['CC(C)(C)C=O', 'NCC(=O)NCc1ccccc1Cl', 'NCc1ccccc1Cl', 'CC(C)(C)C(=O)NCC=O', 'CC(C)(C)C(N)=O', 'CC(=O)NCc1ccccc1Cl', 'Cc1ccccc1Cl', 'CC(C)(C)C(=O)NCC(N)=O', 'Clc1ccccc1', 'CNC(=O)CNC(=O)C(C)(C)C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.