Antibacterial xanthones from the leaves of Garcinia nigrolineata

Ten new 1,3,5-trioxygenated xanthones, nigrolineaxanthones J-S (1-10), one new quinone derivative, nigrolineaquinone A (11), and one new isoflavone-like compound, nigrolineaisoflavone A (12), were isolated from the leaves of Garcinia nigrolineata along with four known xanthones and friedelin. Among the xanthones, only nigrolineaxanthone N (5) showed significant antibacterial activity against methicillin-resistant Staphylococcus aureus.     

Inhibitory Activities of Compounds from the Twigs of Garcinia hombroniana Pierre on Human Low‐density Lipoprotein (LDL) Oxidation and Platelet Aggregation

The methanol extract of the twigs of Garcinia hombroniana, which showed strong LDL antioxidation and antiplatelet aggregation activities, was subjected to column chromatography to obtain 3,5,3′,5′‐tetrahydroxy‐4‐methoxybenzophenone, 1,7‐dihydroxyxanthone and eight triterpenoids, garcihombronane B, D, E and F, friedelin, glutin‐5‐en‐3β‐ol, stigmasterol and lupeol. The structures of the compounds were elucidated by spectroscopic methods. The compounds were evaluated for their ability to inhibit copper‐mediated LDL oxidation and arachidonic acid (AA)‐, adenosine diphosphate (ADP)‐, collagen‐induced platelet aggregation in vitro. Among the compounds tested, 3,5,3′,5′‐tetrahydroxy‐4‐methoxybenzophenone and 1,7‐dihydroxyxanthone showed strong inhibitory activity on LDL oxidation with half‐maximal inhibitory concentration (IC₅₀) values of 6.6 and 1.7 µm , respectively. 3,5,3′,5′‐Tetrahydroxy‐4‐methoxybenzophenone exhibited strong activity on AA‐, ADP‐ and collagen‐induced platelet aggregation with IC₅₀ values of 53.6, 125.7 and 178.6 µm , respectively, while 1,7 dihydroxyxanthone showed significant and selective inhibitory activity against ADP‐induced aggregation with IC₅₀ value of 5.7 µm . Of the triterpenoids tested, garcihombronane B showed moderate activity against LDL oxidation and garcihombronane D and F showed selective inhibition on ADP‐induced platelet aggregation. Copyright © 2012 John Wiley & Sons, Ltd.     

Antibacterial activity of two biflavonoids from Garcinia livingstonei leaves against Mycobacterium smegmatis

Amentoflavone and 4′ monomethoxy amentoflavone were previously isolated from Garcinia livingstonei leaves. These compounds had good activities (MIC 6 and 8 μg/ml) against some nosocomial bacteria. In this study, the activity of these purified compounds were tested against fast-growing non-pathogenic Mycobacterium smegmatis. Amentoflavone was the most active compound, with an MIC of 0.60 ± 0.70 mg/ml. The MIC of 4′ monomethoxy amentoflavone and the positive control isoniazid against Mycobacterium smegmatis were similar 1.40 ± 1.56 and 1.30 ± 1.70 mg/ml respectively. Although, Mycobacterium smegmatis is a non-pathogenic fast growing mycobacterium the activities of these compounds may also be useful in combating infections by pathogenic Mycobacterium spp.     

Anti-inflammatory effects of hydroalcoholic extract and two biflavonoids from Garcinia gardneriana leaves in mouse paw oedema

