['C=C1CCNCC1', 'CC(=O)N1C[C@H](O)C[C@@H]1C=O', 'CC=O', 'C=C1CCN(C(=O)[C@H]2C[C@@H](O)CN2)CC1', 'C=C1CCN(C=O)CC1', 'CC(=O)N1CC[C@@H](O)C1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is C=C1CCN(C(=O)[C@H]2CCCN2)CC1.