Using CC(C)(C)OC(=O)NC1(C(=O)NCc2ccc(Cl)cc2)CCN(C(=O)OC(C)(C)C)CC1 to produce NC1(C(=O)NCc2ccc(Cl)cc2)CCNCC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.