['CC(C)(C)N', 'CS(=O)(=O)C1CCCN(C=O)CC1', 'CC(C)(C)NC=O', 'CS(=O)(=O)C1CCCNCC1', 'CC(C)C', 'CS(=O)(=O)C1CCCN(C(N)=O)CC1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is C1CCCNCC1.