['N[C@@H]1CCCc2ccccc21', 'O=Cc1ccc2c(c1)OCCCO2', 'c1ccc2c(c1)OCCCO2', 'O=CN[C@@H]1CCCc2ccccc21']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is O=C(N[C@@H]1CCCc2ccccc21)c1ccc2c(c1)OCCCO2.