Garcinia gardneriana (Planch. & Triana) Zappi (Clusiaceae) is widely distributed in Brazil and used in folk medicine to treat inflammation, pain, and urinary tract and other infections. However, very few studies have analyzed these therapeutic effects. In this study, the anti-inflammatory effects of the hydroalcoholic extracts from Garcinia gardneriana (HEGG) and some of its isolated biflavonoids were evaluated. The results showed that HEGG from the leaves, bark and seeds reduced carrageenan-induced mouse paw inflammation, in addition to diminishing the myeloperoxidase activity in the stimulated tissues. The reduction of neutrophil infiltration by treatment with the HEGG from leaves was confirmed by histology. The leaf extract also reduced the paw oedema evoked by bradykinin, histamine, prostaglandin E2 and 12-O-tetradecanoylphorbol acetate. However, it partially decreased substance P and compound 48/80-caused paw oedema, without any influence on the arachidonic acid-induced oedema. Both of the isolated compounds, fukugetin and GB-2a, prevented the carrageenan-induced paw oedema. In conclusion, this study showed important anti-inflammatory effects of HEGG through its interaction with different intracellular signaling pathways, without interfering with the formation of arachidonic acid (AA) metabolites. These characteristics, in addition to the wide distribution and culturing ease of the plant, confirm its popular use and highlight its promise in the development of new anti-inflammatory drugs.     

Xanthones from Garcinia parvifolia

Nine new xanthones, parvixanthones A-I (1-9), isolated from the dried bark of Garcinia parvifolia, were found to have a common 1,3,6,7-oxygenated pattern for their xanthone nucleus, but various oxygenated isoprenyl or geranyl substituent groups. The structures were determined by spectroscopic methods.     

岭南山竹子叶三萜成分研究

目的 研究岭南山竹子叶的化学成分.方法 利用正相硅胶、葡聚糖凝胶Sephadex LH-20等手段进行分离纯化,根据波谱数据鉴定化合物的结构.结果 分离鉴定了5个三萜类成分,其结构分别是:5 (6)-gluten-3α-ol(1),24-Methylenecycloart-3-one(2),木栓酮(3),表木栓醇(4),熊果酸(5).结论 均为首次从该种植物中分离得到.     

Xanthones and benzophenones from the stems of Garcinia multiflora

Two new xanthone derivatives, garcinianones A (1) and B (2), two new benzophenone derivatives, 4,6,4'-trihydroxy-2,3'-dimethoxy-3-prenylbenzophenone (3) and 4,6,3',4'-tetrahydroxy-2-methoxybenzophenone (4), and a new inseparable mixture of (1E,22Z)-1,22-diferuloyloxydocosane and (1E,24Z)-1,24-diferuloyloxyteracosane (5), together with the previously known 3,8-dihydroxy-2,4,6-trimethoxyxanthone, 6,3'-dihydroxy-2,4-dimethoxybenzophenone, maclurin (6), 2,4,6,3'-tetrahydroxybenzophenone (7), and naringenin, were isolated from the stems of Garcinia multiflora. The structures of 1-5 were elucidated by extensive analysis of their spectral data. Compounds were evaluated in the brine shrimp lethality test and in the DPPH antioxidant assay.     

版纳藤黄果实的化学成分

目的：研究版纳藤黄Garcinia xipshuanbannaensis果实的化学成分.方法：利用硅胶柱色谱和Sephadex LH-20柱色谱分离版纳藤黄果实的化学成分，通过波谱技术鉴定化舍物的结构。结果：从该植物果实的乙醇提取物中分离并鉴定了12个化合物，其结构分别为tovophyllinB（Ⅰ），β-谷甾醇（Ⅱ），熊果酸（Ⅲ），1-十八醇（Ⅳ），isogarcinol（Ⅴ），3’，5，7-三羟基-4’-甲氧基黄酮（Ⅵ），木犀草素（Ⅶ），luteolin-7—O-glucuroaic acid methylester（Ⅷ），胡萝卜亭（Ⅸ），牡荆苷（Ⅹ），β-D-吡喃阿拉伯糖（Ⅺ），蔗糖（Ⅻ）。结论：化合物Ⅰ、Ⅲ～Ⅺ为首次从该种植物中得到.     

