['CC(C)CC(C)O', 'CN1C(=O)c2ccc(C=O)cc2C1=O', 'CCCC(C)C', 'CN1C(=O)c2ccc(C(=O)O)cc2C1=O', 'CC(C)CC(C)OC=O', 'CN1C(=O)c2ccccc2C1=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C1NC(=O)c2ccccc21.