Phenolic Constituents with Glucose Uptake and GLUT4 Translocation Bioactivities from the Fruits of .

From the fruits of , 11 new phenolic compounds, dichotomins A-K, were isolated, together with 19 known compounds. Through the analysis of detailed NMR data and HRESIMS data, the planar structures of all compounds were confirmed. Using NMR calculations, the absolute configuration of dichotomins A-K was elucidated by comparing their observed and computed electronic circular dichroism (ECD) spectra. Dichotomin H () and dichotomin I () were determined as two pairs of enantiomers. The enantiomers of compounds and were separated using chiral-phase high-performance liquid chromatography (HPLC), and the stereostructure of each enantiomer was determined by similarly calculating the ECD. Compounds , , , , -, and - increased glucose uptake by 1.04- to 2.85-folds at concentrations of 30 μg/mL. Further studies revealed that compounds and had a moderate effect on glucose transporter 4 (GLUT4) translocation activity in L6 cells. At 30 μg/mL, compound significantly enhanced AMPK phosphorylation and GLUT4 expression. As a whole, compound has the potential to be a drug candidate for the treatment of type 2 diabetes mellitus (T2DM).