1.The Chemical Research On Roots Of Vernonia Cumingiana 2.Study On The Chemical Constituents Of Heteropappus Altaicus 3.Study On The Chemical Constituents Of Eritrichium Rupestre

In this doctoral dissertation, the phytochemical and pharmacological studies were carried out on the two medicinal plants of the family Compositae, Vernonia cumingiana Benth. and Heteropappus altaicus(willd.) Novokr., still on a plant of the family Boraginaceae, Eritrichium rupestre (Pall.) Bunge. Before the research working, the advances in the recent research of chemical constituents, especially sesquiterpenoid lactones and steroidal saponins of genus Vernonia plants, and still chemical constituents and pharmacological activities of the genus Heteropappus were reviewed respectively.Twenty compounds (V1-V20) were isolated from the ethanol extract of the roots of the Vernonia cumingiana Benth. by using the advanced preparative chromatography techniques. And on the basis of the spectroscopic analysis and chemical methods, their structures were analysized and determined as follows: eight new compounds, a new natural compound, and nine compounds from the genus for the first time. Among these new compounds, there are four single glucosides as follows: Vernonioside G (V4), Vernonioside G1 (V6), Vernonioside , G2(V14), Vernonioside G3(V12). Four double glucosides are as follows: Vernonioside H1, (V17), Vernonioside H2 (V18), Vernonioside H3 (V19), Vernonioside H4 (V20). These double glucosides possess a common △7, 9 (11) steroidal nucleus and an 3-O-[α-L-arabinopyranosyl- (1→3)-β-D-glucopyranosyl]. In addition, a new natural product, namely, 24-methyllenelanost-9 (11)-en-3β-ol acetate (V1) was isolated from the plant. 8α-hydroxy-11β, 13- dihydrozaluzanin C (V13) was isolated by original shape from the plant for the first time.The discovery of these steroidal saponins isolated from Vernonia cumingiana , not only added the structure group of the second-motabolites in the genus Vernonia, but also indicated that the continuing research workings can emphasize on the studies of the structure-activity relationship between the antibacterial and such...