Using C=C1C[C@@H]2CN(C(=O)OCc3ccccc3)C[C@]2(NC(=O)OC(C)(C)C)C1, C=[N+]=[N-] to produce CC(C)(C)OC(=O)N[C@]12CN(C(=O)OCc3ccccc3)C[C@H]1CC1(CC1)C2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.