The title compound, C(26)H(34)O(11), known as bruceine A, is a natural quassinoid extracted from the dried fruits of Brucea javanica. Its structure consists of five fused rings including an oxygen-containing heterocyclic ring and a lactone ring. Two intra-molecular O-H⋯O links help to establish the mol-ecular conformation. In the crystal, O-H⋯O hydrogen bonds connect the mol-ecules.