Using COc1ccc2sc3c([N+](=O)[O-])ccc(Cl)c3c(=O)c2c1 to produce O=c1c2cc(O)ccc2sc2c([N+](=O)[O-])ccc(Cl)c12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.