METHYL (1R,2S,4AR,4BS,7E,8R,8AS,9R,10AR)-2-ACETYLOXY-9-HYDROXY-1,4A,8-TRIMETHYL-7-(2-METHYLAMINOETHOXYCARBONYLMETHYLIDENE)-10-OXO-2,3,4,4B,5,6,8,8A,9,10A-DECAHYDROPHENANTHRENE-1-CARBOXYLATE