Using COC(=O)C12CC3CC(C1)C(NC(=O)N1CCOc4ccccc41)C(C3)C2 to produce O=C(NC1C2CC3CC1CC(C(=O)O)(C3)C2)N1CCOc2ccccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.