Using ClCCCBr, CCOC(=O)c1ccc2oc(-c3ccccc3)c(O)c(=O)c2c1 to produce CCOC(=O)c1ccc2oc(-c3ccccc3)c(OCCCCl)c(=O)c2c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.