In the title compound, C20H16O4, the cyclohexene ring adopts a twisted
-boat conformation. The molecule contains an enol sub-unit and the hyd
roxyl group forms an intramolecular hydrogen bond to the cyclic carbon
yl group, with an O O distance of 2.485(3) Angstrom and an O-H ... O a
ngle of 148 (3)degrees. Enantiomeric pairs of molecules form centrosym
metric dimers by mutual hydrogen bonding of carboxyl groups, with O ..
. O distances of 2.649 (3) Angstrom.