Seven new secondary metabolites isolated from roots of Lespedeza bicolor

Abstract

Chemical investigation of a methanol extract obtained from the roots of Lespedeza bicolor identified one new pterocarpene (1), three new pterocarpans (2–4), and three new arylbenzofurans (5–7), and two known compounds (8 and 9). Their structures were determined by interpretations obtained from combined UV, NMR, and HRTOFMS spectroscopic data. Furthermore, the absolute configurations of compounds 2 and 3 were established by the combination of electronic circular dichroism (ECD) calculations and NMR calculations with DP4+ probability analysis. All isolated compounds (1–9) were evaluated for cytotoxicity against the human lung carcinoma cell line A549 and the human hepatoma cell line Huh-7. Compound 4 showed antiproliferative activity against A549 cell line with IC50 value of 24.9 μM. Furthermore, compound 9 exhibited cytotoxicity against Huh-7 cell line with IC50 value of 68.7 μM.