Using Fc1ccccc1S, CC(=O)Nc1cn2nc(-c3ccnc(F)c3)ccc2n1 to produce CC(=O)Nc1cn2nc(-c3ccnc(Sc4ccccc4F)c3)ccc2n1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.