Using CCn1c(-c2nc(Br)cnc2N)nc2cnccc21, OB(O)c1ccccc1 to produce CCn1c(-c2nc(-c3ccccc3)cnc2N)nc2cnccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.