[1a(1a alpha,5 beta,9a alpha)]-1,1a,4,5,7,8,9,9a-Octahydro-3-hydroxy-1,1,2,5-tetra-methyl-7-methylene-6H-cyclopropa-[3,4]cyclohept[1,2-e]inden-6-one

Interest in the title structure, C20H24O2, lies in the novel cis ring junct ion between the three- and seven-membered rings. This stereochemical arrang ement causes the methylene moiety and the cycloheptane ring to be twisted o ut of the plane of the aromatic ring. The cyclopropane ring is also twisted out of the plane of the aromatic system. The molecules are linked by an O- H ... O hydrogen bond [O ... O 2.741 (3) Angstrom].