Using CC(C)(C)OC(=O)N1CC(=O)C1, CC[N+](=O)[O-] to produce CC([N+](=O)[O-])C1(O)CN(C(=O)OC(C)(C)C)C1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.