Studies On The Chemical Constituents And Bioactivities Of Sophora Flavescens Aition

The genus Sophora, belonging to Leguminosae family, consists of more than 90 species in the world, which are distributed in warm and subtropical area; about 30 species grow in China. So far, the chemical constituents, which mainly include alkaloids, flavonoids, phenols, terpenes ect., were isolated from the genus Sophora. Sophora flavescens Aition, a member of the genus Sophora, is widely distributed in China except for Qinghai and Xinjiang. The roots of S. flavescens, which are bitter in taste and have cold proterty, possess the efficacy of relieving internal heat and drying damp, killing worms and treating diuresis etc. The major actively functional constituents include isopentenyl flavonoids and alkaloids such as matrine, oxymatrine, sophoridine as well as sophcarpine.In order to explore much more medical potential constituents of traditional Chinese medicine, this thesis studied the chemical constituents of the dry roots of S. flavescens. The chemical constituents were isolated by means of silica gel column chromatography (CC), preparative thin layer chromatography (PTLC) and recrystallization ect., and more than 60 compounds were obtained. The structures of 58 compounds were elucidated by spectroscopic methods: UV, IR, MS, ¹H NMR, ¹³C NMR, DEPT, 2D-NMR, NOE and CD, along with a comparison with authentic samples or the data from literature. They were identified as isopentenylflavanones, pterocarpanes, isoflavanones, phenylpropanoids, lignans and triterpenes ect., 9 of which are new compounds, including two biflavanones, two flavanones, two flavanonols, one flavonol, one pterocarpane derivatives and one lignans. Furthermore, one cis-chalcone was isolated from nature for the first time.Validating the biosynthesis of the biflavanones and meeting the requirement of bioactive assays, the compound 24, a biflavanone, has been semi-synthesised using chiral catalyzer by the method of assynthesis. Meanwhile, the bioactivities of some compounds were studied, and the results of bioactive assays indicated that compounds 3, 10, 14 and 21 showed significant antibacterial activity against Staphylococcus aureus; compounds 10, 14, 21 and 36 inhibited Bacilus subtilis strongly; compounds 1,10, 14 and 36 prohibited Escherichia coli effectively.Because of having some specific biological activities, the research on isopentenyflavanones has been focused since 1970s. In the thesis we summerize the structures and the spectral characters of isopentenyflavanones of S. flavescens.The results of this investigation were expected to enrich the database of natural products, to supply a significant scientific basis for pharmacology, chemotaxonomy, screening of new medicines and biosynthesis.