['CCN', 'CN(CCC=O)Cc1cccc(C#N)c1', 'CC', 'CN(CCC(N)=O)Cc1cccc(C#N)c1', 'CCNC(=O)CC', 'CNCc1cccc(C#N)c1', 'Cc1cccc(C#N)c1', 'CCNC(=O)CCNC', 'N#Cc1ccccc1', 'CCNC(=O)CCN(C)C']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccccc1.