['O=C/C=C/c1ccccc1', 'CN1CCc2c(N)cccc2C1', 'NC(=O)/C=C/c1ccccc1', 'CN1CCc2ccccc2C1', 'Cc1ccccc1', 'CC(=O)Nc1cccc2c1CCN(C)C2']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C(/C=C/c1ccccc1)Nc1cccc2c1CCNC2.