Using CNc1c(C2=NNC(=O)CC2C)ccc(C(C)=O)c1[N+](=O)[O-] to produce CNc1c(C2=NNC(=O)CC2C)ccc(C(C)=O)c1N, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.