Linear Homotrisaccharides

2 Linear Homotrisaccharides. - Maltose, cellobiose and lactose as 0-pro-tected p-thioglycosides have been tethered via their 0-2 to 0-3 of benzyl 6-0-benzyl-2-O-benzoyl-a-D-glucopyranoside. Cyclization induced by NIS gave a-linked trisaccharide products in about 60% yield. This approach has therefore given access to a-D-Glc-(l- 4)-a-D-Glc-(l- 4)-D-Glc, p-D-Glc-(l- 4)-a-D-Glc-(1—4)-d-G1c and p-D-Gal-(l- 4)-a-D-Glc-(l- 4)-D-Glc.3  

The p-(l- 6), p-(1 6) linked trimers (and tetramers) of Glc and Gal and the a-(1 6), a-(l- 6) analogues of Man have been made by use of the 1,2-orthoester approach. The 4-pentenyl P-glycoside of the p-(l- 6) linked glucotriose was prepared via the resin-bound 2 and cleaved from the resin by elimination of bromine and application of Grubbs catalyst as an alkene cleaving agent. By 

1 Linear Homotrisaccharides. - The nephritogenoside trisaccharide unit a-D-Glc-(1- 6)-P-d-G1c-(1- 6)-a-D-Glc has been prepared by application of the glycosyl sulfoxide procedure. Cellotriose can be made from cellobiose by use of a sesame seed transferase which also transfers from other disaccharide substrates. Treatment of highly concentrated aqueous solutions of D-mannose with an a-mannosidase from Aspergillus niger has resulted in the isolation of the trimers a-D-Man-(l- 2)-a-D-Man-(l- 6)-D-Man and a-D-Man-(l 2)-a-D-Man-(1 - 2)-D-Man, and this latter trisaccharide has been formally synthesized by Fraser-Reid and colleagues in studies of the mannan components of phosphatidylinositol membrane anchors. In the course of the work they used the orthoesters 4 as versatile synthetic intermediates.  

Carbohydrate Chemistry, Volume 30 The Royal Society of Chemistry, 1998 

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Linear Homotrisaccharides.— The non-reducing, trehalose-containing trisaccharide... 

Linear Homotrisaccharides.—4-0-a-D-Glucopyranosyl-a,oi-trehalose has been made by... 

Trisaccharides Linear Homotrisaccharides Linear Heterotrlsaccharides Branched Homotrisaccharides Branched Heterotrisaccharides... 

Linear Homotrisaccharides.— Pyrolysis of sucrose at 100 C in the presence of citric acid caused the formation of the fructofuranosyl cation and thence the six non-reducing trisaccharides comprising sucrose with fructofuranose a- and - bonded to C-6, C-1 and C-6 4-0-a-D-Glucopyranosyl-c(,a-trehalose was made by use of perbenzylated glucosyl fluoride. ... 

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