['CO', 'CC(C=O)CN(C)C(=O)c1cc(Cl)c2c(c1)OCO2', 'CNCC(C)C(=O)OC', 'O=Cc1cc(Cl)c2c(c1)OCO2', 'COC(=O)C(C)C', 'CNC(=O)c1cc(Cl)c2c(c1)OCO2', 'Clc1cccc2c1OCO2', 'COC(=O)C(C)CN(C)C=O']
The Murcko scaffold (minmal number of connected rings) of <smiles></smiles> is c1ccc2c(c1)OCO2.