['N[C@@H]1CCCOC1', 'CC(C)(C=O)N1CCOCC1', 'C1COCCN1', 'CC(C)C(=O)N[C@@H]1CCCOC1', 'C1CCOCC1', 'CC(C)(C(N)=O)N1CCOCC1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C(CN1CCOCC1)N[C@@H]1CCCOC1.