Using O=C1Nc2c(ccc3ccccc23)SC1c1ccc(Cl)cc1, ClCCCBr to produce O=C1C(c2ccc(Cl)cc2)Sc2ccc3ccccc3c2N1CCCCl, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.