Cytotoxic prenylxanthones from Garcinia bracteata

Bioassay-guided fractionation of a leaf extract of G. bracteata has yielded six new prenylxanthones, bractatin (1), isobractatin (2), 1-O-methylbractatin (3), 1-O-methylisobractatin (4), 1-O-methyl-8-methoxy-8,8a-dihydrobractatin (5), and 1-O-methylneobractatin (6). The structures of these compounds have been elucidated by spectroscopic means (NMR, MS), literature data, and X-ray crystallographic analysis of 2. These compounds possess significant cytotoxicity against the KB cell line.     

Antioxidant xanthones from Garcinia vieillardii

Two new xanthones, 6-O-methyl-2-deprenylrheediaxanthone B (1) and vieillardixanthone (2), were isolated from the stem bark of Garcinia vieillardii, as were four known compounds (4-7). The structures of 1 and 2 were determined by means of spectroscopic analysis and chemical derivatization. Each isolate was tested for its antioxidant properties based on a scavenging activity study using the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical.     

Anti-inflammatory phloroglucinols and terpenoids from Garcinia subelliptica

Three new phloroglucinols, garcinielliptones K (1), L (2), and M (3), and two new terpenoids, garcinielliptones N (4) and O (5), have been isolated from the seeds of Garcinia subelliptica. The structures of 1-5 including their relative configurations were elucidated by spectroscopic methods and supported by computer-generated molecular modeling. Compounds 2 and 3 showed potent inhibitory effects on the release of beta-glucuronidase, and on beta-glucuronidase and histamine, respectively, from peritoneal mast cells stimulated with p-methoxy-N-methylphenethylamine (compound 48/80) in a concentration-dependent manner. Compounds 2 and 3 showed potent effects on NO production in culture media of RAW 264.7 cells in response to lipopolysaccharide (LPS). Compound 2 also showed a potent effect on NO production in culture media of N9 cells in response to LPS/interferon-gamma (IFN-gamma).     

Caged-triprenylated and -tetraprenylated xanthones from the latex of Garcinia scortechinii

The latex of Garcinia scortechinii has yielded eight new caged-polyprenylated xanthones: two triprenylated (1 and 2) and five tetraprenylated xanthones (3-7) and one degraded caged-tetraprenylated xanthone (8), together with the known scortechinones A (9) and B (10). Their structures were elucidated by analysis of spectroscopic data and comparison of the NMR data with those reported previously.     

Xanthone and sesquiterpene derivatives from the fruits of Garcinia scortechinii

The fruits of Garcinia scortechinii afforded 10 new compounds: four caged-tetraprenylated xanthones (scortechinones Q-T, 1-4), four rearranged xanthones (scortechinones U-X, 5-8), and two sesquiterpene derivatives (scortechterpenes A, B, 9, 10), together with 14 known compounds: one sesquiterpene, two biflavonoids, and 11 caged-polyprenylated xanthones. Their structures were elucidated by analysis of spectroscopic data and comparison of the NMR data with those reported previously. All xanthone derivatives were evaluated for antibacterial activity against methicillin-resistant Staphylococcus aureus.     

Xanthones from the green fruit hulls of Garcinia mangostana

Three new xanthones, mangostenol (1), mangostenone A (2), and mangostenone B (3), were isolated from the green fruit hulls of Garcinia mangostana, along with the known xanthones, trapezifolixanthone, tovophyllin B (4), alpha- and beta-mangostins, garcinone B, mangostinone, mangostanol, and the flavonoid epicatechin. The structures of the new xanthones were elucidated by analysis of their spectroscopic data.     

Cytotoxic prenylated depsidones from Garcinia parvifolia

Leaf extracts of Garcinia parvifolia provided relatively high yields of four novel, cytotoxic prenylated depsidones. The structures were determined mainly by detailed NMR spectral analysis and X-ray crystallography.     

