Robert John Rafka

Synthesis of 4-seleno-d-fructose derivatives and an investigation of their utility as precursors of unsaturated hexulofuranosides

Abstract 4-Seleno- d -fructose derivatives were prepared by opening of the epoxide ring of methyl 2,3-anhydro-α- and -β- d -tagatofuranosides with phenyl selenide ion. The resulting β-hydroxyselenide system or the corresponding methansulfonate could not be induced to undergo elimination, thus providing the first examples of stable β-methylsulfonyloxyselenides. Oxidation of methyl 1,6-di- O -( tert -butyldimethylsilyl)-3- O -methylsulfonyl-4- Se -phenyl-4-seleno-α- d -fructofuranoside to the corresponding selenoxide, followed by thermally induced syn -elimination of benzeneselenenic acid, provides a convenient route to the novel unsaturated hexulofuranoside, methyl 1,6-di- O -( tert -butyldimethylsilyl)-4-deoxy-β- l - glycero -hex-4-enulofuranoside, which was readily converted into methyl 4-deoxy-α- d - threo -hexulofuranoside.