3α-Hydroxytirucalla-8,24-dien-21-oic acid

The title compound, C30H48O3, a triterpene isolated from the resin of canarium schweinfurthiiand, is an isomer of the previously reported triterpene 3α-hydroxytirucalla-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 molecule 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 intramolecular C—H...O hydrogen bond generates an S(7) ring. In the crystal, molecules are linked by O—H...O and C—H...O interactions, forming (001) sheets.