['C[SH](=O)=O', 'Cc1cc2nc(N3CCNCC3)c3ccccc3n2n1', 'CS(=O)(=O)N1CCNCC1', 'Cc1cc2ncc3ccccc3n2n1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc2c(c1)c(N1CCNCC1)nc1ccnn12.