Using Oc1ccc(C2Cc3c(CBr)cc(O)cc3C3CCCC23)cc1, CO to produce COCc1cc(O)cc2c1CC(c1ccc(O)cc1)C1CCCC21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.