A cocrystal of 3α-hy-droxy-tirucalla-8,24-dien-21-oic acid and 3ß-fluoro-tirucalla-7,24-dien-21-oic acid (0.897:0.103).

The title compound, 0.897C(30)H(48)O(3).0.103C(30)H(47)O(2)F is a co-crystal of two triterpenes isolated from the resin of Canarium schweinfurthiiand Engl. Both triterpenes consists of four trans-fused rings having chair/half-chair/half-chair and envelope conformations. The mol-ecular conformations are stabilized by intra-molecular C-H⋯O hydrogen bonds, forming rings of S(7) graph-set motif. In the crystal, mol-ecules are linked by inter-molecular O-H⋯O and C-H⋯O inter-actions, forming sheets parallel to (001). All atoms. excepting the axially-oriented hydroxyl group in the major component and the equatorially-oriented fluorine atom in the minor component, are overlapping.

3α-Hy-droxy-tirucalla-8,24-dien-21-oic acid.

The title compound, C(30)H(48)O(3), a triterpene isolated from the resin of canarium schweinfurthiiand, is an isomer of the previously reported triterpene 3α-hy-droxy-tirucalla-7,24-dien-21-oic acid [Mora et al. (2001 ▶). Acta Cryst. C57, 638-640], which crystallizes in the same trigonal space group. The title mol-ecule consists of four fused rings having chair, half-chair, half-chair and envelope conformations for rings A, B, C and D, respectively (steroid labelling). An intra-molecular C-H⋯O hydrogen bond generates an S(7) ring. In the crystal, mol-ecules are linked by O-H⋯O and C-H⋯O inter-actions, forming (001) sheets.