['CC(C)(C)NCC=O', 'Nc1ccccc1O', 'CC(C)C', 'NCC(=O)Nc1ccccc1O', 'CC(C)(C)N', 'CC(=O)Nc1ccccc1O', 'Oc1ccccc1', 'CC(C)(C)NCC(N)=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.