The crystal structure of 3,4,6,1',3'4'-hexa-O-acetyl-α-D-fructofuranose-β-D-fructofuranose 1,2':2,6'-dianhydride, 1, has been determined. The central, eight-membered 1,3,6-trioxacane ring is in a twist-boat-chair conformation. Molecular modeling has shown that this conformation is inherent and not due to crystal packing forces and is also the most likely conformation present in underivatized α-D-fructofuranose-β-D-fructofuranose 1,2':2,6'-dianhydride.