Study On The Chemical Constituents Of Garcinia Xanthoymus

The ethyl acetate extract from the leaves of G.xanthochymus has been studied systematically,fifteen compounds were isolated and identified as 5,7,4'-trihydroxy-6-(3-hydroxy-3-methylbutyl)-flavone(1),1,5-dihydroxy-3-methoxy xanthone(2),1,3-dimethoxy-5-hydroxyxanthone(3),kaempferol(4),(2s,3s)-trans-dihydrokaem pferol(5),3,24,25-trihydroxytirucall-7-ene(6),4-hydroxycinnamic acid(7),isovanillic acid(8),(Z)-2-(2,4-dihydroxy-2,6,6-trimethylcyclohexylidene)acetic acid(9),volkensiflavone(10),morelloflavone(11),3,8''-biapigenin(12),bilobetin(13),fukugiside(14),GB2 a glucoside(15).Compound 1 is a new compound,5,6,9 and 13 are isolated from the genus Garcinia for the first time,4,7,8,10,11,12,14 and 15 are firstly found from this plant.Twenty one compounds were isolated from the bark of G.xanthochymus,and identified as Cyclo-(Val-Ala-Leu-3-methyl-2-hydroxylvaleric acid)(16),1,2,5-trihydroxyxanthone(17),1,5-dihydroxy-3-methoxyxanthone(18),2,5-dihydroxy-1-methoxyxanthone(19),Garcinenone J(20),12b-hydroxy-des-D-garcigerin(21),Symphoxanthone(22),1,3,5,6-tetrahydroxy-8-(3-methylbut-2-enyl)xanthone(23),1,4,6-trihydroxy-5-methoxy-7-(3-methylbut-2-enyl)xanthone(24),1,3,5-trihydroxy-4-(3-methylbut-2-enyl)-9H-xanthen-9-one(25),6-Deoxyjacareubin(26),Atroviridin(27),1,4-dihydroxy-5-methoxy-6?,6?-dimethylpyrano(2?,3?:6,7)xanthone(28),Garcinenone A(29),1,2,5,6-tretrahydroxy-4-(1,1-dimethy-2-propenyl)-7-(3-methyl-2-butenyl)xanthone(30),1,4,5,6-tetrahydroxy-7,8-di(3-methylbut-2-enyl)xanthone(31),1,5,6-trihydroxy-7,8-di(3-methyl-2-butenyl)-6',6'-dimethylpyrano(2',3':3,4)xanthone(32),1,3,5,6-tetrahydroxy-4,7,8-tri(3-methyl-2-butenyl)xanthone(33),1,3,5,6-tetrahydroxy-7-geranylxanthone(34),Garcinenone D(35),1,3,5,6-tetrahy droxy-4,7-di-(3-methyl-2-butenyl)-8-(3-hydroxy-3-methylbutyl)xanthone(36).Compound 16 is a new compound,17,18,25,26,27 and 28 are firstly found from this plant.Antitumor and antidiabetic activities of compounds from G.xanthochymus have been investigated.Compound 13(bilobetin)showed moderate inhibitory activities against ?-amylase with IC50 value of 8.12 ?M,compound 33(1,3,5,6-tetrahydroxy-4,7,8-tri-(3-methyl-2-butenyl)xanthone)exhibited significant cytotoxic activity against SGC7901,Hep G2 and MCF-7 cell line with IC50 values of 0.08,4.15 and 2.38 ?M respectively,which were better than those of doxorubicin.The determination method of biflavones from the leaves of G.xanthochymus was establishded by accuracy,precision,stability and recovery.The concentration of biflavones and the chromatographic peak areas showed high precision,the correlation coefficient of regression equation were great than 0.999.The determination method has high precision,good reproducibility and stability,the recovery of fukugetin and fukugiside were 100.07% and 99.32%.The stability,precision and recovery reached the drug analysis requirements.