Using COC(=O)c1c(C)c([N+](=O)[O-])cc2[nH]c(=O)c(=O)[nH]c12 to produce Cc1c([N+](=O)[O-])cc2[nH]c(=O)c(=O)[nH]c2c1C(=O)O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.