Crystal and molecular structure of 17β-hydroxy-17α-methyl-2-oxa-5α-androstan-3-one

Abstract

Crystals of the title compound (I) are monoclinic, a= 9.146(3), b= 9.591(3), c= 9.512(4)Å, β= 91.38(4)° space group P21, Z= 2. The structure was determined from diffractometer data by direct methods, and refined by full-matrix least-squares methods to R 0.035 for 1 429 observed reflexions. Ring A may be described as having either a slightly distorted half-chair conformation with a non-planar lactone group, or as having a flattened chair conformation. Rings B and C have regular chair, and ring D a C(13) envelope conformation. The molecules are linked by O–H ⋯ O hydrogen bonds (2.893 Å) and form infinite chains within layers perpendicular to the a axis. There are no short intermolecular contacts between layers.