Using CCOC(=O)c1cn(-c2ccc(F)cc2F)c2cc(Cl)c(F)cc2c1=O to produce O=C(O)c1cn(-c2ccc(F)cc2F)c2cc(Cl)c(F)cc2c1=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.