Using O=[N+]([O-])O, CC(=O)C12CC3CC1CC(c1ccccc1)(C3)C2 to produce CC(=O)C12CC3CC1CC(c1ccc([N+](=O)[O-])cc1)(C3)C2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.