Chemical constituents and bioactivities of the leaves and stems of pseuduvaria fragrans

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.