['CCCO', 'CC(=O)c1cc(C=O)c(O)cc1O', 'CCC', 'CC(=O)c1cc(C(=O)O)c(O)cc1O', 'CCCOC=O', 'CC(=O)c1ccc(O)cc1O', 'CC=O', 'CCCOC(=O)c1ccc(O)cc1O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.