Using COc1ccc2c(c1CN)Oc1c(ccc(OC)c1CC(=O)OCc1ccccc1)C2(C)C to produce COc1ccc2c(c1CN)Oc1c(ccc(OC)c1CC(=O)O)C2(C)C, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.