Using CCCC[Sn](Cl)(CCCC)CCCC, FC(F)(F)Sc1ncn2ccsc12 to produce CCCC[Sn](CCCC)(CCCC)c1cn2cnc(SC(F)(F)F)c2s1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.