16α-Hydro­xy-20-oxopregn-5-en-3β-yl acetate

In the title compound, C23H34O4, the two saturated six-membered rings have slightly flattened chair conformations and the unsaturated ring assumes a 8β,9α-half chair conformation distorted towards a 8β-sofa. The five-membered ring has an unusual conformation close to a 13β-envelope. The acetoxy and methyl ketone substituents are twisted with respect to the average molecular plane of the steroid nucleus. The mol­ecules are hydrogen-bonded head-to-head via the hydroxy and methyl ketone groups forming dimers, which are stacked in planes perpendicular to the b axis.