:metabolism; D010741:Phospholipases A / Q000737:chemistry; D054467:Phospholipases A2; D011134:Polysaccharides / Q000737:chemistry; D011486:Protein C / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D000080506:Sialyl Lewis X Antigen; D014312:Trisaccharides / Q000138:chemical synthesis*; D014568:Urokinase-Type Plasminogen Activator / Q000737:chemistry
D019040:E-Selectin; D006023:Glycoproteins; D006027:Glycosides; D008024:Ligands; C114828:N-acetylgalactosaminyl-1-4-(fucosopyranosyl-1-3)-N-acetylglucosamine; D009844:Oligosaccharides; D011134:Polysaccharides; D011486:Protein C; D000080506:Sialyl Lewis X Antigen; D014312:Trisaccharides; D012710:Serum Albumin, Bovine; D010741:Phospholipases A; D054467:Phospholipases A2; D014568:Urokinase-Type Plasminogen Activator