Using O=C(O)CN1CCN=C(C=Cc2ccc(Cl)c(Cl)c2)c2ccccc21, COCCN to produce COCCNC(=O)CN1CCN=C(C=Cc2ccc(Cl)c(Cl)c2)c2ccccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.