蔓性千斤拔化学成分的研究

从豆科植物蔓性千斤拔[Flemingia philippinensis(Merr.et Rolfe)Li]的根中分得六个化合物和一个烷酸的混合物(Ⅰ～Ⅶ)。经理化常数测定和光谱分析证明,化合物Ⅰ和Ⅱ为新化合物,分别命名为蔓性千斤拔素C(Ⅰ)和蔓性千斤拔素D(Ⅱ),其余为已知物,分别鉴定为5,7,3′,4′-四羟基-6,8-双异戊烯基异黄酮(Ⅲ),flemichin D(Ⅳ),n C₂₂～C₃₀烷酸(Ⅴ),β-谷甾醇(Ⅵ)和羽扇豆醇(Ⅶ)。化合物Ⅲ和Ⅳ对P₃₈₈白血病细胞具有显著的抑制作用。     

粉枝莓中的两种新黄酮成分

为研究粉枝莓(Rubus biflorus Buch)的化学成分，经柱色谱分离，从粉枝莓中分离得到2个黄酮类化合物，光谱分析鉴定其结构为：8-甲基-6-异戊烯基-5,7-二羟基-5′-甲氧基-3′,4′-二氧亚甲基黄酮(A),和8-甲基-5′-异戊烯基-5-甲氧基-6,7-(2″,2″-二甲基吡喃)-3′,4′-二氧亚甲基黄酮(B)，分别命名为粉枝莓素A和粉枝莓素B。化合物A和B为新的黄酮类化合物。     

Nigerasperones A approximately C, new monomeric and dimeric naphtho-gamma-pyrones from a marine alga-derived endophytic fungus Aspergillus niger EN-13

Three new naphtho-gamma-pyrones, 5-hydroxy-6,8-dimethoxy-2-hydroxymethyl-4H-naphtho[2,3-b]pyran-4-one (1, nigerasperone A), 3,3'-dihydro-2,2',5,5'-tetrahy-droxy-8,8',10,10'- tetramethoxy-2,2'-dimethyl-(6',9-bi-4H-naphtho[1,2-b]pyran)-4,4'-dione (2, nigerasperone B), and 3'-hydro-2',5,5',8-tetrahydroxy-6,6',8'-trimethoxy-2,2'-dimethyl-(7,10'-bi-4H-naphtho[2,3-b]pyran)-4,4'-dione (3, nigerasperone C), together with nine related known compounds were characterized from Aspergillus niger EN-13, an endophytic fungus isolated from the marine brown alga Colpomenia sinuosa. Their structures were elucidated by detailed analysis of spectroscopic data and by comparison with literature reports. In the cytotoxic assay, these compounds did not show remarkable inhibitory effects against A549 and SMMC-7721 tumor cell lines. However, 3 and several known compounds showed weak antifungal activity against Candida albicans and moderate activity on DPPH scavenging.     

白花败酱草化学成分的分离与结构鉴定

目的研究白花败酱草的化学成分。方法利用溶剂萃取后进行硅胶柱和制备液相色谱分离纯化，根据理化性质和光谱数据鉴定结构。结果分离并鉴定了8个化合物：bolusanthol B (1)，(2S)-5,7,2′,6′-四羟基-6,8-二异戊烯基-二氢黄酮(2)，orotinin (3)，(2S)-5,7,2′,6′-四羟基-6-lavandulyl-二氢黄酮(4)，3′-异戊烯基-芹黄素(5)，木犀草素(6)，槲皮素(7)和洋芹素(8)。结论化合物2，4为新化合物，1，3，5为首次从败酱属植物中分离得到，6，7，8为首次从白花败酱草中分离得到。     

9, 10-Dihydrophenanthrene derivatives from Pholidota yunnanensis and scavenging activity on DPPH free radical

