Brasilixanthone

The title xanthone [systematic name: 5,13-dihy­droxy-3,3,10,10-tetra­methyl-3H-dipyrano[3,2-a:2′,3′-i]xanthen-14(10H)-one], C(23)H(20)O(6), was isolated from the roots of Cratoxylum formosum ssp. pruniflorum. There are two mol­ecules (A and B) in the asymmetric unit, which show chemical but not crystallographic inversion symmetry. The xanthone skeleton in both mol­ecules is approximately planar, with an r.m.s. deviation of 0.0326 (9) Å for mol­ecule A and 0.0355 (9) Å for mol­ecule B from the plane through the 14 non-H atoms. The pyran rings in both mol­ecules adopt sofa conformations. Intra­molecular O—H⋯O hydrogen bonds generate S(5) and S(6) ring motifs. Viewed onto the bc plane, the crystal structure resembles a herringbone pattern. Stacks of mol­ecules are stabilized by π–π inter­actions with centroid–centroid distances of 3.600 (5) Å. The crystal structure is further stabilized by weak C—H⋯O and C—H⋯π inter­actions.