Using COc1cc(OC)nc(OC(Cc2c(Cl)cccc2Cl)C(=O)O)n1, CCBr to produce CCOC(=O)C(Cc1c(Cl)cccc1Cl)Oc1nc(OC)cc(OC)n1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.