最佳答案
O=C1C([H])([H])C([H])([H])[C@@]2(C([H])([H])[H])[C@]([H])(C1(C([H])([H])[H])C([H])([H])[H])C([H])([H])C([H])([H])[C@]1(C([H])([H])[H])[C@]2([H])C([H])([H])C([H])([H])[C@]2([H])[C@@]3([H])[C@]([H])(C(=C([H])[H])C([H])([H])[H])C([H])([H])C([H])([H])[C@]3(C([H])([H])[H])C([H])([H])C([H])([H])[C@@]12C([H])([H])[H]
