['CCO', 'CC(C)c1ncc(C=O)c(CCl)n1', 'CC', 'CC(C)c1ncc(C(=O)O)c(CCl)n1', 'CCOC=O', 'CC(C)c1nccc(CCl)n1', 'CCC', 'CCOC(=O)c1cncnc1CCl', 'CCl', 'CCOC(=O)c1cnc(C(C)C)nc1']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1cncnc1.