['CCC', 'Cc1[nH]c2ccc(O)cc2c1CCN', 'CC(C)O', 'Cc1[nH]c2ccccc2c1CCN', 'CCN', 'Cc1cc2cc(OC(C)C)ccc2[nH]1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc2[nH]ccc2c1.