['CC(C)CNC(=O)CO', 'Cc1cccc2nc(C=O)cn12', 'CC(C)CN', 'Cc1cccc2nc(C(=O)OCC=O)cn12', 'CC(=O)NCC(C)C', 'Cc1cccc2nc(C(=O)O)cn12', 'CC(C)C', 'Cc1cccc2nc(C(=O)OCC(N)=O)cn12', 'Cc1cccc2nccn12', 'CC(C)CNC(=O)COC=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccn2ccnc2c1.