Using COC(=O)COc1c(-c2ccccc2)c(=O)[nH]c2cc(Cl)ccc12 to produce O=C(O)COc1c(-c2ccccc2)c(=O)[nH]c2cc(Cl)ccc12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.