['CCNCC', 'CC(C)(C)C(=O)N1CCCC(C=O)C1', 'CC(C)(C)C=O', 'CCN(CC)C(=O)C1CCCNC1', 'CC', 'CCNC(=O)C1CCCN(C(=O)C(C)(C)C)C1', 'CCN(C=O)CC', 'CC(C)(C)C(=O)N1CCCCC1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is C1CCNCC1.