Using COC(=O)CC(=O)OC, CCc1cc2c(C(=O)C(C)Br)cc(F)cn2n1 to produce CCc1cc2c(C(=O)C(C)C(C(=O)OC)C(=O)OC)cc(F)cn2n1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.