Structure reassignment of a steroid refuting the isolation of rotational isomers around the C(17)–(20) bond. X-Ray crystal and molecular structure of 3β-acetoxy-17aα-(2-acetoxyethoxy)-17α,17aβ-dimethyl-D-homoandrost-5-en-17β-o1

Abstract

The previously assigned structure of 20-methyl-20β-(2-hydroxyethoxy)pregn-5-ene-3β,17α-diol diacetate is reassigned, on the basis of an X-ray crystal structure analysis, to be 3β-acetoxy-17aα-(2-acetoxyethoxy)-17α,17aβ-dimethyl-D-homoandrost-5-en-17β-ol, thus disproving the isolation of the C-20 steroidal stereoisomers with asymmetry due to restricted rotation about the C(17)–(20) bond.