Synthesis of a biotinylated penta-α-(1→6)-d-glucoside based on the rational design of an α-stereoselective glucosyl donor

Abstract

Rational design of a protecting group pattern in a glucosyl donor allows for the α-selective synthesis of biotinylated pentasaccharides corresponding to the fragment of the α-(1→6)-glucans of Helicobacter pylori.

Chemical Synthesis and Evaluation of Exopolysaccharide Fragments Produced by <i>Leuconostoc mesenteroides</i> Strain NTM048

“…A variety of glycosylation reactions have been developed to construct the α-linkage and have been applied to the synthesis of α-glucan oligomers. 9,10) Although the synthesis of similar linear α-(1→ 6)-linked oligomers was reported by several groups, [11][12][13][14][15][16][17] the facile synthesis of oligomers containing an α-(1→ 3)-branched structure is still limited. 14,17) We synthesized tetrasaccharide 2 (Chart 1), following the strategy reported by Lam and Gervay-Hague 12,13) where the α-(1→ 6)-linked glucosyl oligomers were synthesized using 6-O-acetyl-2,3,4-tri-O-benzylglucopyranosyl iodide as a glycosyl donor.…”

Chemical Synthesis and Application of Biotinylated Oligo-α-(1 → 3)-d-Glucosides To Study the Antibody and Cytokine Response against the Cell Wall α-(1 → 3)-d-Glucan of Aspergillus fumigatus

“…The main problem in the assembly of oligoglucoside chains of this type is the 1,2- cis stereoselectivity in the synthesis of α-glucosides, which is known to be a nontrivial task . To develop new methods for 1,2- cis -selective glycosylations, we have been constantly investigating the effect of stereoelectronic properties and other electronic interactions of protecting groups on the stereochemistry of the glycosylation, − and in particular, we have studied the possibility of remote anchimeric assistance. To achieve this goal, the use of the corresponding 6- O- benzoylated glycosylating agents was explored.…”

“…To achieve this goal, the use of the corresponding 6- O- benzoylated glycosylating agents was explored. The benzoyl group at O - 6 is thought to possess an α-stereodirecting effect because of its ability to shield the β-face of the reaction intermediate, an oxocarbenium ion, the structure of which controls the stereochemistry of the glycosylation. ,,, …”

“…The benzoyl group at O-6 is thought to possess an α-stereodirecting effect because of its ability to shield the β-face of the reaction intermediate, an oxocarbenium ion, the structure of which controls the stereochemistry of the glycosylation. 6,10,11,14 We successfully employed a stereoselective α-glucosylation for the assembly of short α-glucooligosaccharide chains using mono-and disaccharide glucosyl donors. 6,10,14,15 Thus, we investigated the applicability of the discussed methods for achieving stereocontrolled α-glucosylations with large oligosaccharide glycosyl donors.…”

Efficient Strategy for α-Selective Glycosidation of d-Glucosamine and Its Application to the Synthesis of a Bacterial Capsular Polysaccharide Repeating Unit Containing Multiple α-Linked GlcNAc Residues

“…Inspired by the previous reports, we have recently developed a highly selective α-glucosylation method based on the synergistic α-directing effects of the toluenesulfenyl chloride (TolSCl)-silver triflate (AgOTf) promotion system and the β-shielding or remote participation effect of protecting groups at the donor 6- O -position . This method has exhibited broad applicability and great potential in one-pot synthesis of complex oligosaccharides .…”