['CC', 'CC(NCCCO)c1cc2ccccc2o1', 'CCCO', 'CCNC(C)c1cc2ccccc2o1', 'CCNCCCO', 'CCc1cc2ccccc2o1', 'CCN(CC)CCCO', 'c1ccc2occc2c1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc2occc2c1.