['CN', 'CCCCCC(C)Nc1ccc(C=O)cc1[N+](=O)[O-]', 'CCCCCCC', 'CNC(=O)c1ccc(N)c([N+](=O)[O-])c1', 'CCCCCC(C)N', 'CNC(=O)c1cccc([N+](=O)[O-])c1', 'CNC=O', 'CCCCCC(C)Nc1ccccc1[N+](=O)[O-]']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.