['CC(C)(C)O', 'N#CCCN1CCN(C=O)CC1', 'CC(C)(C)OC=O', 'N#CCCN1CCNCC1', 'CC(C)C', 'N#CCCN1CCN(C(=O)O)CC1', 'CCC#N', 'CC(C)(C)OC(=O)N1CCNCC1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is C1CNCCN1.