Using COc1cc(CBr)c(-c2c(CBr)cc(OC)cc2OC)c(OC)c1 to produce Oc1cc(O)c(-c2c(O)cc(O)cc2CBr)c(CBr)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.