['CCC', 'Oc1cccc(CNn2cn[nH]c2=S)c1', 'CC(C)O', 'S=c1[nH]ncn1NCc1ccccc1', 'CNn1cn[nH]c1=S', 'CC(C)Oc1ccccc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is S=c1[nH]ncn1NCc1ccccc1.