Crystal structure and Hirshfeld surface analysis of 3-oxours-12-ene-27a,28-dioic acid (quafrinoic acid)

The title compound, C(30)H(44)O(5), is a penta­cyclic triterpene isolated from the Cameroonian medicinal plant Nauclea Pobeguinii and known as quafrinoic acid. The mol­ecule is composed of five fused six-membered rings, four of which adopt a chair conformation and one a half-chair conformation. Intra­molecular C—H⋯O hydrogen-bond inter­actions exist, which generate S6 and S8 rings. In the crystal, mol­ecules are linked by pairs of O—H⋯O hydrogen bonds, linking R (2) (2)(8) rings into chains running parallel to the a axis; these chains are further connected into layers parallel to the ab plane by C—H⋯O hydrogen bonds. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (79.4%) and O⋯H (20.4%) inter­actions.