CCOC(=O)[C@]1(O)C[C@@]2(C)C(=CC[C@H]3[C@@H]4CC[C@H]([C@H](C)CCCC(C)C)[C@@]4(C)CC[C@@H]32)C1=O ethyl (2S,3aR,3bS,5aR,6R,8aS,8bS)-2-hydroxy-3a,5a-dimethyl-6-[(2R)-6-methylheptan-2-yl]-1-oxo-3,3b,4,5,6,7,8,8a,8b,9-decahydroindeno[5,4-e]indene-2-carboxylate