Stereoselective synthesis of various α-selenoglycosides using in situ production of α-selenolate anion

A large variety of α-selenoglycosides, including alkyl and aryl selenoglycosides, selenoglycosyl amino acid and selenodisaccharide have been synthesized in a stereoselective manner. The key precursor of α-anomeric selenolate anion was designed as p-methylbenzoyl selenoglycoside, which was synthesized by the reaction of β-glycosyl chloride with potassium p-methylselenobenzoate. Upon the action of piperazine or methylhydrazine in the presence of Cs2CO3, the acyl selenoglycoside produced an anomeric selenolate anion, which reacted in situ with various electrophilic counterparts to yield α-selenoglycoside.