Using COC(=O)C1(CN2CCC(CNC(=O)OC(C)(C)C)CC2)CCOCC1 to produce CC(C)(C)OC(=O)NCC1CCN(CC2(C(=O)O)CCOCC2)CC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.