4a-Hydroxy-9-(4-hydroxyphenyl)-4,4a,5,6,9,9a-hexahydro-3H-xanthene-1,8(2H,7H)-dione

The title compound, C(19)H(20)O(5), was synthesized by the reaction of 1,3-cyclo­hexa­nedione and 4-hy­droxy­benzaldehyde in the presence of PdCl(2) and thio­urea. The tetra­hydro­pyran ring and the six-membered cyclo­hexene ring adopt envelope conformations, and the six-membered cyclo­hexane ring is in a chair conformation. The crystal packing is stabilized by classical inter­molecular O—H⋯O hydrogen bonds and weak C—H⋯O inter­actions.