Studies On The Chemical Constituents Of Two Medicinal Plants From Xishuangbanna

This paper consists of three chapters: The first chapter reviewed the research progress in the antihypertensive chemical compositions from the genus Syzygium since 1996.The second chapter discussed the chemical constituents from the leaves of Syzygium austroyunnanese.The third chapter discussed the chemical compositions of the petroleum ether extracts from the aerial part of Euphorbia lactea.In the first chapter,we reviewed the research progress in the chemical compositions of antidiabetic activities from Syzygium since 1996.It mainly list the structures,plants origin and chemical compositions of anti-diabetic activity in the genus Syzygium.In the second chapter,we researched the components of leaves of Syzygium austroyunnanese.The genus Syzygium,belonging to Myrtaceae,were mainly distributed in Xishuang Banna,Yunnan Province and Heng County,Guangxi Province,China.23 compounds were obtained from the petroleum ether part of methanol extract of S.austroyunnanese by means of reversed-phase silica gel column chromatography,Sephadex-LH20 column chromatography,MCI and RP-18 medium pressure liquid chromatography(MPLC)and high performance liquid chromatography(HPLC).Among them,14 are new compounds.The structural types include phloroglucinol derivatives and triterpenes,and all of them were isolated from this plant for the first time.In the third chapter,we studied on the petroleum ether of the aerial part of Euphorbia lactea,mainly grown in the tropics,which are used for the treatment of cancer,lumps,wart,etc.in Chinese folk.Seven compounds,including diterpenes,triterpenes and sterols,were obtained from the petroleum ether part of 70% acetone extract of the aerial part of E.lactea by using various separation techniques and spectroscopic methods.Compounds 24-29 were firstly isolated from this plant.