Using Nc1cnc2c(n1)CCNCC2, O=C(Cl)Cc1ccc(Cl)cc1 to produce Nc1cnc2c(n1)CCN(C(=O)Cc1ccc(Cl)cc1)CC2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.