Using COCC1(CBr)COC1, COc1ccc(-c2cccc3c2CCC3=O)c(OC)c1O to produce COCC1(COc2c(OC)ccc(-c3cccc4c3CCC4=O)c2OC)COC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.