Using CC(C)(C)OC(=O)CC(=O)OC(C)(C)C, O=[N+]([O-])c1ccc(F)c(F)c1Oc1cc(Cl)cc(Br)c1 to produce CC(C)(C)OC(=O)C(C(=O)OC(C)(C)C)c1ccc([N+](=O)[O-])c(Oc2cc(Cl)cc(Br)c2)c1F, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.