['C[C@H]1CS(=O)(=O)C[C@H]1N', 'Cn1cc2cncnc2n1', 'C[C@@H]1CCS(=O)(=O)C1', 'Cn1cc2c(N)ncnc2n1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=S1(=O)CC[C@H](Nc2ncnc3n[nH]cc23)C1.