Using CC(C)(C)OC(=O)N1CCN2C(=O)N(c3cc(Cl)cc(Cl)c3)C(=O)C2C1 to produce O=C1C2CNCCN2C(=O)N1c1cc(Cl)cc(Cl)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.