Using ClCCBr, COc1cc2c(Oc3ccc(NC(=O)NCCC(C)(C)C)c(F)c3)ccnc2cc1O to produce COc1cc2c(Oc3ccc(NC(=O)NCCC(C)(C)C)c(F)c3)ccnc2cc1OCCCl, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.