CRYSTAL-STRUCTURE OF -BETA-PYRROLIDINO-5-PREGNENE-16-ALPHA-CARBONITRILE (HS1175) - A NOVEL DESIGN FOR NEUROMUSCULAR BLOCKING-DRUGS

The structure of the title compound C26H38N2OH has been determined by direct methods from diffractometer data and refined by full-matrix lea st-squares. Crystals are monoclinic P2(1), a = 6.237(1), b = 10.295(2) , c = 18.485(2) angstrom, beta = 98.76(1)degrees, Z = 2, D(c) = 1.12 g cm-3, R = 0.055 for 1059 observed reflections. The structure has two N-containing functional groups, one each in the pyrrolidine ring and c arbonitrile groups, with interatomic separation of 11.527 angstrom. Th e 16-carbonitrile group is alpha-oriented. All steroid rings are trans -connected, A and C being in chair conformations and B and D half-chai rs. N(23) in the carbonitrile side-chair forms a weak tail-tail hydrog en-bond network by linking with the neighboring OH(20) hydroxy group a t 1 - x, 1/2 + y, 1 - z.