['C[C@@H](O)C(N)=O', 'O=CCCc1nc(-c2ccccc2)no1', 'CCC(N)=O', 'O=C(O)CCc1nc(-c2ccccc2)no1', 'CCC(=O)O[C@H](C)C(N)=O', 'c1ccc(-c2ncon2)cc1', 'c1ccccc1', 'C[C@@H](OC(=O)CCc1ncno1)C(N)=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc(-c2ncon2)cc1.