Synthesis of azasugars via lanthanide-promoted aza diels-alder reactions in aqueous solution

摘要

Aqueous aza Diels-Alder reactions of chiral aldehydes, prepared from carbohydrates, with benzylamine hydrochloride and cyclopentadiene, were promoted by lanthanide triflates. The exo/ endo selectivities and diastereoselectivities of the reactions were elucidated by NMR, CD spectroscopy, and X-ray crystallography. The nitrogen-containing heterocyclic products were further transformed to azasugars, which are potential inhibitors against glycoprocessing enzymes.