['Cc1ccccc1C=O', 'CC(C)CNC(=O)CCN', 'CC(C)CN', 'Cc1ccccc1C(=O)NCCC=O', 'CCC(=O)NCC(C)C', 'Cc1ccccc1C(N)=O', 'CC(C)C', 'Cc1ccccc1C(=O)NCCC(N)=O', 'Cc1ccccc1', 'CC(C)CNC(=O)CCNC=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.