['CC(=O)CN', 'CC(C)(C)c1ccc(C=O)cc1', 'CC(C)=O', 'CC(C)(C)c1ccc(C(N)=O)cc1', 'CC(=O)CNC=O', 'CC(C)(C)c1ccccc1', 'CC(C)C', 'CC(=O)CNC(=O)c1ccccc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.