Studies On The Chemical Constituents From Phyllanthus Parvifolius

Phyllanthus is one of the largest genus of the family Euphoriaceae, which contains more than 1000 species, widely describing in South America, Africa and Asia. There are 33 species in China, including 4 mutations. The plants of Phyllanthus have been traditionally used as folk medicine, such as P. emblica, consisting of too many active constituents, which possess cytotoxicity, antiviral bioactivity, liver-protecting and so on. So it is worthy for us to investigate the secondary metabolites of the plants of Phyllanthus deeply.There are many biological secondary metabolities in the genus Phyllanthus, mainly dividing into sesquiterpenoids, diterpenoids and triterpenoids. So we carried out a work on the stem bark of P. parvifolius from Hainan Province, which had never been studied before, to seek for structurally novel and biologically active compounds to enrich the genus Phyllanthus. During this experiment, we mainly utilize the methods of macroporous resin, MCI, silica gel column chromatography, high performance liquid chromatography and Sephadex LH-20 to isolate 30 coupounds in total. For the sake of the structural elucidation of these compounds, we make use of the modern spectroscopic technology (IR, HRESIMS,1H NMR,13C NMR, DEPT, ’H-’H COSY, HSQC, HMBC, NOESY and CD). We have confirmed 28 compounds so far, comprising 6 new compounds,4 of which are cleistanthane diterpenoids, the rest of which are lupane and friedelane triterpenoids. At the end of this research,7 compounds were tested for their in vitro cytotoxicities against human lung cancer cell A549 using the MTT method, and 4 compounds exhibited moderate cytotoxicity with IC50 value between 20-40μmol/L. At last, we conclude the diterpenoids and triterpenoids isolated from Phyllanthus.We hope our work can be helpful for the research on chemotaxonomy, the bioactive constituents in traditional Chinese medicine, pharmacology, and screening new medicines, and it may contribute to the use and development of the natural resources in our country.