Using O=S(Cl)Cl, COC(=O)C(CF)(CC(=O)O)N1C(=O)c2ccccc2C1=O to produce COC(=O)C(CF)(CC(=O)Cl)N1C(=O)c2ccccc2C1=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.