Using COCc1c(C(=O)OC(C)C)ncc2[nH]c3cccc(Oc4ccc(Cl)cc4)c3c12 to produce COCc1c(C(=O)OC(C)C)ncc2[nH]c3cccc(Oc4ccccc4)c3c12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.