Using CCOC(=O)C(C(=O)OCC)C(c1ccccc1)c1c[nH]c2ccncc12 to produce O=C(O)C(C(=O)O)C(c1ccccc1)c1c[nH]c2ccncc12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.