Chemical Constituents From Three Magnolia Species And Their Biological Activities

This paper consists of four chapters.Chapter one reported the chemical composition and biological activity from the leaves of Magnolia delavayi.Chapter two was the research on chemical composition and biological activity of the leaves of Magnolia denudata.The third chapter was the chemical composition from the leaves of Magnolia liliflora.In the last chapter,we summarized the progress of the chemical constituents and pharmacological activities of sesquiterpenes in Magnolia.By the means of chromatography methods,spectroscopic evidences,MS,IR,UV,crystal X-ray methods,more than 100 compounds were isolated and identified from three genus of Magnolia,which 19 compounds were new.The main compounds identified were sesquiterpenes and lignans.Some of the isolated compounds were evaluated for cytotoxicity against five human cancer cell lines and NO inhibitory activity.As a result,two sesquiterpenes exhibited cytotoxicity activity.The first chapter introduce the chemical constituents and bioactivities from the leaves of M.delavayi.M delavayi is mainly distributed in Southwestern China,and has been used as traditional folk medicine to treat indigestion,chronic gastritis,cough,and bronchitis.However,its chemical constituents were barely investigated.In this study,a 95%ethanolic extract of the leaves of M.delavayi were phytochemical studied,which resulted in the isolation of 35 compounds including 10 new compounds.Some of the compounds were evaluated for their cytotoxic activity and it was found that two compounds exhibited significant cytotoxicity activity against five tumor cell lines.The second chapter focuse on research about the chemical constituents and bioactivities of M.denudate.M.denudata is native to easterm and southern China.Its dried flower buds,known as Xin Yi in traditional Chinese herbal medicine,have been used for treatment of emphysema,nasal congestion,sinusitis,and allergic rhinitis.It has been also reported to contain many kinds of lignans and neolignans.In this study,52 compounds were isolated from 95%ethanol extracts of this plant,including 9 new compounds.The inhibitory activity of NO formation was studied on some of the isolated compounds were further evaluated for their capability to inhibit NO production,only one compound exhibited weak inhibitory activity against NO formation at 50 ?M.The third chapter detaile the chemical composition of M.liliflora.M.liliflora was a deciduous shrub propagated and distributed in many parts of East Asia and North America.It has been reported that M.lilifora has the beneficial effects on several ailments such as analgesic,anodyne,carminative,febrifuge,sedative,and tonic.In this study,13 compounds were isolated from the leaves.The fourth chapter summarize the progress of the chemical constituents and pharmacological activities of sesquiterpenes in Magnolia.