Synthesis of Tri- and Higher-saccharides

Synthesis of Tri- and Higher-saccharides. — As synthetic methods improve, more attention is being given to the synthesis of trisaccharides, and even more complex saccharides are being produced by specific methods. A major stimulus remains the importance of many compounds of these classes in biological 

Condensation between the acetylated glycosyl bromide derived from the (3-1,4-linked xylobiose and methyl 2,3-anhydro- 3-L-lyxopyranoside afforded a route to the glycoside of the )3-l, 4-xylose-linked trimer, amd the isomeric (1- 3),(l- 4)-]3-linked trisaccharide was obtained by standard glycosylation of a methyl 4-0-j3-D-xylopyranosyl-D-xyloside derivative having a free hydroxyl group at C-3 

Trifluoroacetolysis of human erythrocyte membranes released jS-D-galacto-pyranosyl-(l - 4)-j3-D-galactopyranosyl-(l - 4)-D-glucose and 2-O-(0 -L-fuco-pyranosyl)-3-0-(o D-galactopyranosyl)-D-galactose.  

Thiem s interest in deoxydisaccharides has been extended into related trisaccharides, the glycal derivative (19) having been condensed with methyl 2,3-anhydro-6-deoxy-Q -D-allopyranoside in the presence of iV-iodosuccinimide to give the product (20).  

Ishihara, and S. Tejima, Chem. Pharm. Bull., 1980, 28, 35. 

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