Using O=C(OC(Cl)(Cl)Cl)OC(Cl)(Cl)Cl, OCC(Nc1nc(-c2ccc(Br)cc2)cs1)C(F)(F)F to produce O=C1OCC(C(F)(F)F)N1c1nc(-c2ccc(Br)cc2)cs1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.