A common access to 2- and 3-substituted methyl β-d-xylopyranosides

2-Deoxy-, 3-deoxy-, 2-deoxy-2-fluoro- and 3-deoxy-3-fluoro- derivatives of methyl β-d-xylopyranoside diacetates were prepared by a new common route via 2,3-anhydropentosides. The stereo- and regioselective introduction of fluorine or hydrogen was accomplished by epoxide ring opening of methyl 2,3-anhydro-β-d-ribopyranoside and methyl 2,3-anhydro-4-O-benzyl-β-d-lyxopyranoside. Methyl 2,3-anhydro-4-O-benzyl-β-d-lyxopyranoside was originally obtained in three simple steps from readily available methyl 2,3-anhydro-4-O-benzyl-β-d-ribopyranoside.