Hexasaccharide synthesis

Lam, S N, Gervay-Hague, J, Solution-phase hexasaccharide synthesis using glucosyl iodides, Org. 

Selected reactions with C-l j -toluenesulfonates can be seen in Tables III and IV. In the series of 2,3,4-tri-Oj-benzyl-l-Q-g-tolylsulfonyl-D-glucopyranose derivatives, a few examples of the influence of C-6 substituent, solvent, and structure of reacting alcohol can be seen (Table III, no. 1-5). The S.-pheny 1 carbamate derivative (no. 5) has been used in a stepwise hexasaccharide synthesis (30), and has been used to prepare -aminophenylethyl glucotetraopyranosides for coupling to proteins (31). The stereoselectivity was equally good in the higher members of the series. 

Globo H Hexasaccharide Synthesis How quickly Globo H can be prepared... 

In the furanoside field, the introduction of the last two P-arabino units of a hexasaccharide motif from a bacterial cell wall arabinogalactan was achieved by the sulfoxide method with stereocontrol achieved because of the presence of the 2,3-anhydro group (Scheme 4.62) [368], More recently, the direct stereocontrolled synthesis of arabinofuranosides has been achieved by the sulfoxide method with the aid of a 3,5-0-(di-tert-butylsilylene)-protected donor [369]. 

The versatility of this approach was demonstrated in the synthesis of a variety of oligosaccharides (Scheme 2.7). The synthesis of hexasaccharide 30 (Scheme 2.8) exemplified the use of a glucal acceptor with a secondary alcohol (27) as well as the use of a disaccharide acceptor such as 29. These typical, varied systems can be included in the protocol without complications. 

Scheme 2.8 Solid-phase synthesis of a linear hexasaccharide.

SOLID-PHASE SYNTHESIS OF THE HEXASACCHARIDE GLOBO-H ANTIGEN PROGRESS AND LIMITATIONS... 

Scheme 2.19 Solid-phase synthesis of the globo-H hexasaccharide antigen.

Jain, R. K. Matta, K. L., Chemical synthesis of a hexasaccharide comprising the Lewis(x) determinant linked beta-(l->6) to a linear trimannosyl core and the precursor pentasaccharide lacking fucose. Carbohydr. Res. 1996,282, 101-111. 

Scheme 9 Synthesis of Xylose-Containing Tetra- and Hexasaccharide Building Blocks...

Synthesis of a Hexasaccharide by Formation of the GlcNf -3)Gat Glycoside Bond Intermediate in the Synthesis of Lewis X-Antigens (Le ) [30bI... 

Scheme 4. Synthesis of hexasaccharide 20 using glycosyl phosphates.

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