424820-76-8

Upstream product

• 127061-09-0 phenyl 4,6-di-O-benzylidene-2-deoxy-2-phthalimido-1-thio-β-D-glucopyranoside 
• 183875-25-4 phenyl 2,3,4-tri-O-benzyl-1-thio-α-L-fucopyranoside 
• 187233-24-5 phenyl 6-deoxy-1-thio-β-L-galactopyranoside 
• 136882-36-5 2-((2S,3R,4R,5S,6R)-4,5-Dihydroxy-6-hydroxymethyl-2-phenylsulfanyl-tetrahydro-pyran-3-yl)-isoindole-1,3-dione 
• 100-39-0 benzyl bromide 
• 1125-88-8 benzaldehyde dimethyl acetal 

Downstream Products

• 220691-39-4 phenyl O-(2,3,4-tri-O-benzyl-α-L-fucopyranosyl)-(1-3)-4-O-(acetyl-1-13C)-6-O-benzyl-2-deoxy-2-phthalimido-1-thio-β-D-glucopyranoside 
• 639507-67-8 phenyl 2,3,4-tri-O-benzyl-α-L-fucopyranosyl-(1->3)-2-acetamido-4,6-O-benzylidene-2-deoxy-1-thio-β-L-glucopyranoside 

Relevant academic research and scientific papers

Control of disaccharide conformation by π-stacking

The conformations of a series of derivatives of the disaccharide α-L-fucopyranosyl-(1→3)-2-acetamido-2-deoxy-D-glucopyranoside, part of the Lex determinant, were studied by molecular modelling using the MM3* forcefield and by 1H NMR spectroscopy. Unusually shielded O- benzyl protons were observed in the 1H NMR spectrum of phenyl 2,3,4-tri-O-benzyl-α-L-fucopyranosyl-(1→3)- 2-deoxy-2-phthalimido-1-thio-α-D-glucopyranoside and assigned to the 2-O-benzyl group. This observation was explained by a shift in the population of the conformational mixture present about the glycosidic linkage from the positive Ψ region in the unsubstituted disaccharide to the negative Ψ region induced by π-stacking between the phthalimide and the 2-O-benzyl phenyl ring. The experimental nuclear Overhauser enhancements confirm the accuracy of the calculations.

Solid-phase synthesis of oligosaccharides and on-resin quantitative monitoring using gated decoupling 13C NMR

A general strategy for solid-phase oligosaccharide synthesis capable of nondestructive quantitative monitoring has been developed. The synthesis was carried out on TentaGel using thioglycosides as glycosylating agents and dimethylthiomethylsulfonium triflate as the activator. An acylsulfonamide linker was introduced to cleave the oligosaccharide from the resin. The solid-phase reactions were monitored quantitatively by using the inverse gated decoupling technique of 13C NMR, where two 13C-enriched markers were used to monitor the reactions: one was 13C-enriched glycine incorporated as a part of the linker and as an internal standard, and the other was a 13C-enriched acetyl group used as a protecting group of the glycosylation reagent. A representative synthesis of sialyl Lewis X branched tetrasaccharide was demonstrated.