['C#CCN', 'O=Cc1ccc(N2CCOCC2)nc1', 'C#CC', 'NC(=O)c1ccc(N2CCOCC2)nc1', 'C1COCCN1', 'C#CCNC(=O)c1cccnc1', 'C#CCNC=O', 'c1ccc(N2CCOCC2)nc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc(N2CCOCC2)nc1.