Study On Chemical Constituents Of Senecio Scandens And Ligularia Fischeri

This dissertation studied the chemical constituents of two medicinal plants of Compositae (Senecio scandens and Ligularia fischeri). All kinds of modern chromatographic techniques including silica gel, Sephadex LH-20, ODS C18, MCI gel CHP-20, Toyopearl HW-40(C) and so on were used to isolate the chemical constituents of the two plants. Modern spectroscopic techniques such as physical and chemical methods, MS,1H-NMR, 13C-NMR and 2D-NMR were used to identify the compounds. Structural modification work on the main compound petasin of Ligularia fischeri has been done and HPLC analysis was performed on the sesquiterpenes that were isolated from Ligularia fischeri. The main work of this thesis is as follows:1. Study on chemical constituents of Senecio scandensSenecio scandens (compositae) is one of the most popular species used as a traditional Chinese medicinal herb in the folk. In this thesis we studied the rhizomes of Senecio Scandens distributed in Funiu mountains, Henan province. Finaly,6 compounds were isolated and identified as 19a-H lupeone (S-1), sucrose (S-2),β-sitosterol (S-3), daucosterol (S-4), linoleic acid (S-5) and pentacosoic acid (S-6). Among them, S-1, S-2, S-5 and S-6 were first isolated from this plant. And the structure of S-1 was identified by 1H-NMR,13C-NMR and 2D-NMR.2. Study on chemical constituents of Ligularia fischeriLigularia fischeri is a plant of ligularia genera of compositae. Its rhizomes named "shan zi wuan" can moisturize the lung and have antitussive and expectorant effects. Its roots as a herbal medicine has a long history in drug use in the folk. In this part we studied Ligularia fischeri distributed in taihang mountains, Henan province. The study was carried out mainly on the following aspects:(1) Extract and isolation of the roots of Ligularia fischeri:16 compounds were isolated and indentified asβ-sitosterol (L-1), daucosterol (L-2), protocatechual dehyde (L-3),7-hydroxychromone (L-4), caffeic acid (L-5), caffeic acid methyl ester (L-6), angelic acid (L-7), Pentatriacontane (L-8), petasin (L-9), isopetasin (L-10), isopetasan (L-11), neopetasan (L-12), isopetasol (L-13), petasol (L-14), 3a-Tigloyloxy-eremophila-9,11-dien-8-one (L-15),1,5-dicaffeoylquinic acid (L-16). Among them, compounds L-3-L-16 were reported from this plant for the first time.(2) Structure modification:Structure modification work on the petasin has been done.7 derivatives were got and 3 of them were new compounds.(3) HPLC analysis of sesquiterpenes isolated from Ligularia fischeri:A qualitative analysis on the roots, stems, leaves and flowers was taken out. We got the realationship of seven sesquiterpenes in Ligularia fischeri corresponding to seven peaks in the HPLC spectrum. The result shows that roots and flowers contain a large amount of sesquiterpenes, while the content of them in leaves and stems is very low. Later, the content of petasin in the roots of Ligularia fischeri was measured. The content is 15.24 mg/g dried materials.