['O=CNc1ccccc1', 'CC(C)(C)C(N)CCO', 'Nc1ccccc1', 'CC(C)(C)C(CCO)NC=O', 'CC(C)(C)CCCO', 'NC(=O)Nc1ccccc1', 'c1ccccc1', 'CC(C)(C)C(CCO)NC(N)=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.