[H]OC1=C([H])C(=C(C(=O)O[C@@]2([H])C(=O)[C@]([H])(O[H])[C@@]([H])(O[C@]2([H])OC([H])([H])[H])C([H])([H])[H])C(O[H])=C1[H])C([H])([H])[H]