Using O=N[O-], O=C(CCl)CC(=O)OCc1ccc([N+](=O)[O-])cc1 to produce O=C(CCl)C(=NO)C(=O)OCc1ccc([N+](=O)[O-])cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.