Using COC(=O)c1ccc(Cc2nc(-c3ccc(Cl)c(Cl)c3)cs2)cc1 to produce O=C(O)c1ccc(Cc2nc(-c3ccc(Cl)c(Cl)c3)cs2)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.