['CC(C)(C)O', 'CC1(C)[C@@]2(NC=O)CC[C@]1(C)C(=O)C2', 'CC(C)(C)OC=O', 'CC1(C)[C@@]2(N)CC[C@]1(C)C(=O)C2', 'CC(C)C', 'CC1(C)[C@@]2(NC(=O)O)CC[C@]1(C)C(=O)C2', 'CC(C)(C)OC(N)=O', 'CC1(C)[C@@H]2CC[C@]1(C)C(=O)C2']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C1CC2CCC1C2.