Using BrC(Br)(Br)Br, O=C(Nc1ccc(Oc2ccc(CCCO)cc2)c(F)c1)c1ccc(Cl)c(Cl)c1 to produce O=C(Nc1ccc(Oc2ccc(CCCBr)cc2)c(F)c1)c1ccc(Cl)c(Cl)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.