6,8-Dioxabicyclo[3''2[image]1]octane (2), obtained from acid-catalyzed cyclization of the NaBH4 reduction product of acrolein dimer, was converted to 4-bromo-6,8-dioxabicyclo[3[image]2[image]1]octane 3. Epoxidation of the base-catalyzed dehydrohalogenated product of 3,6,8-dioxabicyclo [3[image]2[image]1]oct-3-ene (4), gave stereoselectively 1,6:2,3-dianhydro-4-deoxy-[beta]-DL-ribo-hexopyranose (5) contaminated with < 5% of the isomeric 1,6;2,3-dianhydro-4-deoxy-[beta]-DL-lyxo-hexopyranose (6) Compound 5, with the contaminating 6, subjected to treatment with aqueous KCH, gave 1,6-anhydro-4-deoxy-[beta]-DL-xylo-hexopyranose whose di-p-nitro-benzoate gave a 100 MHz nuclear magnetic resonance (n.m.r.) spectrum superimposable on that obtained from an authentic sample of 1,6-anhydro-4-deoxy-[beta]-D-xylo-hexopyranose di-p-nitrobenzoate. A 1st order analysis of the n.m.r. spectrum of 5 showed that the anomeric proton was coupled to all other protons except H-4 exo. Long range coupling over 5 bonds, as well as over 4 bonds, is observed. Couplings between H-1 and H-6 or H-5 illustrate that such effects can be obtained when an O2 atom replaces C as in the structural feature [image].