Using CC1(C)CON(Cc2ccc(NC(=O)c3ccccc3C(=O)O)cc2Br)C1=O to produce CC1(C)CON(Cc2ccc(N3C(=O)c4ccccc4C3=O)cc2Br)C1=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.