Three new 9,10-dihydrophenanthrene derivatives named phoyunnanins A-C, together with six known 9,10-dihydrophenanthrene constituents, 4,4',7,7'-tetrahydroxy-2,2'-dimethoxy-9,9',10,10'-tetrahydro-1,1'-biphenanthrene (4), lusianthridin (5), eulophiol (6), 2,4,7-trihydroxy-9,10-dihydrophenanthrene (7) and imbricatin (8), were isolated from the 60% ethanolic extract of air-dried whole plant of Pholidota yunnanensis Rolfe. The structures of phoyunnanins A-C were established as 6-[2'-(3',3'-dihydroxy-5'-methoxybibenzy)]-4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (1), 6-[6'-(trans-3',3'-dihydroxy-5'-methoxystilbeny)]-4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (2) and 4,4',7,7'-tetrahydroxy-2,2'-dimethoxy-9,9',10,10'-tetrahydro-1,6'-biphenanthrene (3), respectively, on the basis of the spectroscopic analysis. All eight compounds (1-8) were found to show the DPPH free radical scavenging activity with EC₅₀ from 8.8 to 55.9 μM.     

New flavonoids and other constituents from Lespedeza cuneata

Two new flavonoids, 6,8,3',4'-tetrahydroxy-2'-methoxy-7-methylisoflavanone (1) and 6,8,3',4'-tetrahydroxy-2'-methoxy-6'-(1,1-dimethylallyl)-isoflavone (2), were isolated from the 95% ethanolic extract of the dried roots of Lespedeza cuneata together with betulinic acid (3), beta-sitosterol (4), hexacosanoic acid 2,3-dihydroxy-propyl ester (5), which were isolated from this plant for the first time. Their structures were elucidated by spectral analysis.     

Simple indole alkaloids from the neotropical rutaceous tree Raputia simulans

The genus Raputia Aubl. comprises 10 neotropical species of the family Rutaceae belonging to the subtribe Cuspariinae. We report herein the investigation of the dichloromethane extract of the stem bark of R. simulans, which has led to the isolation of indole type alkaloids. The isolation procedure was performed by fast centrifugal partition chromatography (FCPC) and adsorption chromatography and afforded 11 isolates: indole-5-carbaldehyde (1), 7-prenylindole (2), 5-prenylindole (3), verticillatine B (4), 5-(but-3'-en-2'-one)indole (5), 5-(2'-methylbut-3'-en-1'-ol)indole (6), 5-[methyl-4'-(2'-methyl-4-oxobutanoate)]indole (7), 5-[4-(methyl)furan-2-yl]indole ( 8), 5-[4-(methoxymethyl)furan-2-yl]indole (9), 5-[5'-(3-methylfuran-2'(5' H)-one)]indole (10), and 5-(4'-methyl-2',5'-dihydrofuran-2'-yl)indole (11). Metabolites 5- 11 were isolated for the first time and bear uncommon substituents on position 5 of the indole moiety.     

Further acylated chalcones from Bidens pilosa

Three new acylated chalcone glucosides [okanin 4'- O-beta- D-(4'-acetyl-6'- TRANS- P-coumaroyl)-glucoside, okanin 4'- O-beta- D-(2',4'-diacetyl-6'- TRANS- P-coumaroyl)-glucoside, and okanin 4'- O-beta- D-(3',4'-diacetyl-6'- TRANS- P-coumaroyl)-glucoside] have been isolated from the leaves of BIDENS PILOSA L. (Asteraceae). Their structures have been elucidated by spectroscopic methods ( (1)H-NMR, 2D- (1)H-NMR, (13)C-NMR spectroscopy).     

New flavonoids and other constituents from Lespedeza cuneata

Two new flavonoids, 6,8,3',4'-tetrahydroxy-2'-methoxy-7-methylisoflavanone (1) and 6,8,3',4'-tetrahydroxy-2'-methoxy-6'-(1,1-dimethylallyl)-isoflavone (2), were isolated from the 95% ethanolic extract of the dried roots of Lespedeza cuneata together with betulinic acid (3), β-sitosterol (4), hexacosanoic acid 2,3-dihydroxy-propyl ester (5), which were isolated from this plant for the first time. Their structures were elucidated by spectral analysis.     

