['CO', 'Cc1cc(C(=O)N(C)CC(C)C=O)c2c(C)noc2n1', 'CNCC(C)C(=O)OC', 'Cc1cc(C=O)c2c(C)noc2n1', 'COC(=O)C(C)C', 'CNC(=O)c1cc(C)nc2onc(C)c12', 'COC(=O)C(C)CN(C)C=O', 'Cc1ccc2c(C)noc2n1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1cnc2oncc2c1.