Studies On The Chemical Constituents And Bioactivities Of One Rosaceae And Two Compositae Species

More than 200 species of Potentilla plants are distributed throughout the world, and about 90 species are widespread in China. Some species of them have long been used as traditional Chinese medicinal herbs as antirheumatic, for detoxification, and curing dysentery and scabies. The characteristic components of this genus are triterpenoids and tannins. The constituents of Potentilla multicaulis had not been found to be reported about its constituents.The genus Ligularia has been taxonomically placed in the Compositae with ca. 100 species distributed within China, more than 20 species have long been used for folk medicines. Their roots, stems, leaves, and flowers possess efficacies of antipyretic, relieving phlegm and cough, invigorating circulation of blood, and soothing pain. The main components of them are eremophilane sesquiterpenes and pyrrolizidine alkaloids with strong physiological actvities. In our long-standing interest in the study of biodiversity and searching for bioactive compounds from several Ligularia species, those results showed that the components from the same genus, even from the same species, displayed a remarkable difference because of the differences of ecological environments and collection seasons. The constitutes study of the plant Ligularia sagitta mattf would show us the relations between chemical constituents and ecology circumstance.The plant Artemisia angustissima Nakai is the genus Artemisia of the family Compositae. More than 300 species were found widely in the world. About 186 species are distributed in China, mainly distributed in the north area. Some species of them such as A.annua L,A. apiacea Hance,A capillaris Thunb, and A.argyi Levl. et Vant. are used as traditional Chinese medicinal herbs. So it will be significative to study the plants of the genus Artemisia.In this thesis we studied the chemical constituents of the three plants mentioned above. The chemical constituents of 82 compounds were isolated by means of silica gel column chromatography (CC), preparative layer chromatography (PTLC), recrystallization and chemical transformatione etc. 23 compounds of them were new, including 2 new triterpanoids with novel taraxerane skeleton, 2 new sesquiterpenes with new carbon skeleton, and 2 new novel dimeric sesquiterpenes. The structures of these compounds were elucidated by spectroscopic methods: UV, IR, EI-MS, FAB-MS, HR-MS, ¹H NMR, ¹³C NMR, DEPT, NOEDS, ¹H-¹H COSY, HSQC, HMBC, ¹H-¹H NOESY, and X-ray crystallography.Furthermore the bioactivities of some compounds were studied, using SRB method to test their cytotoxic activities against human promyelocytic leukemia (HL-60) cells, human hepatoma (SMMC-7721) cells, and human cervical carcinoma (HeLa) cells. Compound P2b exhibited weak cytotoxic activity against HL-60 cells, L8a exhibited moderate cytotoxic activity against HL-60 and SMMC-7721 cells, and compounds L16 and L17 showed weak cytotoxic activity against HL-60 cells.Finally, tetracyclic triterpenoids from natural products reported from 1997 to 2007 were reviewed in this thesis.This thesis would be a helpful reference for the research of biodiversity and searching for bioactive compounds from natural products, as well as chemotaxonomy and the relationship between structure and bioactivity effect.