['Cc1nnc(C)o1', 'O=[N+]([O-])c1cccnc1S', 'Cc1nnco1', 'CSc1ncccc1[N+](=O)[O-]', 'Cc1nnc(CS)o1', 'O=[N+]([O-])c1cccnc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc(SCc2nnco2)nc1.