7-Hy­droxy-8-isopropyl-1,1,4a-trimethyl-4a,9,10,10a-tetra­hydro-phenanthren-2(1H)-one

The title compound, C(20)H(26)O(2), was isolated from a chloro­form extract of Tetra­clinis articulata wood. The mol­ecule contains three fused rings which exhibit different conformations. The non-aromatic oxo-substituted ring has a screw-boat conformation, while the central ring has a half-chair conformation. In the crystal, mol­ecules are linked to each other by inter­molecular O—H⋯O hydrogen bonds involving the carbonyl and hy­droxy groups.