['NCCO', 'N#CCCN1CCC(C=O)CC1', 'CCC#N', 'O=C(NCCO)C1CCNCC1', 'CCO', 'N#CCCN1CCC(C(N)=O)CC1', 'O=CNCCO', 'N#CCCN1CCCCC1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is C1CCNCC1.