Using CC1(C)C=Cc2c(O)c(C=O)cc([N+](=O)[O-])c2O1, O=C([O-])[O-] to produce COc1c(C=O)cc([N+](=O)[O-])c2c1C=CC(C)(C)O2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.