['c1cncnc1', 'O=C(/N=C1/NCc2ccccc21)c1ccccc1', 'c1ccccc1', 'O=C/N=C1\\c2ccccc2CN1c1ncccn1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C(/N=C1\c2ccccc2CN1c1ncccn1)c1ccccc1.