显脉羊蹄甲的生物活性成分

目的对显脉羊蹄甲中具有抑制血小板聚集活性的有效部位的化学成分进行研究。方法从显脉羊蹄甲抑制血小板聚集活性部位中,利用溶剂分步萃取法和各种色谱手段(硅胶吸附柱色谱,聚酰胺柱色谱,Sephadex LH-20柱色谱,开放ODS柱色谱,液相色谱等)分离得到了10个化合物,根据其理化性质和光谱数据分析(1H-NMR、13C-NMR等)鉴定了它们的结构。结果从活性部位中分离鉴定的化合物为黄酮类,分别是:3,5,7,4'-四羟基-3'-甲氧基黄酮(3,5,7,4'-tetrahydroxy-3'-methoxyflavone,1)、5,7,3',4'-四羟基-3-甲氧基黄酮(5,7,3',4'-tetrahydroxy-3-methoxyflavone,2)、槲皮素(quercetin,3)、木樨草素(luteolin,4)、山柰酚(kaempferol,5)、5,7,4'-三羟基-3'-甲氧基黄酮(5,7,4'-trihydroxy-3'-methoxyflavone,6)、7,3',4'-三羟基-3-甲氧基黄酮(7,3',4'-trihydroxy-3-methoxyflavone,7)、杨梅苷(myricitrin,8)、槲皮素-3-O-α-L-吡喃阿拉伯糖苷(quercetin-3-O-α-Larabinopyranoside,9)、儿茶素(catechin,10)。结论化合物1-6、8-9均为首次从该植物中分离得到,化合物7为首次从羊蹄甲属植物中分离得到。     

Dihydrochalcones from Piper longicaudatum

Bioactivity-guided fractionation of an ethanolic extract of the leaves and twigs of Piper longicaudatum Trelease & Yunker (Piperaceae) resulted in the isolation of one new (1) and three known (2-4) dihydrochalcones. The known compounds are: 2',6'-dihydroxy-4'-methoxydihydrochalcone (2), 2',6',4-trihydroxy-4'-methoxydihydrochalcone (asebogenin) (3), and 2'-hydroxy-4'-methoxy-2'-[1-hydroxy-1-methylethyl]-2",3"-dihy- drofurano[4",5":5',6"]-3"-[2-hydroxy-5-methoxycarbonylphe- nyl]dihydrochalcone (piperaduncin B) (4). The new compound is 2'-hydroxy-4'-methoxy-2"-[2-hydroxy-5-methoxycarbonyl- phenyl]-furano[4",5":5',6']-dihydrochalcone (longicaudatin) (1). Compounds 1-4 were tested for antibacterial activity against S. aureus and methicillin-resistant S. aureus (MRSA); only compound 3 showed inhibitory activity (IC50 of 10 and 4.5 micrograms/ml, respectively).     

Antimicrobial prenylated acetophenones from berries of Harrisonia abyssinica

The ripe berries of Harrisonia abyssinica yielded two new prenylated acetophenones, namely 5-(ethan-1'-one)-4,6-dihydroxy-7-(3',3'-dimethylallyl)-2 S-(1' S-hydroxy-1',5'-dimethylhex-4'-enyl)-2,3-dihydrobenzofuran (1) and 5-(2'-hydroxyethan-1'-one)-4,6-dihydroxy-7-(3',3'-dimethylallyl)-2 S-(1' S-hydroxy-1',5'-dimethylhex-4'-enyl)-2,3-dihydrobenzofuran (2), herein named harronin I and harronin II, respectively. The compounds were isolated following activity guided fractionation and the structures were determined using 1D, 2D NMR spectroscopic, CD and MS spectrometric techniques. The methanol-dichloromethane mixture (1 : 1 v/v) crude extract exhibited strong antimicrobial activity against Candida albicans, Bacillus cereus, Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Lactobacillus casei. Harronin I (1) showed a MIC of 5 μg/mL against C. albicans, 6 μg/mL against B. cereus, and more than 20 μg/mL against other tested microorganisms. Harronin II (2) showed much weaker MIC values (> 100 μg/mL) against all the tested microorganisms.     

