A facile and quantitative preparation of activated cyclic sugar derivatives using HgBr2 and 2,4,6-collidine

Article abstract of DOI:10.1246/bcsj.68.1715

A combination of mercury(II) bromide (HgBr₂) and 2,4,6-collidine was found to promote the formation of activated cyclic sugar derivatives such as 1,2-orthoesters and an oxazoline derivative in quantitative yields at room temperature. A slightly hindered skew like conformation of the lactose orthoester derivative was revealed by ¹H NMR analysis. It was also suggested that the reaction of a lactose 1,2-orthoester with trimethylsilyl azide proceeded smoothly to give β-lactosyl azide stereoselectively which is a useful intermediate for constructing glycopeptides and neoglycoconjugates.