['CC(C)NC(C)C', 'O=CC1(c2ccccc2)CCOCC1', 'CCC', 'CC(C)NC(=O)C1(c2ccccc2)CCOCC1', 'CC(C)N(C=O)C(C)C', 'c1ccc(C2CCOCC2)cc1', 'c1ccccc1', 'CC(C)N(C(=O)C1CCOCC1)C(C)C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc(C2CCOCC2)cc1.