['CC(C)C(=O)NCCNC=O', 'CCc1ccc(CNC)cc1', 'CC(C)C(=O)NCCN', 'CCc1ccc(CN(C)C=O)cc1', 'CC(C)C=O', 'CCc1ccc(CN(C)C(=O)NCCN)cc1', 'CCc1ccc(C)cc1', 'CNC(=O)NCCNC(=O)C(C)C', 'CCNC(=O)C(C)C', 'CCc1ccc(CN(C)C(N)=O)cc1', 'CC(C)C(N)=O', 'CCNC(=O)N(C)Cc1ccc(CC)cc1', 'CC', 'CC(C)C(=O)NCCNC(=O)N(C)Cc1ccccc1', 'CCc1ccccc1', 'CC(C)C(=O)NCCNC(=O)N(C)C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.