['COc1ccc([N+](=O)[O-])cc1N', 'CC(C)CN(CCC=O)CC(C)C', 'CO', 'CC(C)CN(CCC(=O)Nc1cccc([N+](=O)[O-])c1)CC(C)C', 'CC(C)CNCC(C)C', 'CCC(=O)Nc1cc([N+](=O)[O-])ccc1OC', 'CC(C)C', 'COc1ccc([N+](=O)[O-])cc1NC(=O)CCNCC(C)C', 'COc1ccc([N+](=O)[O-])cc1', 'CC(C)CN(CCC(N)=O)CC(C)C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.