['CNC(=O)[C@H](C)O', 'O=Cc1cc2c(cc1[N+](=O)[O-])OCCO2', 'CN', 'C[C@@H](C=O)OC(=O)c1cc2c(cc1[N+](=O)[O-])OCCO2', 'CCC(=O)NC', 'O=C(O)c1cc2c(cc1[N+](=O)[O-])OCCO2', 'CNC(=O)[C@H](C)OC=O', 'O=[N+]([O-])c1ccc2c(c1)OCCO2']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc2c(c1)OCCO2.