[H]C([H])=C([H])[C@@]1(C([H])=C2C([H])([H])C([H])([H])[C@@]3([H])[C@](C([H])([H])[H])(C([H])([H])OC([H])=O)C([H])([H])C([H])([H])C([H])([H])[C@]3(C([H])([H])[H])[C@@]2([H])C([H])([H])C1([H])[H])C([H])([H])[H]