(1R,2R,3R,4S,5S)-3-Methyl-8-oxa­bicyclo­[3.2.1]oct-6-ene-2,4-diyl diacetate

The mol­ecule of the title compound, C12H16O5, has crystallographically imposed mirror symmetry with the mirror plane passing through the endocyclic O atom and the mid-point of the double bond. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds, forming chains running along the a axis

3-exo-Chloro-8-oxabicyclo­[3.2.1]oct-6-ene-2,4-diol chloro­form 0.33-solvate

The title compound, 3C7H9ClO3·CHCl3, crystallizes with mol­ecules of 3-exo-chloro-8-oxabicyclo­[3.2.1]oct-6-ene-2,4-diol (A) and chloro­form in a 3:1 ratio, in the space group R3m. Mol­ecules of A straddle a crystallographic mirror plane, whereas the chloro­form mol­ecules (C and H atoms) lie additionally on the threefold axis. The mol­ecules of A are linked into right- and left-helical chains by means of O—H⋯O hydrogen bonds, thus forming columns running along the c axis. Six inter­penetrated columns form a channel in which the solvent mol­ecules (chloro­form) are located