['CNCc1ccccc1C', 'CC(C)C(=O)NCCNC=O', 'CC(C)C(=O)NCCN', 'Cc1ccccc1CN(C)C=O', 'CC(C)C=O', 'Cc1ccccc1CN(C)C(=O)NCCN', 'Cc1ccccc1C', 'CNC(=O)NCCNC(=O)C(C)C', 'CCNC(=O)C(C)C', 'Cc1ccccc1CN(C)C(N)=O', 'CC(C)C(N)=O', 'CCNC(=O)N(C)Cc1ccccc1C', 'Cc1ccccc1', 'CC(C)C(=O)NCCNC(=O)N(C)C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.