Two new aromatic derivatives from Codonopsis pilosula and their alpha-glucosidase inhibitory activities

The ethanol extract of the roots of Codonopsis pilosula was subjected to chromatographic fractionation, which result in the isolation and characterization of two new aromatic derivatives 2,3-dihydroxypropyl 2,4-dihydroxy-3,6-dimethylbenzoate (1) and 2-oxopropyl 3-hydroxy-4-methoxybenzoate (2), along with three known compounds pilosulinene A (3), pollenfuran B (4) and (+)-pinoresinol (5). Their structures were demonstrated by HRESIMS and spectroscopic methods including NMR and IR. It is worth noting that compound 4 was isolated for the first time from the genus Codonopsis. The potential hypoglycemic properties of compounds 2-5 were evaluated by measuring their alpha-glucosidase inhibitory effects. As a result, compounds 2 and 3 showed weak alpha-glucosidase inhibitory activities with IC50 values of 154.8 +/- 11.0 mu M and 24.0 +/- 2.2 mu M, respectively.