Using Oc1cc(O)c2c(c1)OC(c1ccc(O)c(O)c1)C(O)C2 to produce O=c1cc([C@H]2Oc3cc(O)cc(O)c3C[C@H]2O)cc2c([C@H]3Oc4cc(O)cc(O)c4C[C@@H]3O)cc(O)c(O)c2c1O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.