Using O=[N+]([O-])c1ccc2[nH]nc(Br)c2c1, CC(C)(C)OC(=O)OC(C)(C)C to produce CC(C)(C)OC(=O)n1nc(Br)c2cc([N+](=O)[O-])ccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.