Orthogonal Strategy in Oligosaccharide Synthesis

Much effort has been devoted to identification of the funetions of the oligosaccharides found on the cell surface, where they covalently attached to a variety of organic molecules such as proteins and lipids. Because of the diversity of oligosaccharide structures, they are often described as the finger print of a certain cell. The possibility that the complex structures are directly related to their functions has prompted many synthetic chemists to synthesize glycoconjugates. 

During the last two decades the technology for the synthesis of these structures has, therefore, improved dramatically. The key reaction in the construction of oligo- 

2-trans glycoside formation by means of a C-2 participating group [1, 2]  

2) axial glycoside formation resulting from the anomeric effect [3]  

3) equatorial glycoside formation using solvation of the carbonium cation by acetonitrile [4]  

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The combination of two chemically distinct glycosylation reactions, in which one of the leaving groups is activated while the other one remains intact, and vice versa, has led to the discovery of the orthogonal strategy for oligosaccharide synthesis.4... 

O. Kanie, Y. Ito, andT. Ogawa, Orthogonal glycosylation strategy in oligosaccharide synthesis, J. Am. Chem. Soc. 776 12073 (1994). 

H. Paulsen, Progress in oligosaccharide synthesis through a new orthogonal glycosylation strategy,... 

Progress in Oligosaccharide Synthesis through a New Orthogonal Glycosylation Strategy... 

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