Glycosylations with 2,3-aziridinofuranose derivatives

Two aziridine-containing pentofuranose derivatives were synthesized from d-arabinose and their ability to glycosylate alcohols was explored. The major products are those in which the newly formed glycosidic bond is cis to the aziridine moiety, although in all cases the stereoselectivity is modest. The analogous epoxides have been shown to be more highly stereoselective glycosyl donors. Differences in glycosylation stereoselectivity between the epoxide and aziridine-containing substrates was proposed to arise from steric hindrance between the alcohol acceptor and the nitrogen protecting group in the aziridine substrates.