['CCO', 'CC(C)N(CC=O)CCN1C(=O)NC(C)(C)C1=O', 'CC', 'CC(C)N(CCN1C(=O)NC(C)(C)C1=O)CC(=O)O', 'CCOC(C)=O', 'CC(C)NCCN1C(=O)NC(C)(C)C1=O', 'CCOC(=O)CNC(C)C', 'CCN1C(=O)NC(C)(C)C1=O', 'CCC', 'CCOC(=O)CNCCN1C(=O)NC(C)(C)C1=O', 'CC1(C)NC(=O)NC1=O', 'CCOC(=O)CN(CC)C(C)C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C1CNC(=O)N1.