Using COC(=O)C1(NC(=O)CCCCl)CCN(C(=O)OC(C)(C)C)CC1 to produce COC(=O)C1(N2CCCC2=O)CCN(C(=O)OC(C)(C)C)CC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.