Bioactive benzophenones from Garcinia xanthochymus fruits

A MeOH extract of Garcinia xanthochymus fruits was subjected to activity-guided fractionation, yielding two new benzophenones, guttiferone H (1) and gambogenone (2). Compound 1 contains a seven-membered ring attached to the bicyclo[3.3.1]nonane system at positions 7 and 8 and displayed cytotoxicity in the SW-480 colon cancer cell line (IC(50) = 12 microM). Compound 2 has a novel benzophenone bicyclo[3.3.2]decane system and displayed cytotoxicity in the SW-480 colon cancer cell line (IC(50) = 188 microM). Both 1 and 2 induced apoptosis in SW-480 colon cancer cells and displayed antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay (IC(50) = 64 and 38.7 microM, respectively). The structures of 1 and 2 were established by 1D and 2D NMR data analysis. Eleven known compounds, aristophenone A, alloathyriol, amentoflavone, 3,8' '-biapigenin, cycloxanthochymol, (+/-)-fukugetin, (+/-)-fukugiside, guttiferone E, isoxanthochymol, (+/-)-volkensiflavone, and xanthochymol, were also obtained. The 11 known compounds were also tested against SW-480 colon cancer cells and in the DPPH assay.     

双籽藤黄茎皮化学成分的研究

目的：研究双籽藤黄Garcinia tetralata茎皮的化学成分。方法：采用硅胶、ODS柱色谱等方法进行分离纯化，根据理化性质及波谱数据鉴定化合物的结构。结果：从双籽藤黄95%乙醇提取物的氯仿萃取层中分离得到10个化合物，分别鉴定为1,7-二羟基酮(1)，buchanaxanthone(2)，garciniaxanthone H(3)，1,2,5-三羟基酮(4)，subelliptenone H(5)，6-deoxyisojacreubin(6)，6-deoxyjacreubin(7)，subelliptenone G(8)，苔色酸甲酯(9)和β-谷甾醇(10)。结论：化合物1～10均为首次从该种植物中分离得到，化合物9为首次从该属植物中分离得到。     

云南山竹子果实的化学成分研究

 目的分离和鉴定云南山竹子(Garcinia cowa)果实的化学成分。方法体积分数为95%乙醇提取,用硅胶柱色谱和凝胶柱(LH-20)色谱分析,采用IR,NMR,MS等谱学方法及化学方法确定结构。结果分得6个化合物,经光谱数据的分析,分别鉴定为β-谷甾醇(Ⅰ),cirsiumaldehyde(Ⅱ),对羟基桂皮酸(Ⅲ),穗花杉双黄酮(Ⅳ),胡萝卜苷(Ⅴ),morelloflavone(Ⅵ)。结论化合物Ⅰ～Ⅵ系首次从该种植物中分离得到。     

Three xanthones and a benzophenone from Garcinia mangostana

Investigation of the constituents of Garcinia mangostana has led to the isolation of four new compounds: three minor xanthones, garcimangosone A (1), garcimangosone B (2), and garcimangosone C (3), and a benzophenone glucoside, garcimangosone D (4). The structures of these four compounds were established by spectral (NMR and MS) and chemical methods.     

Trypanocidal and antileishmanial dihydrochelerythrine derivatives from Garcinia lucida

Three benzo[ c]phenanthridine alkaloids have been isolated from the stem bark of Garcinia lucida: dihydrochelerythrine ( 1), 6-acetonyldihydrochelerythrine ( 2), and its new derivative, ( S)1'-(9,10-dihydro-2',3'-dihydroxy-7,8-dimethoxy-10-methyl-1,2-benzophenanthridin-9-yl)propan-2'-one (lucidamine A) ( 3). The new diisoprenylated derivative of lucidamine B ( 4) was obtained by semisynthesis. These dihydrochelerythrine derivatives as well as the crude extract displayed attractive antiprotozoal activity against Trypanosoma brucei brucei and Leishmania donovani, with little toxicity to Vero cells and the host cells. This is the first trypanocidal and antileishmanial bioguided study of G. lucida, and the activity of the crude extract as well as of the dihydrochelerythrine derivatives are reported for the first time.