['CC(C)O', 'Cc1cc2ncn([C@@H](C)C=O)c2cc1C', 'CCC', 'Cc1cc2ncn([C@@H](C)C(=O)O)c2cc1C', 'CCC(=O)OC(C)C', 'Cc1cc2nc[nH]c2cc1C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc2[nH]cnc2c1.