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