11β-acetoxy-16α,17α-dimethyl-5β-pregnane-3,20-dione 3,3-dimethyl acetal 、
碘甲烷 以16%的产率得到Isobutyric acid (8S,10R,13S,14S,16R,17S)-10,13,16,17-tetramethyl-3-oxo-17-propionyl-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-11-yl ester