Using Nc1nccc(CO)n1, O=[N+]([O-])c1ccc(O)c2ccccc12 to produce Nc1nccc(COc2ccc([N+](=O)[O-])c3ccccc23)n1, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.