Using COC(=O)c1ccc(OCC2CC(F)(F)CN2C(=O)OC(C)(C)C)cc1 to produce COC(=O)c1ccc(OCC2CC(F)(F)CN2)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.