Using COCCl, CCc1cc(S(=O)(=O)Nc2cc(Cl)cnc2Br)ccc1Cl to produce CCc1cc(S(=O)(=O)N(COC)c2cc(Cl)cnc2Br)ccc1Cl, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.