Using O=[N+]=O, COc1c([C@@H](O)CC(C)C)ccc2c1C(=O)OCc1cc(C)cc(O)c1O2 to produce COc1c(C(O)CC(C)C)ccc2c1C(=O)OCc1c(c(O)cc(C)c1[N+](=O)[O-])O2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.