['CC(C)CC(C)O', 'Cc1[nH]c(=O)c(C#N)c(C)c1CCC=O', 'CCCC(C)C', 'Cc1[nH]c(=O)c(C#N)c(C)c1CCC(=O)O', 'CCC(=O)OC(C)CC(C)C', 'Cc1cc(C)c(C#N)c(=O)[nH]1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=c1cccc[nH]1.