Using CCCC(CC(=O)O)n1c(=O)n(Cc2cc(Br)cc3c2N(C)C(=O)C3(Br)Br)c2ccccc21 to produce CCCC(CC(=O)O)n1c(=O)n(Cc2cc(Br)cc3c2N(C)C(=O)C3)c2ccccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.