['CCCC=O', 'Cc1c(N)cccc1N1C(=O)C(C)NC1=S', 'CCCC(N)=O', 'Cc1ccccc1N1C(=O)C(C)NC1=S', 'CC1NC(=S)NC1=O', 'CCCC(=O)Nc1ccccc1C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C1CNC(=S)N1c1ccccc1.