['CCc1ccc(N)cc1', 'CC(C)(C)C(=O)NCC=O', 'CC(C)(C)C=O', 'CCc1ccc(NC(=O)CN)cc1', 'CC(C)(C)C(N)=O', 'CCc1ccc(NC(C)=O)cc1', 'CCc1ccccc1', 'CC(C)(C)C(=O)NCC(N)=O', 'CC', 'CC(C)(C)C(=O)NCC(=O)Nc1ccccc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.