methyl (1R,4aR,4bS,10aR)-1,4a-dimethyl-7-propan-2-ylidene-3,4,4b,5,6,9,10,10a-octahydro-2H-phenanthrene-1-carboxylate;methyl (1R,4aR,4bS,10aR)-7-isopropylidene-1,4a-dimethyl-3,4,4b,5,6,9,10,10a-octahydro-2H-phenanthrene-1-carboxylate;(1R,4aR,4bS,10aR)-7-isopropylidene-1,4a-dimethyl-3,4,4b,5,6,9,10,10a-octahydro-2H-phenanthrene-1-carboxylic acid methyl ester
methyl (1R,4aR,4bS,10aR)-1,4a-dimethyl-7-propan-2-ylidene-3,4,4b,5,6,9,10,10a-octahydro-2H-phenanthrene-1-carboxylate