Using O=C([O-])[O-], CCOC(=O)c1cn2c(=O)[nH]c3ccccc3n2c1=O to produce CCOC(=O)c1cn2c(=O)n(C)c3ccccc3n2c1=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.