6,17α-Dimethyl-4,6-pregnadiene-3,20-dione (medrogestone, 2) is for a long time known steroid endowed with progestational activity. In order to study its crystallographic and NMR spectroscopic properties with the aim to fill the literature gap, we prepared medrogestone following a traditional procedure. A careful NMR study allowed the complete assignment of the 1H and 13C NMR signals not only of medrogestone but also of its synthetic intermediates. The structural and stereochemical characterizations of medrogestone together with its precursor 17α-methyl-3-ethoxy-pregna-3,5-dien-20-one were described by means of X-ray analysis, allowing a deepened conformational investigation.Graphical abstract
Conformational and stereochemical characterization of 6,17α-dimethyl pregnan-4,6-dien-3-one (medrogestone, red) and its precursor 17α-methyl-3-ethoxy-pregna-3,5-dien-20-one (green) by means of X-ray and NMR analysis.