Study On The Chemical Constituents And Bioactivities From The Aerial Parts Of Parasenecio Deltophylla.

The parasenecio genus belongs to the family Compositae tribe Senecioneae, which used to be named Cacalia. More than 60 species are distributed mainly over the mountain areas in the Northwestern and Southwestern regions in the People's Republic of China. Approximately 26 species have been used as Chinese traditional folk herbs for invigorating the circulation of blood, curing rheumatismal aches, and injuries from falls, etc.In order to explore biologically active new compounds in the parasenecio genus, we made systemic photochemical studies on the aerial parts of Parasenecio deltophylla, which were collected in Huzhu County of Qinhai province. Consequently,35 compounds were isolated by means of silica gel column chromatography (CC), preparative thin layer chromatography (PTLC), Sephadex LH-20 and medium pressure column chromatography from a mixed solvent (petrol ether-ether-methanol=1:1:1, V:V:V) extraction of the aerial parts of P. deltophylla.34 of them had been elucidated as twelve sesquiterpenes, two monoterpenes, two triterpenes, four sterols, three phenylpropanoids, one aromatic derives, six glycerides and others by spectroscopic methods, such as HRESIMS, EIMS, IR, UV, 1D-NMR (1H,13C-NMR, DEPT, NOE),2D-NMR (1H-1H COSY, HSQC, HMBC) and in combination with comparison to the literature data or authentic samples. Especially, there were seven new compounds 1～5,14, and 15. The bioactivities of selected isolates obtained in this investigation were studied, using MTT method to evaluate their cytotoxic activities against human leukemia HL-60 and human hepatoma HepG2 cells, and ABTS and DPPH methods to evaluate their antioxidation activities. Compound 4 exibited moderate cytotoxic activity against HepG2 with IC50 of 21.76μM. Compound 4 and 14 showed weak cytotoxic activity against HL-60 with IC50 of 49.78 and 47.49μM. The tested compounds had no free radical scavenging capacity for ABTS+ and DPPH'. In addition, this thesis reviewed on the bioactivities of eremophilane-type sesquiterpene from 1995 to 2010.Results of the photochemistry and biological activity in the thesis provide scientific basis for chemotaxonomy, Chinese traditional medicines as well as the screen of new medicines.This study is expected to provide benefits for utilizing and developing the natural plant resources of our country.