['OCCO', 'COc1ccc(S(N)(=O)=O)cc1C=O', 'CCO', 'COc1ccc(S(N)(=O)=O)cc1C(=O)O', 'CO', 'NS(=O)(=O)c1cccc(C(=O)OCCO)c1', 'O=COCCO', 'COc1ccc(S(N)(=O)=O)cc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.