['CO', 'O=C(/C=C/c1cc2ccccc2o1)c1cccc(Br)c1', 'COc1ccc(Br)cc1', 'O=C/C=C/c1cc2ccccc2o1', 'Cc1cc2ccccc2o1', 'COc1ccc(Br)cc1C(C)=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C(/C=C/c1cc2ccccc2o1)c1ccccc1.