Large-Scale Synthesis of 2,3,4,6-Tetra-O-benzyl-1-deoxynojirimycin

Since their isolation in the 1960s, imino sugars have attracted considerable interest from synthetic chemists, biologists, and clinical researchers. ¹ Glycomimetics in which the endocyclic oxygen of the parent glycoside is replaced by a nitrogen atom are known to be potent inhibitors of a number of enzymes of medicinal interest, such as glycosidases, ² glycosyltransferases, ³ and, most recently, enzymes that act on non-sugar substrates. ⁴ In the glycomimetics world, 1-deoxynojirimycin (DNJ) may be considered as the “king” of imino sugars (Figure 36.1). Indeed, since its first synthesis, ⁵ more than one thousand derivatives of DNJ have been reported in the literature, most of them being evaluated towards relevant biological targets. ^1,2 It is thus not surprising that the two imino sugar drugs currently on the market are based on the DNJ motif (Figure 36.1).