title: 17α-Ethynyl-3-methoxy-estra-1,3,5(10),9(11)-tetraen-17-ol.
abstract: In the title compound, C(21)H(24)O(2), rings B, C and D adopt half-chair, distorted half-chair and envelope conformations, respectively. In the crystal structure, there is an inter-molecular O-H⋯O hydrogen bond. The mol-ecules are arranged in a head-to-tail fashion, with the meth-oxy and hydr-oxy groups forming a two-dimensional hydrogen-bond network.
authors.forename: Hongqi
authors.initials: H
authors.lastname: Li
authors.forename: Yanxi
authors.initials: Y
authors.lastname: Song
authors.forename: Fengyan
authors.initials: F
authors.lastname: Ge