['CNC(=O)CO', 'CSc1nc(C=O)c2ccccn12', 'CN', 'CSc1nc(C(=O)OCC=O)c2ccccn12', 'CNC(C)=O', 'CSc1nc(C(=O)O)c2ccccn12', 'CNC(=O)COC=O', 'CSc1ncc2ccccn12', 'CS', 'CNC(=O)COC(=O)c1ncn2ccccc12']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccn2cncc2c1.