Using COC(=O)CC1C(=O)Nc2ccccc2N1S(=O)(=O)c1ccc(Cl)c(Cl)c1 to produce O=C(O)CC1C(=O)Nc2ccccc2N1S(=O)(=O)c1ccc(Cl)c(Cl)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.