Using O=C1CCC(=O)N1Br, Cc1cc([N+](=O)[O-])ccc1C(F)(F)C(F)(F)F to produce O=[N+]([O-])c1ccc(C(F)(F)C(F)(F)F)c(CBr)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.