Erymildbraedin A and B,two novel cytotoxic dimethylpyrano-isoflavones from the stem bark of Erythrina mildbraedii: evaluation of their activity toward endocrine cancer cells

Two new dimethylpyrano-isoflavones, named erymildbraedin A (4) and B (5), were isolated from the stem bark of the Cameroonian medicinal plant Erythrina mildbraedii, along with four known ones, the linear congeners, scandenone (1), erysenegalinsein M (2), 5,4′-dihydroxy-2′-methoxy-8-(3,3-dimethylallyl)-2″,2″-dimethylpyrano[5,6:6,7]isoflavone (3), and the angular isoflavone eryvarin B (6), and two other compounds, fraxidin and scoparone. Their structures were elucidated by the usual spectroscopic methods and isoflavone effects on the growth of human breast, prostate, and endometrial adenocarcinoma cells were determined. Isoflavones 1, 3, and 6 strongly inhibited the growth of all three cell lines, supporting the notion that a non-oxidized isoprenyl group at C-8 is requisite for cytotoxic activity.     

Two isoflavanones from the stem bark of Erythrina sacleuxii

From the stem bark of Erythrina sacleuxii two new isoflavanones, (R)-5,7-dihydroxy-2',4',5'-trimethoxyisoflavanone (trivial name, (R)-2,3-dihydro-7-demethylrobustigenin) and (R)-5-hydroxy-2',4',5'-trimethoxy-2",2"-dimethylpyrano[5",6":6,7]isoflavanone (trivial name, (R)-saclenone) were isolated. In addition the known compounds shinpterocarpin, 2,3-dehydrokievitone, abyssinone V, abyssinone V-4'-methyl ether, erythrinasinate and 4'-O-methylsigmoidin B were isolated. The structures were determined on the basis of spectroscopic evidence.     

A benzil and isoflavone derivatives from Derris scandens Benth

A benzil derivative: scandione, 2',2"-dihydroxy-4'-methoxy-4",5"-methylenedioxybenzil and two isoflavones: scandenal, 3'-formyl-4',5-dihydroxy-2",2"-dimethylchromeno-[6,7:5",6"]isoflavone and scanderone, 4',5-dihydroxy-3'-prenyl-2",2"-dimethylchromeno-[7,8:6",5"]isoflavone together with fifteen known compounds were isolated from the stem of D. scandens. Their structures were determined by spectroscopic methods. Radical scavenging, antibacterial and hypertensive activities of some of the compounds were investigated.     

Prenylated flavonoids from Moghania philippinensis

Five prenylated flavonoids, 8-(1,1-dimethylallyl)genistein (1), 5,7,3',4'-tetrahydroxy-2',5'-di(3-methylbut-2-enyl)isoflavone (2), 5,7,3'-trihydroxy-2'-(3-methylbut-2-enyl)-4',5'-(3,3-dimethylpyrano)isoflavone (3), (2R)-5,2',4'-trihydroxy-8,5'-di(3-methylbut-2-enyl)-6,7-(3,3-dimethylpyrano)flavanone (4a) and (2S)-5, 2', 4'-trihydroxy-8,5'-di(3-methylbut-2-enyl)-6,7-(3,3-dimethylpyrano)flavanone (4b), were isolated from the roots of Moghania philippinensis. The structures of these compounds were determined on the basis of spectroscopic and chemical means.     

Chemical constituents of the root bark of Erythrina droogmansiana

Two new compounds namely 7,4′-dihydroxy-2′-methoxy-3′-(3-methylbut-2-enyl)isoflavanone (1) and 5,7,3′-trihydroxy-8-(3-methylbut-2-enyl)-[6′′,6′′-dimethylpyrano(2′′,3′′:4′,5′)]isoflavone (4) were isolated from the root bark of Erythrina droogmansiana together with eight known compounds. Their structures were elucidated on the basis of spectroscopic analyses (1D- and 2D-NMR and ESI-HRMS) and by comparison with literature data. In addition, the correct ¹³C NMR of 5,7,2′,4′-tertahydroxy-8,5′-di-(3-metylbut-2-enyl)isoflavone (6) was assigned. The DPPH free radical scavenging properties of the isolated compounds were evaluated. Compounds 4–7 showed weak to moderate DPPH free radical scavenging activities.     

