Investigations of dehydroepiandrosterone .1. Crystal structure of sublimed DHEA

The crystal structure of an orthorhombic polymorph of the title compound, crystallized by sublimation, has been determined. Dehydroepiandrosterone, C19H28O2, space group P2(1)2(1)2(1) with a = 6.6408(4) b = 11.4423(11) c = 22.085(2)Angstrom, V = 1678.2(4)Angstrom(3), Z = 4. The structure was refined to R = 0.051 for 2645 observed reflections. The conformation of the molecule is similar to that found in other polymorphs and solvates, with a chair A ring, an 8 beta, 9 alpha half-chair B ring, a chair C ring, and a 14 alpha envelope D ring. Molecules are linked in chains by OH ... O hydrogen bonds involving the carbonyl oxygen atom. The O ... O distance is 2.855(3)Angstrom, and the angle about H is 171(2)degrees.