['CN', 'CN(CC=O)C(=O)C1CCCN(C(=O)C(C)(C)C)C1', 'CNCC(=O)NC', 'CC(C)(C)C(=O)N1CCCC(C=O)C1', 'CC(C)(C)C=O', 'CNC(=O)CN(C)C(=O)C1CCCNC1', 'CNC(C)=O', 'CNC(=O)C1CCCN(C(=O)C(C)(C)C)C1', 'CNC(=O)CN(C)C=O', 'CC(C)(C)C(=O)N1CCCCC1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is C1CCNCC1.