Using CC(=O)Nc1ccc(Br)cc1[N+](=O)[O-], [N-]=[N+]=[N-] to produce Cc1nnnn1-c1ccc(Br)cc1[N+](=O)[O-], please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.