['COCCOCCN', 'O=Cc1cc(Cl)ccc1O', 'CO', 'CCOCCNC(=O)c1cc(Cl)ccc1O', 'CCOC', 'O=C(NCCO)c1cc(Cl)ccc1O', 'COCCO', 'CCNC(=O)c1cc(Cl)ccc1O', 'CCOCCOC', 'NC(=O)c1cc(Cl)ccc1O', 'Oc1ccc(Cl)cc1', 'COCCOCCNC=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.