Using Br[Se]c1ccccc1, Cn1ncc([N+](=O)[O-])c1C1=CC(=O)CCCC1 to produce Cn1ncc([N+](=O)[O-])c1C1=CC(=O)C([Se]c2ccccc2)CCC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.