Using CCOC(=O)C[C@H](Cc1cc(Br)c2[nH]nc(Cl)c2c1COC(C)=O)C(=O)OCC to produce COC(=O)C[C@H](Cc1cc(Br)c2[nH]nc(Cl)c2c1CO)C(=O)OC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.