['Cc1cc(C=O)on1', 'C=CCNC(=O)CO', 'C=CCN', 'Cc1cc(C(=O)OCC=O)on1', 'C=CCNC(C)=O', 'Cc1cc(C(=O)O)on1', 'C=CC', 'Cc1cc(C(=O)OCC(N)=O)on1', 'Cc1ccon1', 'C=CCNC(=O)COC=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1cnoc1.