['COCCOCC=O', 'CCOC1CCCNC1', 'CC', 'COCCOCC(=O)N1CCCC(O)C1', 'COCCO', 'CCOC1CCCN(C(C)=O)C1', 'CCOC', 'CCOC1CCCN(C(=O)CO)C1', 'CO', 'CCOCC(=O)N1CCCC(OCC)C1', 'CCO', 'COCCOCC(=O)N1CCCCC1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is C1CCNCC1.