Using COC(=O)CC(C(=O)c1ccc2nc(-c3ccccc3)oc2c1)C(C)C to produce CC(C)C(CC(=O)O)C(=O)c1ccc2nc(-c3ccccc3)oc2c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.