['CO', 'CCOCCNc1c([N+](=O)[O-])c(C)nn1C', 'CCOC', 'Cc1nn(C)c(NCCO)c1[N+](=O)[O-]', 'COCCO', 'CCNc1c([N+](=O)[O-])c(C)nn1C', 'CCOCCOC', 'Cc1nn(C)c(N)c1[N+](=O)[O-]', 'COCCOCCN', 'Cc1nn(C)cc1[N+](=O)[O-]']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1cn[nH]c1.