Using O=C1CCC(=O)N1Br, COC(=O)Cc1ccc([N+](=O)[O-])cc1 to produce COC(=O)C(Br)c1ccc([N+](=O)[O-])cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.