['CO', 'CCOCCNc1snc(Cl)c1C#N', 'CCOC', 'N#Cc1c(Cl)nsc1NCCO', 'COCCO', 'CCNc1snc(Cl)c1C#N', 'CCOCCOC', 'N#Cc1c(Cl)nsc1N', 'COCCOCCN', 'N#Cc1csnc1Cl']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1cnsc1.