柯拉斯那沉香中2-(2-苯乙基)色酮类化学成分研究

为研究柯拉斯那(Aquilaria crassna Pierre ex Lecomte)沉香的化学成分。实验采用多种柱色谱方法从该沉香中分离得到9个2-(2-苯乙基)色酮类化合物,通过现代波谱学技术分别鉴定为6-甲氧基-2-[2-(3′-羟基-4′-甲氧基苯基)乙基]色酮(1)、5-羟基-6-甲氧基-2-[2-(3′-羟基-4′-甲氧基苯基)乙基]色酮(2)、tetrahydrochromone F(3)、6-甲氧基-2-[2-(3′-甲氧基-4′-羟基苯基)乙基]色酮(4)、6-甲氧基-7-羟基-2-[2-(4′-甲氧基苯基)乙基]色酮(5)、6,7-二甲氧基-2-[2-(3′-羟基-4′-甲氧基苯基)乙基]色酮(6)、6,7-二甲氧基-2-[2-(4′-甲氧基苯基)乙基]色酮(7)、6-羟基-2-[2-(4′-羟基苯基)乙基]色酮(8)、5-羟基-2-[2-(2′-羟基苯基)乙基]色酮(9)。化合物2、3和5～9均为首次从柯拉斯那所得沉香中分离得到。采用MTT法对单体化合物的细胞毒活性进行测试,测试结果表明,化合物1,2和4具有微弱的细胞毒活性。     

Benzofurans and another constituent from seeds of Styrax officinalis

The benzofuran constituents of the seeds of Styrax officinalis were investigated. From the hexane extract, two new constituents named 5-(3"benzoyloxypropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)-benzofuran (5) and 4-[3"-(1c-methylbutanoyloxy)propyl]-2-methoxy-(3',4'-methylenedioxyphenyl)-1a, 5b-dihydrobenzo-[3,4]-cyclobutaoxirene (6) were isolated together with four known compounds, 5-[3"-(1c-methylbutanoyloxy)propyl]-7-methoxy-2-(3',4'-dimethoxyphenyl)-benzofuran (4), 5-[3"-(1c-methylbutanoyloxy)propyl]-7- methoxy-2-(3',4'-methylenedioxyphenyl)-benzofuran (3), 5-(3"-acetoxypropyl)-7-methoxy2-(3',4'-methylenedioxphenyl)-benzofuran (2) and 5-(3"-hydroxypropyl)-7-methoxy-2-(3',4'-met hylenedioxyphenyl)-benzofuran (1). Although the compounds 1, 2, and 3 have been isolated previously from the seeds of Styrax obassia, this is the first record of their isolation from seeds of Styrax officinalis. The structures of the isolated compounds were established by 1D- and 2D-NMR (HMBC, HMQC, COSY), FABMS and high-resolution ESI FTMS.     

Three isoflav-3-enes and a 2-arylbenzofuran from the root bark of Erythrina burttii

From the root bark of Erythrina burttii three isoflav-3-enes, 7,4'-dihydroxy-2'-methoxy-6-(1",1"-dimethylallyl)isoflav-3-ene (trivial name, burttinol-A), 4'-hydroxy-2'-methoxy-2",2"-dimethylpyrano[5",6":8,7]isoflav-3-ene (trivial name, burttinol-B), 7,4'-dihydroxy-2'-methoxy-8-(3",3"-dimethylallyl)isoflav-3-ene (trivial name, burttinol-C), and 2-arylbenzofuran, 6,4'-dihydroxy-2'-methoxy-5-(1",1"-dimethylallyl)-2-arylbenzofuran (trivial name, burttinol-D) were isolated. In addition, the known compounds, abyssinone V-4'-methyl ether, bidwillol A, calopocarpin, erybraedin A, erythrabyssin II, isobavachalcone, phaseollidin and phaseollin were identified. The structures were determined on the basis of spectroscopic evidence.     

A chalcone and an isoflavone from Millettia pachycarpa seeds

Chemical examination of the seeds of Millettia pachycarpa has yielded a new prenylated isoflavone and a new prenylated chalcone in addition to the previously reported isoflavones 5-hydroxy-4′-methoxy-6″,6″-dimethylpyrano (2″,3″:7,8)isoflavone, 5,7,4′-trihydroxy-6,8-diprenylisoflavone, 5,7,3′,4′-tetrahydroxy-6,8-diprenyl-isoflavone and pomiferin.     

