['COCCN', 'CC(C)(C)n1cc(CNCCC=O)cn1', 'CO', 'CCNC(=O)CCNCc1cnn(C(C)(C)C)c1', 'CCOC', 'CC(C)(C)n1cc(CNCCC(N)=O)cn1', 'CCC(=O)NCCOC', 'CC(C)(C)n1cc(CN)cn1', 'Cc1cnn(C(C)(C)C)c1', 'COCCNC(=O)CCN', 'CC(C)C', 'COCCNC(=O)CCNCc1cn[nH]c1', 'CC(C)(C)n1cccn1', 'CNCCC(=O)NCCOC']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1cn[nH]c1.