Using CCOC(=O)COc1cc2c(c(Cl)c1Cl)C(=O)C(C)(C(C)C)C2, O=C1CCC(=O)N1Br to produce CCOC(=O)COc1cc2c(c(Cl)c1Cl)C(=O)C(C)(C(C)C)C2Br, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.