['CCO', 'COc1c(Cl)cc(C=O)cc1I', 'CC', 'COc1c(Cl)cc(C(=O)O)cc1I', 'CO', 'CCOC(=O)c1cc(Cl)cc(I)c1', 'CCOC=O', 'COc1c(Cl)cccc1I']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.