Using O=C(OCc1ccccc1)N1CCN(c2ccc(N3CCC4(CC3)OCCO4)cc2)CC1 to produce O=C1CCN(c2ccc(N3CCN(C(=O)OCc4ccccc4)CC3)cc2)CC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.