Using CC(O)c1cc(Cl)cc(-c2ccc(C#N)cc2)c1, BrC(Br)(Br)Br to produce CC(Br)c1cc(Cl)cc(-c2ccc(C#N)cc2)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.