Using FC(F)(Br)C(F)(F)Br, Cc1cn2nc(C)c(NC(=O)OC(C)(C)C)c2s1 to produce Cc1nn2c(Br)c(C)sc2c1NC(=O)OC(C)(C)C, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.