Koetjapic acid chloro­form hemisolvate

The asymmetric unit of the title compound, C(30)H(46)O(4)·0.5CHCl(3), consists of one koetjapic acid [systematic name: (3R,4aR,4bS,7S,8S,10bS,12aS)-7-(2-carboxy­ethyl)-3,4b,7,10b,12a-penta­methyl-8-(prop-1-en-2-yl)-1,2,3,4,4a,4b,5,6,7,8,9,10,10b,11,12,12a-hexa­deca­hydro­chrysene-3-carboxylic acid] mol­ecule and one half-mol­ecule of chloro­form solvent, which is disordered about a twofold rotation axis. The symmetry-independent component is further disordered over two sites, with occupancies of 0.30 and 0.20. The koetjapic acid contains a fused four-ring system, A/B/C/D. The A/B, B/C and C/D junctions adopt E/trans/cis configurations, respectively. The conformation of ring A is inter­mediate between envelope and half-chair and ring B adopts an envelope conformation whereas rings C and D adopt chair conformations. A weak intra­molecular C—H⋯O hydrogen bond is observed. The koetjapic acid mol­ecules are linked into dimers by two pairs of inter­molecular O—H⋯O hydrogen bonds. The dimers are stacked along the c axis.