['CC1CC1', 'O=Cc1ccc(O)c([N+](=O)[O-])c1', 'OCC1CC1', 'O=Cc1cccc([N+](=O)[O-])c1', 'C1CC1', 'COc1ccc(C=O)cc1[N+](=O)[O-]']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc(OCC2CC2)cc1.