['CCO', 'CO[C@H]1CN[C@@H](C=O)C1', 'CC', 'CO[C@H]1CN[C@@H](C(=O)O)C1', 'CO', 'CCOC(=O)[C@H]1CCCN1', 'CCOC=O', 'CO[C@@H]1CCNC1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is C1CCNC1.