Using Cc1onc(-c2ccccc2)c1-c1ccnc(Br)c1, O=C1CCC(=O)N1Br to produce BrCc1onc(-c2ccccc2)c1-c1ccnc(Br)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.