Using CC(=O)N1CCC(N(C(=O)OC(C)(C)C)N(C(=O)OC(C)(C)C)C(=O)c2ccccc2)CC1 to produce CC(=O)N1CCC(N(NC(=O)OC(C)(C)C)C(=O)OC(C)(C)C)CC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.