Using O=[N+]([O-])O, O=C(O)c1cc(-c2ccccc2)cc2c(-c3ccccc3)c(Br)oc12 to produce O=C(O)c1cc(-c2ccccc2)cc2c(-c3ccccc3)c([N+](=O)[O-])oc12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.