['FC(F)(F)c1ccncn1', 'NC(=O)[C@@H]1Cc2ccccc2CN1', 'NC=O', 'FC(F)(F)c1ccnc(N2CCc3ccccc3C2)n1', 'FC(F)F', 'NC(=O)[C@@H]1Cc2ccccc2CN1c1ncccn1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1cnc(N2CCc3ccccc3C2)nc1.