STRUCTURE OF THE TRICLINIC MODIFICATION OF 17-BETA-HYDROXY-19-NOR-7 ALPHA-METHYL-17-ALPHA-PREGN-5(10)-EN-20-YN-3-ONE (ORG-OD14)

(I) C21H28O2, M(r) = 312.45, triclinic, P1, a = 6.542 (2), b = 6.6773 (8), c = 10.287 (2) angstrom, alpha = 87.05 (1), beta = 80.09 (2), gamma = 79.17 (2)degrees, V = 434.7 (2) angstrom 3, Z = 1, D(x) = 1.194 g cm-3, lambda(Cu K-alpha) = 1.54184 angstrom, mu = 5.5 cm-1, F(000) = 170, room temperature, R = 0.066 for 1495 reflections with I greater-than-or-equal-to 2.5-sigma(I). The A ring has a 2-alpha,3-beta half-chair conformation, the B ring a 7-alpha,8-beta half-chair conformation. The C ring adopts a slightly distorted chair conformation and the D ring is a distorted 13-beta envelope.