Using [Br-], COC(=O)c1cc2c([nH]1)CCC2CCc1ccccc1 to produce O=C(O)c1[nH]c2c(c1Br)C(CCc1ccccc1)CC2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.