黄杉化学成分的研究

目的研究黄杉的化学成分。方法用色谱方法分离黄杉化学成分,用波谱技术(IR,UV,MS,1D和2D-NMR)鉴定结构。结果从黄杉树皮中分离得到6个化合物,分别鉴定为5,7,4′-trihydroxy-6-methylflavanone (poriol, I), 3,5,7,3′,4′-pentahydroxyflavonone (quercetin, II), 5,7,3′,5′-tetrahydroxy-6-methylflavanone (III), 5,7,3′,5′-tetrahydroxyflavanone (IV), 3,5,7,3′,5′-pentahydroxyflavanone (V)和5-hydroxy-6-methylchromone-7-O-β-D-glucopyranoside (VI)。结论III,VI为新化合物,所得6个化合物均为首次从该属植物中分得。     

中间锦鸡儿黄酮类成分的研究

目的研究中间锦鸡儿的化学成分。方法用溶剂法、色谱法分离化学成分，用波谱法鉴定其结构。结果从中间锦鸡儿中分离得到10个黄酮类化合物，分别鉴定为5,7,4′-三羟基-3,3′-二甲氧基黄酮(1)，3,5,7,8,4′-五羟基-3′-甲氧基黄酮(2),槲皮素(3),柠檬黄酮醇(4),槲皮素-3-甲醚(5)，2(S)-7,3′,5′-三羟基二氢黄酮(6)，5,7,3′,4′-四羟基-3,8-二甲氧基黄酮(7),紫铆查尔酮（8）,甘草素（9）和5,7,4′-三羟基-3,8二甲氧基黄酮（10）。结论化合物6为新化合物，其余皆首次从中间锦鸡儿中分离得到。     

Acetophenone derivatives and sesquiterpene from Euphorbia ebracteolata

Two new acetophenone derivatives and a new sesquiterpene, along with four known acetophenone compounds, were isolated from the roots of Euphorbia ebracteolata. The structures of the new compounds were identified as 2,2',4,4'-tetrahydroxy-6,6'-dimethoxy-3,3'-dimethyl-7,5'-bisacetophenone, 2,4-dihydroxy-6-methoxy-3-methylacetophenone 4-O-alpha-L-arabinofuranosyl-(1-->6)-beta- D-glucopyranoside and decahydro-1a,4a,7,7-tetramethyl-1H-cycloprop[e]azulene-2,5-diol (1a R,2 R,4a S,5 S,7a R,7b R) using 1D and 2D NMR spectroscopy and X-ray crystallography.     

New prenylchalcones from the hops of Humulus lupulus

Two new prenylchalcones, xanthohumol C and D, together with two known prenylchalcone derivatives, xanthohumol (1) and 5'-(2'-hydroxyisopropyl)-dihydrofurano-[2',3'-b]-4,4'-dihydroxy-6'-methoxy-chalcone (4) were isolated and identified from the hops of Humulus lupulus L. The structures of xanhohumol C and D were elucidated as 5'-hydroxy-6',6'-dimethyl-dihydropyrano-[2',3'-b]-4,4'-dihydroxy-6'-methoxy-chalcone (2) and 5'-hydroxy-6',6'-dimethyl-dihydropyrano-[2',3'-b]-4',6'-dimethoxy-4-hydroxy-chalcone (3) on the basis of HRFAB-MS, 1D and 2D NMR (HMQC, HMBC) spectroscopic data. Among the new prenylchalcones, compound 2 showed marginal cytotoxic activity against human stomach carcinoma BGC-823 and human hepatic carcinoma HepG2 cells.     

Identification and stability of a new bichalcone in Achyrocline satureioides spray dried powder

A new chemical structure, the 4,2',4",2'-tetrahydroxy-6',6'-dimethoxy-4'-O-4'- bichalcone, named achyrobichalcone was isolated and identified from an Achyrocline satureioides spray-dried powder (SDP80). The thermal and photo stability of this new compound as well as that of the main polyphenols present in the spray dried powder, quercetin, luteolin, 3-O-metylquercetin and the corresponding kinetics of degradation are reported. In the long-term testing (30 +/- 2 degrees C/75 +/- 5% RH, 12 months), the total polyphenols contained in SDP80 demonstrated to be stable, remaining higher than 90% after a 12 month exposure. The photo stability testing revealed that all polyphenols were stable for 48 h when SDP80 was conditioned in amber or transparent flasks and exposed to UV-C radiation (light express LE UV, 254 nm, 30W). In contrast, when unprotected, the polyphenols demonstrated to be sensitive to both, thermal stress testing (80 +/- 2 degrees C), for 14 days and to UV-C radiation. Luteolin showed to be the most stable against UVC light and 3-O-methylquercetin against temperature. The achyrobichalcone demonstrated to be the more unstable against both, temperature and light. The kinetics of polyphenol thermal degradation (80 +/- 2 degrees C, 49 days) and photodegradation (UV-C radiation, 96 h) followed, 2nd and 1st order reaction, respectively.     

