Using O=c1n(-c2cc(O)c(Cl)cc2Cl)nc2n1CCCC2, ClCCBr to produce O=c1n(-c2cc(OCCCl)c(Cl)cc2Cl)nc2n1CCCC2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.