Using COC(=O)CCC1(CCC(=O)OC)CCN(C(=O)OC(C)(C)C)CC1 to produce COC(=O)C1CC2(CCC1=O)CCN(C(=O)OC(C)(C)C)CC2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.