['CC(C)CC(C)O', 'O=Cc1ccc(N2CCNC2=O)cc1', 'CCCC(C)C', 'O=C(O)c1ccc(N2CCNC2=O)cc1', 'CC(C)CC(C)OC=O', 'O=C1NCCN1c1ccccc1', 'O=C1NCCN1', 'CC(C)CC(C)OC(=O)c1ccccc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C1NCCN1c1ccccc1.