New flavonol glycosides and new xanthone from Polygala japonica

Three new flavonol glycosides and a new xanthone were isolated from Polygala japonica HOUTT. with eight known compounds. Their structures were identified as 1,7-dihydroxy-3,4-dimethoxy-xanthone (1), kaempferol-7,4'-dimethyl ether (2), physcion (3), guazijinxanthone (4), rhamnetin (5), polygalin A (6), 3,5,7-trihydroxy-4'-methoxy-flavone-3-O-beta-d-galactopyranoside (7), 3,5,3'-trihydoxy-7,4'-dimethoxy-flavone-3-O-beta-d-galactopyranoside (8), 3,5,3',4'-tetrahydroxy-7-methoxy-flavone-3-O-beta-d-galactopyranoside (9), 3,5,3',4'-tetrahydroxy-7-methoxy-flavone-3-O-beta-d-glucopyranoside (10), polygalin B (11), polygalin C (12). Among them, compound 4 is a new xanthone, and 6, 11 and 12 are new flavonol glycosides. Compounds 1, 4, 7 and 8 were tested for cytotoxic activity with MTT assays on five human tumor cell lines, K562, A549, PC-3M, HCT-8 and SHG-44. Compound 4 showed cytotoxic activity against all the five cell lines.     

Antimicrobial flavonoids from Bolusanthus speciosus

A new isoflavanone namely 3,5,7,2',4'-pentahydroxy-8,3'-di(gamma,gamma-dimethylallyl)isoflavanone (bolusanthin II) and four new pterocarpans identified as 3-hydroxy-6',6'-dimethylpyrano[2',3':1,2] [6a R,11a R]-8,9-methylenedioxypterocarpan (bolucarpan A), 3-hydroxy-6',6'-dimethyl-4',5'-dihydropyrano[2',3':1,2][6a R,11a R]- 8,9-methylenedioxypterocarpan (bolucarpan B), 3-hydroxy-9-methoxy-6',6'-dimethylpyrano-[2',3':1,2][6a R,11a R]-pterocarpan (bolucarpan C) and 3-hydroxy-9-methoxy-6',6'-dimethyl-4',5'-dihydropyrano[2',3':1,2][6a R,11a R]-pterocarpan (bolucarpan D) and three known isoflavonoids were isolated from the methanolic extracts of the root bark, while eight known isoflavonoids were isolated from the stem bark of Bolusanthus speciosus. These compounds showed antimicrobial activity against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Saccharomyces cerevisiae and Candida mycoderma using the agar overlay technique.     

Anti-complement activity of norlignans and terpenes from the stem bark of Styrax japonica

A new norlignan, styraxlignolide A (1), and two new terpenes, styraxosides A (2) and B (3), were isolated from the MeOH-soluble fraction of Styrax japonica Sieb. et Zucc. (Styracaceae) stem bark, together with two known compounds, egonol (4) and masutakeside I (5). The new compounds were determined as 5-(3'-hydroxypropyl)-7-methoxy-2-(3',4'-dimethoxyphenyl)-benzofuran 3'- O-[beta-D-xylopyranoside-(1-->6)-beta- D-glucopyranoside] (1), 3beta,7beta-dihydroxy-4alpha,4beta,8beta,10beta,14alpha-pentamethyl-5alpha-gon-16-en-2-one 3-O-[beta-D-glucopyranoside-(1-->2)-beta-D-glucopyranoside] (2), and 3beta,17beta-dihydroxy-28-norolean-12-en-16-one 3-O-[alpha-L-rhamopyranoside-(1-->2)-beta-D-glucuronopyranoside] (3) by spectroscopic means including 2D-NMR. The five compounds were tested in vitro for anti-complement activity against the complement system. Compounds 1, 3, 4, and 5 displayed inhibitory activity in the anti-complement assay, with IC50 values of 123, 65, 33, and 166 microM, respectively. Compound 1a and camellenodiol (3a), obtained from acid hydrolysis of 1 and 3, respectively, did not affect the hemolytic activity of human serum against sensitized erythrocytes. This shows that a sugar seems to play a role of enhancing significantly anti-complement activity.