Using OB(O)c1cccc(-c2ccccc2)c1, Brc1ccc2cc(Br)ccc2c1 to produce Brc1ccc2cc(-c3cccc(-c4ccccc4)c3)ccc2c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.