Using COC(=O)C(OC)c1ccc2nc(-c3ccc(Cl)cc3)oc2c1 to produce COC(C(=O)O)c1ccc2nc(-c3ccc(Cl)cc3)oc2c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.