['CC(C)C(=O)NCCNC=O', 'COc1ccccc1CCN', 'CC(C)C(=O)NCCN', 'COc1ccccc1CCNC=O', 'CC(C)C=O', 'COc1ccccc1CCNC(=O)NCCN', 'CO', 'CC(C)C(=O)NCCNC(=O)NCCc1ccccc1', 'CCc1ccccc1OC', 'CC(C)C(=O)NCCNC(N)=O', 'CCNC(=O)C(C)C', 'COc1ccccc1CCNC(N)=O', 'CC(C)C(N)=O', 'CCNC(=O)NCCc1ccccc1OC', 'COc1ccccc1', 'CCNC(=O)NCCNC(=O)C(C)C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.