Using COC(=O)c1cc(S(C)(=O)=O)ccc1OCCC(F)(F)F to produce CS(=O)(=O)c1ccc(OCCC(F)(F)F)c(C(=O)O)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.