Using COC(=O)c1ccc(COc2ccc(C(=O)c3ccccc3)cc2)o1 to produce COC(=O)c1ccc(COc2ccc(C(O)c3ccccc3)cc2)o1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.