Using CCOCn1c(-c2ccc(Cl)cc2)c(C(=O)OC)c(Br)c1C(F)(F)F to produce CCOCn1c(-c2ccc(Cl)cc2)c(C(=O)O)c(Br)c1C(F)(F)F, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.