Using Cc1nc2sccc2c(=O)n1-c1ccccc1Cl, O=C1CCC(=O)N1Br to produce Cc1nc2sc(Br)cc2c(=O)n1-c1ccccc1Cl, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.