['C[C@@H]1CN(C)[C@@H](C)CO1', 'O=c1[nH]nc(-c2ccc(F)cc2)o1', 'Fc1ccccc1', 'C[C@@H]1CN(Cn2ncoc2=O)[C@@H](C)CO1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=c1oc(-c2ccccc2)nn1CN1CCOCC1.