[H]OC1=C(C2=C(C(=O)O[C@]([H])(C([H])([H])[H])[C@@]2([H])C([H])([H])[H])C(OC2=C(O[H])C(O[H])=C(C3=C2O[C@]([H])(C([H])([H])[H])[C@@]3([H])C([H])([H])[H])C([H])([H])[H])=C1[H])C([H])([H])[H]