Using BrC(Br)(Br)Br, CC(CCO)C(=O)NN=C(c1ccccc1)c1ccccc1 to produce CC(CCBr)C(=O)NN=C(c1ccccc1)c1ccccc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.