['CC(C)(C)CC=O', 'NCCNC(=O)c1ccc(Cl)cc1', 'O=Cc1ccc(Cl)cc1', 'CC(C)(C)CC(=O)NCCN', 'CC(C)(C)CC(N)=O', 'CCNC(=O)c1ccc(Cl)cc1', 'CCNC(=O)CC(C)(C)C', 'NC(=O)c1ccc(Cl)cc1', 'Clc1ccccc1', 'CC(C)(C)CC(=O)NCCNC=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.