1,2:5,6-Di-O-iso-propyl-idene-3-C-methyl-α-d-allo-furan-ose.

The title carbohydrate, C13H22O6, is a derivative of d-glycose, in which the furan-osidic and iso-propyl-idene rings are in twisted conformations. The mean plane of the furan-osidic ring makes a dihedral angle of 70.32 (18)° with the mean plane of the fused iso-propyl-idene ring. The methyl groups in the other iso-propyl-idene ring are disordered over two sets of sites, with an occupancy ratio of 0.74 (6):0.26 (6). In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds into chains with graph-set notation C(5) along [100]. Weak C-H⋯O interactions also occur.