Abstract:
Chemical investigation of the leaves and stems of Pseuduvaria fragrans resulted in the isolation of seven pure compounds, including a new benzophenone C-glycoside named pseuduvarioside and six known compounds comprising (-)-guaiol, (+)-isocorydine, cyathocaline, isoursuline, N-trans-feruloyltyramine and N-trans-coumaroyltyramine. The structure determination of the isolated compounds was carried out by analysis of their UV, HRS-ESI-MS and NMR data in comparison with previously reported values. All the isolates were evaluated for their α-glucosidase inhibitory activity. Only N-trans-feruloyltyramine and N-trans-coumaroyltyramine exhibited strong activity with IC50 values of 3.58 µM and 0.58 µM, respectively, as compared with the drug acarbose (IC50 985.6 µM). Kinetic studies with Lineweaver-Burk plot analysis revealed that N-trans-feruloyltyramine and N-trans-coumaroyltyramine were uncompetitive inhibitors of this enzyme. This study is the first report of the chemical constituents and α-glucosidase inhibitory activity of P. fragrans.
