['CC(C)(C)NCC=O', 'Cc1ccnc(N)c1', 'CC(C)(C)N', 'CC(=O)Nc1cc(C)ccn1', 'CC(C)C', 'Cc1ccnc(NC(=O)CN)c1', 'Cc1ccncc1', 'CC(C)(C)NCC(N)=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccncc1.