Glycoprocessing

Aqueous aza-Diels-Alder reactions of chiral aldehydes, prepared from carbohydrates and with benzylamine hydrochloride and cyclopentadiene, were promoted by lanthanide triflates (Eq. 12.65).137 The nitrogen-containing heterocyclic products were further transformed into aza sugars, which are potential inhibitors against glycoprocessing enzymes. 

Structural relationships suggest that the extended carbohydrate scaffolds obtainable by such tandem aldolizations may be regarded as metabolically stable mimetics of oligosaccharides, in particular of C-glycosides that are hydrolytically stable. The latter class of compounds shares an interest for potential therapeutic applications with the class of so-called aza sugars that have commanded attention in recent years as potent glycoprocessing inhibitors for the treatment of diabetes and other metabolic disorders, as well as for the blocking of viral or microbial infection and metastasis. 

G. C. Look, C. H. Fotsch, and C.-H. Wong, Enzyme-catalyzed organic synthesis Practical routes to aza sugars and their analogs for use as glycoprocessing inhibitors, Acc. Chem. Res. 26 182(1993). 

The purpose of this chapter is to provide an overview of the application of monosaccharides for the synthesis of novel compounds, and in particular we have focused on bioactive compounds that target protein-protein or peptide-protein interactions. We have not reviewed extensively the application of monosaccharides as scaffolds that modulate carbohydrate-protein interactions (glycomimetics or inhibitors of glycoprocessing enzymes) as these are considered elsewhere. Also it has not been possible to detail all of the work of those groups who have contributed to this area. The review is divided into two main sections synthesis and application of monosaccharides that are SAAs and synthesis and application of monosaccharides that are not SAAs. The structures and applications of the monosaccharide building blocks are considered as are the synthesis and properties of target compounds. 

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