Using ClC(Cl)(Cl)Cl, CC(=O)c1ccc2c(c1)C(=C(O)c1cnccn1)C(=O)N2C(C)=O to produce CC(=O)c1ccc2c(c1)C(=C(Cl)c1cnccn1)C(=O)N2C(C)=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.