(8S,9S,10R,11S,13S,14S,16R,17S)-17-(2-((tert-Butyldimethylsilyl)oxy)acetyl)-11,17-dihydroxy-10,13-dimethyl-3-oxo-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-16-yl Butyrate