3-[(3S,5S,10R,13R,14S,17R)-5,14-dihydroxy-3-[(2R,5R)-5-hydroxy-4-methoxy-6-methyloxan-2-yl]oxy-10,13-dimethyl-2,3,4,6,7,8,9,11,12,15,16,17-dodecahydro-1H-cyclopenta[a]phenanthren-17-yl]-2H-furan-5-one