['CC(C)(C)N', 'O=Cc1ccccc1NC(=O)CC(F)(F)F', 'O=CCC(F)(F)F', 'CC(C)(C)NC(=O)c1ccccc1N', 'CC(C)C', 'NC(=O)c1ccccc1NC(=O)CC(F)(F)F', 'NC(=O)CC(F)(F)F', 'CC(C)(C)NC(=O)c1ccccc1', 'CC(C)(C)NC=O', 'O=C(CC(F)(F)F)Nc1ccccc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.