Lewis structure, oligosaccharides

Based on die highly developed art of oligosaccharide synthesis, orgamc-chemical, enzyme-catalyzed, and combined organic-enzyme-catalyzed syntheses of the Sialyl-Lewis structure and related oligosaccharides have been devised. Selected examples of these syntheses are discussed in Section IV, some of them including recently developed procedures of glycoside formation. 

The precise chemical nature of some of the ligands involved in selectin-ligand interactions has been determined. All three selectins bind sialylated and fucosy-lated oligosaccharides, and in particular all three bind sialyl-Lewis (Figure 47-12), a structure present on both glycoproteins and glycolipids. Whether this compound is the actual ligand involved in vivo is not estab-... 

Groups XXXVIII. Structures and Activities of Oligosaccharides Produced by Alkaline Degradation of Blood Group Lewis Substance. Proposed structure of the Carbohydrate Chains of Human Blood Group A, B, H, Lea, and Leb Substances, Biochemistry (1968) 7, 2976. 

An associated enzyme, al-3-fucosyltransferase, has also been used in syntheses to provide the Lewis x and sialyl Lewis x structural motifs [65]. Increasing availability of fucosyltransferases via cloning techniques are expected to have a strong influence on oligosaccharide synthesis in the near future. 

H. Tanaka, N. Matoba, H. Tsukamoto, H. Takimoto, H. Yamada, and T. Takahashi, Automated parallel synthesis of a protected oligosaccharide library based upon the structure of dimeric Lewis X by one-pot sequential glycosylation, SYNLETT, (2005) 824—828. 

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