Using O=C(OO)c1cccc(Cl)c1, CCn1ncc2c(Cl)c3cc(SC)ccc3nc21 to produce CCn1ncc2c(Cl)c3cc(S(C)=O)ccc3nc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.