Using Cc1sc(-c2ccccc2)nc1-c1ccc(Cl)cc1, O=C1CCC(=O)N1Br to produce Clc1ccc(-c2nc(-c3ccccc3)sc2CBr)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.