[H]C([H])=C1[C@]2([H])[C@]3([H])[C@]([H])(C([H])([H])[C@@]1([H])OC(=O)C([H])([H])[H])[C@@]2(C([H])([H])[H])C([H])([H])C([H])([H])C([H])([H])C3(C([H])([H])[H])C([H])([H])[H]