11 beta-hydroxy-9 beta-estrone.
C18H22O3, Mr = 286.37, trigonal, P3(2), a = 10.091 (1), c = 12.271 (1) A, V = 1082.1 A3, Z = 3, Dx = 1.318 Mg m-3, lambda(Cu K alpha) = 1.5418 A, mu = 0.667 mm-1, T = 298 K, F(000) = 462, final R = 0.056 for 1468 observed reflections. The pattern of intermolecular interaction associated with 11 beta-hydroxy substitution differs from that observed in more potent estrogens.