Studies On Chemical Constituents And Bioactivities Of The Stems Of Lespedeza Cuneata(Dum.Cour.)G.Don

Lespedeza cuneata (Dum.Cours.) G.Don is annual herbaceous plant distributed in many countries, which named ’ye guan men’ in Chinese, is a very important traditional medicine, and has been used in the treatments of diabetes, hematuria, insomnia and malnutrition. According to recent studies, L. cuneata has antioxidation, cell protection, anti-inflammatory effects, and antimicrobial activities. Based on the above research, the studies on the compounds of this plant were taken in this paper.Ethanolic extract of L. cuneata was subjected to avariety of chromatographic techniques such as macroporous resin, PRP-512A, silica gel, sephadex LH-20, MPLC and HPLC to obtain compounds. The structures were elucidated on the basis of spectrum and chemical methods. The absolute configurations were identificated by CD and Mo2(OAc)4 induced CD.Finally,98 comounds were isolated, including 10 new compounds.1-3 were new lignin glycosides, namely (+)-(8S,7’S,8’S)-burselignan-9’-O-β-D-glucopyranoside, (+)-(8R,7’S,8’R)-isolariciresinol-9’-O-β-D-fucopyranoside, and (-)-(8S,7’R,8’R)-meth-oxyisoariciresinol-9’-O-α-L-rhamnoside; 4-6 were new phenylpropanoid glycosides, namely cuneataside E and cuneataside F; 6-9 were new glycosides megastigmane derivatives, namely cunemegastigmane A-D; 10 was a new flavonoid glycosides, named 6"-O-acetylisovitexin.In the in vitro assays, compounds 2,4,5,6,21 exhibited hepatoprotective activities against N-acetyl-p-aminophenol (APAP)-induced toxicity in HepG2 (human hepatocellular liver carcinoma cell line) cells, using the hepatoprotective activity drug bicyclol as the positive control. Compound 6 exhibited moderate antioxidation activities.