['CO', 'COc1ccc(C)c(S(=O)(=O)NNc2nc(C)cc(C)n2)c1', 'COc1ccc(S(=O)(=O)NNc2nc(C)cc(C)n2)c(C)c1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=S(=O)(NNc1ncccn1)c1ccccc1.