Studies On The Chemical Constituents And Bioactivities Of Veratrum Nigrum And Ligularia Latihastata

This dissertation mainly reported the investigation on the chemical constituents in the roots and rhizomes of Chinese medicinal plant Veratrum nigrum L. and Ligularia latihastata (W.W. Smith) Hand.-Mazz.. Totally compounds were isolated and identified by modern isolation and purification methods, such as silica gel column chromatography, MPLC, MCI, Sephadex LH-20, PTLC and HPLC. Their chemical structures were elucidated on the basis of spectral data (EI-MS、(±) ESI-MS and1D、2D-NMR) together with phytochemical analysis. Among them, four compounds were new ones, the types of which included one steroid alkaloids, two oleanane-type triterpenes and one benzofuran derivative. The types of the known compounds included triterpenes, benzofuran derivatives, stilbene derivatives and steroid alkaloids. In vitro cytotoxic bioassay studies by MTT method indicated that5-acetyl-6-hydroxy-2-isopropenylbenzofuran (3) which was isolated from Ligularia latihastata exhibited the strong ability to cytotoxic activity against Hela human cervical carcinoma cancer cells with IC50values of36.0μmol/L, and corresponded to the clinical drug cisplatin (cis-platinum), hasing the value of further development and utilization.Veratrum nigrum L. belongs to genus Veratrum (Liliaceae), which is a famous toxic plant in China, distribute worldwidely. The roots and rhizomes of Veratrum nigrum L., known as "Li Lu" in China, which is used for treatment of hypertension, blood-stroke, excessive phlegm, epilepsy, etc. Our present study on the constituents of the roots and rhizomes of this plant collected in Sichuan province resulted in the isolation of16compounds, including one new compounds.Ligularia latihastata, belongs to genus Ligularia (Compositae), which is a perennial herb, inhabit the Hengduan Mountains in northwestern Yunann province and mainly distribute in Lijiang zone. The roots of L. latihastata have been used as a Chinese herbal medicine known as ’Shanziyuan’, which is used against cough and asthma. At present, there are only a few reports about the chemical constituents of L. latihastata, hence, the phytochemical researches on the roots of L. latihastata were carried out, which led to isolation of27compounds, including three new compounds.