Steroids 35: synthesis of 16,16-dimethyl-17 beta-hydroxysteroids.
The reaction of 16-methylene-17-ketosteroids (Ia), (Ic) and (Ie) with methyl magnesium iodide yields 16-methylene-17 alpha-methyl-17 beta-hydroxysteroids (IIa), (IIb) and (IId). These are subjected to the addition of hypobromous acid and the subsequent anionotropic rearrangement to convert them into 16 alpha-methyl-16 beta-bromomethyl-17-ketosteroids (Va), (Vb) and (Vd). These were reduced with LiA1H4 to obtain 16,16-dimethyl-17 beta-hydroxysteroids (VIa), (VIb) and (VId). Compounds (VIIa) and (VIIe) were selectively deacetylated yielding (VIIb) and (VIId); these were then oxidized and hydrolyzed to convert them into (VIf) and (VIg).
Schneider
G
G
Department of Organic Chemistry, Jozsef Attila University, Szeged, Hungary.
Wolfling
J
J
Mesko
E
E
Dombi
G
G
D055598:Chemical Phenomena; D002621:Chemistry; D006914:Hydroxysteroids / Q000138:chemical synthesis*
D006914:Hydroxysteroids