Studies On Chemical Constituents And Their Bioactivities From The Leaves Of Cajanus Cajan And The Flowers Of Syzygium Jambos

Part one Studies on chemical constituents and their bioactivities from the leaves of Cajanus cajanThe plant C.cajan is one of the representative genera in the Leguminosae family.It is originated in India,and mainly distributed in the southwest of China,and now,it has been commercially cultivated throughout tropical and subtropical regions of the world,as well as widely used as medicinal plant,food,and fodder.Previously,some stilbene compounds were isolated from the leaves of C.cajan by our research group,which have effects including resensitizing insulin resistance,anti-osteoporosis,cytotoxicites.However,the research on the chemical constituents from the leaves of C.cajan with various biological activities was not deep enough,so the thesis will continue to study the chemical constituents from the leaves of C.ca jan and their biological activities.ObjectiveNew compounds were isolated and identified from the dichloromethane fraction of ethanol extract from the loaves of C.cajan,and the biological activities of the new compounds were testedMethodsIsolation of compounds in dichloromethane fraction was carried out by means of normal-phase and reversed-phase column chromatographies with silica gel,ODS,and sephadex as stationary phases,high performance liquid chromatography(HPLC),as well as recrystallization.The chemical structures were identified by analysis of spectroscopic data of NMR(1H-1H COSY,IIMQC,HMBC),IR,UV,and MS including HR-ESI-MS.Results1.Three new prenylated stilbenes,named as cajanusins A-C(SD-1 to SD-3),and one new natural product cajanusin D(SD-4),along with six known derivatives 5-hydroxy-6,7-(2’’,2’ ’-dimethylchromene)flavanone(SD-5),longistylin A(SD-6),longistylin C(SD-7),cajanolactone A(SD-8),pinostrobin(SD-9),cajanonic acid A(SD-10)were isolated from the leaves of C.cajan.2.The cytotoxicites of new compounds SD-1(cajanusin A)and SD-2(cajanusin B)against human cancer cell lines(Hela,MCF-7,OVCAR 3,C33A,T47D and HepG2 cells)were evaluated in vitro.These two compounds showed weak inhibitory effect on the proliferation of human breast tumor MCF-7 cells with IC50 values as 86.6±7.5 μM and 77.6±0.3 μM.While they did not show cytotoxicity to proliferation of other tumor cells,with IC50 values all greater than 100 μM.3.The anti-microbial activities of compounds SD-3(cajanusin C)and SD-4(cajanusin D)against Escherichia coli(E.coli),Methicillin-resistant Staphylococcus aureus(MRSA)and Staphylococcus aureus(SA)in vitro were also evaluated.The results showed that these two compounds had no obvious anti-microbial activities.ConclusionFour new stilbene derivatives with aldehyde group were isolated from the leaves of C.cajan for the first time,the new compounds SD-1 and SD-2 showed selective cell growth inhibitory activities against MCF-7 cell line with IC50 values as 86.6±7.5 μM and 77.6±0.3 μM.Part Two Studies on chemical constituents from the flowers of Syzygium jambos and their bioactivitiesS.jambos is a plant of Syzygium in Myrtaceae family.It is mainly contains flavonoids,terpenoids,phenols and other compounds.Modern pharmacological studies have shown that S.jambos posses antioxidant,antimicrobial,anti-inflammatory and anti-biotic properties.At present,domestic and foreign researches mainly focuses on the ethanol extract of leaves and stems of S.jambos and their biological acti vities,but the research on the flower of S.jambos have never been reported.Therefore,we carry out the studies on the chemical constituents from the flowers of S.jambos and their bioactivities.ObjectiveTo obtain new compounds with promising bioactivities in n-hexane and ethyl acetate extracts of the ethanol extract from the flowers of S.jambos.MethodsIsolation of compounds in n-hexane and ethyl acetate extracts of S.jambos was carried out by means of normal-phase and reversed-phase column chromatographies with silica gel,ODS,and sephadex as stationary phases,and high performance liquid chromatography(HPLC),as well as recrystallization.The chemical structures were identified by analysis of spectroscopic data of NMR(1H-1H COSY,HMQC,HMBC),IR,UV,and MS including HR-ESI-MS.ResultsSixteen compounds were isolated by various separation methods,and their structures were identified by spectroscopic evidences from NMR,IR,UV,and MS.They are ginkgolic acid(SPT-1),ginkgo phenol(SPT-2),(17:2)-pelandjuaic acid(SPT-3),ginkgo phenol(SPT-4),anacardic acid(SPT-5),β-sitosterol(SPT-6),ferruginol(SPT-7),uvaol(SPT-8),ursolic aldehyd e(SPT-9),ethyl linoleate(SPT-10),methyl linoleate(SPT-11),ethyl oct adec-(13Z)-enoate(SPT-12),obtusol(SPT-13),β-si tostenone(SPT-14),28-nor-urs-12-ene-3β,17β-diol’ s(SPT-15),crassifol(SPT-16).ConclusionCompounds SPT-1 to SPT-16 were isolated from the S.jambos for the first time,All of these isolated compounds were mainly ginkgolic acids,ginkgo phenols,steroids,terpenoids,and fatty acids.