['CO', 'O[C@@H]1CCCC[C@H]1Cc1ccccc1', 'OC1CCCCC1', 'COc1ccc(C)cc1', 'C[C@@H]1CCCC[C@H]1O', 'COc1ccccc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc(CC2CCCCC2)cc1.