Using O=[N+]([O-])c1ccc(O)cc1, CC(C)[C@H](NC(=O)[C@H](C)N)C(=O)N[C@@H](C)C(=O)O to produce CC(C)[C@H](NC(=O)[C@H](C)N)C(=O)N[C@@H](C)C(=O)Oc1ccc([N+](=O)[O-])cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.