['O=[SH](=O)c1ccccn1', 'C[C@@H]1CN(C2CCOCC2)CCN1', 'C1CCOCC1', 'C[C@@H]1CNCCN1S(=O)(=O)c1ccccn1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=S(=O)(c1ccccn1)N1CCN(C2CCOCC2)CC1.