Using COCOc1cc(OC)c(OCOC)c(CCCCOS(C)(=O)=O)c1OC, [I-] to produce COCOc1cc(OC)c(OCOC)c(CCCCI)c1OC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.