MOLECULAR AND CRYSTAL-STRUCTURE OF XY-17-ALPHA-ETHYNYL-5-BETA,6-BETA-EPOXYANDROSTANE, C23H32O4

The crystal structure of a steroid hormone-3 beta-acetoxy-17 beta-hydr oxy-17 alpha-ethynyl-5 beta,6 beta-epoxyandrostane, C23H32O4-is determ ined by X-ray diffraction. The crystals are orthorhombic; a = 14.316(3 ), b = 11.510(2), and c = 12.878(2) Angstrom; V = 2121.9(7) Angstrom(3 ); sp. gr. P2(1)2(1)2(1); Z = 4; and d(calc) = 1.165 g/cm(3). The leas t-squares refinement results in the final R = 0.059 for 1021 unique re flections with I greater than or equal to 3 sigma(1). The specific fea tures of the molecular conformation are discussed. In the unit cell, t he long axes of steroid molecules are extended along the b parameter, and pairs of molecules are hydrogen bonded to form cycles.