Study On The Chemical Constituents And Their Biological Activity Of The Medicinal Plant Tacca Chantrieri

This thesis consists of three chapters.In the first chapters,we have discussed the research status of the genus Tacca.The second chapter was cosisted by two sections,and in the first section,we have discussed the chemical constituents of the methanol extracts from the underground part of plant T.chantrieri and their in vitro cytotoxic activities against five human tumor cell lines..In the second section,the chemical constituents of the methanol extract from the aerial part of T.chantrieri were discussed.At the third chapter,the research progress of taccalonolides in Tacca have been reviewed.As a results,64 compounds,including 19 new ones,were isolated from the aerial and underground part of T.chantrieri by means of normal phase column chromatography（CC）,reversed phase silica gel CC,Sephadex CC,MPLC and semipreparative or preparative HPLC.On the basis of 1D and 2D NMR,as well as high resolution mass spectrometry,ORD,UV,IR and X-ray single crystal diffraction,the structures of the 64 compounds were established.T.chantrieri André,belongs to the Tacceceae family,is a kind of traditional Chinese medicinal plant.Taccalonolides,a group of steroidals possessed highly acetylated pentacyclic skeleton,is the main and unique compounds in the plants of this genus.A total of 49compounds were isolated and identified from the methanol extract of the underground part of T.chantrieri,including 16 new ones.Among them,34 ones are taccalonolides and 10 ones are withanolides.The new compounds taccachatrones A—D（1—4）are four novel taccalonolide derivatives with a trinor-carbon skeleton.This is the first time that this kind of nortaccalonolides have been isolated from the genus Tacca.The absolute structures of taccachatrones A and Bhave been determined by X-ray single crystal diffraction.At the same time,eight other new taccalonolides and four new withanolides were also isolated form this pants.The absolute configurations of plantagiolides O,Q and R were established by ECD calculation and the absolute configurations of plantagiolide O was determined by X-ray single crystal diffraction.The cytotoxic activities of compounds 1—44 were detected by MTS method against five human tumor cell lines as HL-60（leukemia）,A549（lung cancer）,SMMC-7721（liver cancer）,MCF-7（breast cancer）and SW480（colon cancer）with DDP and taxol used as positive controls.The results showed that compound 22 inhibited the activities of five human tumor cells significantly.Compound 23 inhibited SMMC-7721 and MCF-7,while compounds 24and 31 inhibited A549,SMMC-7721 and SW480.The other compounds showed no obvious cytotoxicity(IC₅₀>40μM).In additional,part of this compounds were tested for antinematode activity.As a results,compounds 34 and 36 made the nematode thinner,but cannot kill it.The other compounds have no nematicidal activity.The chemical constituents of the aerial part of T.chantrier have also been studied and 15compounds were isolated and established,among which 3 were new ones.The structures of the new compounds were determined by 1D and 2D NMR and high resolution mass spectrometryasfollows:4′,5′-methylenedioxy-1,5,7-trimethoxyflavan（46）,1-（1,3-benzodioxol-5-yl）-3-（2,4-bimethoxyphenyl）-1-propanone（47）,（2E,6E）-5-hydroxy-3,7-dimethyl-8-oxoocta-2,6-dienoic acid（48）.