C21H30O4 (295 K): monoclinic space P21, a = 5.877(1), b = 14.801(1), c = 10.893(2) Å, β = 104.78(1)̃, V = 916.2(2) Å3, D3 = 1.256 g - cm-3, Z = 2, F(000) = 376, λ(CuKα) = 1.5418 Å, μ = 0.682 mm-1. The title compound was isolated as a further fraction from the powder of Ecdysanthera rosea Hook, et Arn. (Apocynaceae) of Vietnam, and its structure wes elucidated. It was found that it is a pentacyclic steroidal moleclue with 3 six-membered and 2 five-membered rings with the six/five and the five/five membered ring fusions beeing cis in both cases. Two intermolecular OH... O hydrogen bonds generate a two-dimensional network, where four molecules contribute to a cyclic hydrogen bond pattern.
