Crystallographic investigations of 3 beta-acetoxy-5 alpha-cholestan-6-one-semicarbazone - A steroid

The crystal structure of 3 beta -acetoxy-5 alpha -cholestan-6-one-semicarba zone (C30H51O3 N-3) has been determined by X-ray diffraction methods. It cr ystallizes in the orthorhonibic space group P2,2,2, with cell parameters a = 11.641(l), b = 16.552(1) c 31.181(4) Angstrom and Z = 8. The structure ha s been refined to an R-value of 0.050 for 4407 observed reflections. Two mo lecules in the asymmetric unit have been observed. In both the crystallogra phically independent molecules, all the three six-membered rings (A, B and C) of steroid nucleus exist in chair conformation, while the five- membered ring D exists in 13 beta distorted-envelope in molecule-I and 13 beta, 14 alpha half-chair conformation in molecule-II. Three intermolecular N-H...O hydrogen bonds have been observed.