Synthesis of erythro and threo furanoid glycals from 1- and 2-phenylselenenyl–carbohydrate derivatives Original Research Article

Differently protected erythro and threo furanoid glycals were synthesized by selenoxide elimination when phenyl 1-selenoglycosides were treated in oxidizing conditions (tBuOOH, Ti(OiPr)4, Et2iPrN). The phenyl 1-selenoglycosides were obtained from methyl 2-deoxy-d-erythro-pentofuranoside by protection of the primary hydroxyl or both hydroxyls and further reaction with PhSeH in the presence of BF3·Et2O. Erythro and threo furanoid glycals were also prepared by treating 2-deoxy-2-phenylselenenyl-1,4-anhydrocyclitols under similar conditions. The 2-deoxy-2-phenylselenenyl-1,4-anhydrocyclitols were obtained from 4-pentene-1,2,3-triols by a 5-endo selenium electrophilic induced cyclization.