Homoisoflavonoids and xanthones from the tubers of wild and in vitro regenerated Ledebouria graminifolia and cytotoxic activities of some of the homoisoflavonoids

Eleven homoisoflavonoids and two xanthones were isolated and characterized from the bulbs of Ledebouria graminifolia. Five of the homoisoflavonoids are new compounds and were identified as: 5-hydroxy-7-methoxy-3-(4'-hydroxybenzyl)-4-chromanone, 5-hydroxy-6,7-dimethoxy-3-(4'-hydroxybenzyl)-4-chromanone, 5,7,8-trimethoxy-3-(4'-hydroxybenzyl)-4-chromanone, 5-hydroxy-3',4',7-trimethoxyspiro[2H-1-benzopyran-7'-bicyclo[4.2.0]octa-trien]-4-one, 5,7-dihydroxy-3',4'-dimethoxyspiro[2H-1-benzopyran-7'-bicyclo[4.2.0]octa-trien]-4-one. Structures were elucidated by extensive 1D, and 2D NMR spectroscopy and HRMS. A method for tissue culture was developed and the bulbs of mature plants were found to contain all the compounds isolated from the wild specimens of L. graminifolia.     

Dihydrocinnamic acids from Hortia badinii

Hortia badinii (Rutaceae) contains rutecarpine and hortiacine in the bark, as well as coumurrayin, methyl 3-[2-methoxy-6′, 6′-dimethylpyrano(2′,3′:3,4)phenyl]-propionate, 3-[2,6-dimethoxy-6′,6′-dimethylpyrano(2′,3′: 3,4)phenyl]-propionic acid, methyl 3-[2,6-dimethoxy-6′,6′-dimethylpyrano(2′, 3′: 3,4)phenyl]-propionate and methyl 3-[2,4-dimethoxy-3-prenylphenyl]-propionate in the wood.     

Isoflavonoids from roots of Erythrina zeyheri

Five isoflavonoids, (+/-)-7,2',4'-trihydroxy-8,3'-di(gamma,gamma-dimethylallyl)isoflavanone, (3R)-7,4'-dihydroxy-2'-methoxy-6,8-di(gamma,gamma-dimethylallyl)isoflavanone, (3R)-7,2',4'-trihydroxy-6,8-di(gamma,gamma-dimethylallyl)isoflavan, 2',4'-dihydroxy-8-gamma,gamma-dimethylallyl-2",2"-dimethylpyrano-[5,6:6,7]isoflavan and (6aS, 11aS)-3,6a-dihydroxy-9-methoxy-4,10-di(gamma,gamma-dimethylallyl)pterocarpan, along with five known compounds, were isolated from the roots of Erythrina zeyheri. Their structures were established on the basis of spectroscopic evidence, and their antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA) were estimated by determining minimum inhibitory concentrations.     

柬埔寨柯拉斯那沉香的化学成分研究

该文采用ODS、硅胶、Sephadex LH-20等柱色谱技术,对柬埔寨野生柯拉斯那沉香(Aquilaria crassna)进行了研究。结果表明:从柬埔寨柯拉斯那所产沉香的乙醇提取物中进行分离共得到了10个化合物,包括一对对映异构体(9a/9b)。经波谱解析分别鉴定为6-甲氧基-2-[2-(3-羟基-4-甲氧基苯)乙基]色酮(1)、6-甲氧基-2-[2-(3-甲氧基-4-羟基苯)乙基]色酮(2)、6,7-二甲氧基-2-(2-苯乙基)色酮(3)、6-羟基-2-(2-苯乙基)色酮(4)、6-羟基-2-[2-(4-甲氧基苯)乙基]色酮(5)、8-氯-6-羟基-2-[2-(3-羟基-4-甲氧基苯)乙基]色酮(6)、8-氯-6-羟基-2-[2-(4-甲氧基苯)乙基]色酮(7)、oxidoagarochromone B(8)、4'-demethoxyaqusisnenone D(9)。其中,化合物6、7和9均为首次从柯拉斯那沉香中分离得到。活性测试结果显示,化合物1和2对乙酰胆碱脂酶具有一定的抑制活性,化合物2对人慢性髓原白血病细胞K562具有较弱的抑制作用。     

Prenylated flavonoids from Deguelia hatschbachii and their systematic significance in Deguelia

Chemical investigation of dichloromethane and petrol extracts from the roots of D. hatshbachii A. M. G. Azevedo furnished thirteen compounds from which five are described for the first time and their structures were determined to be 3-(4'-hydroxyphenyl)-5-methoxy-6-( 3,3-dimethylallyl)-2"2"-dimethylchromene-(5",6":8,7)-3-(propyl-2-one)-4H-1-benzo-2,3-dihydropyran-2,4-dione; 6,4'-dihydroxy-3-(3,3-dimethylallyl)-2",2"-dimethylchromene (5",6":5,4)-2-methoxy deoxybenzoin; 6.4'-dihydroxy-3-(3,3-dimethylallyl)-2",2"-dimethylchromene (5",6":5,4)-2-methoxy-8-(propyl-2-one) deoxybenzon; 6-(3,3-dimethylallyl)-2",2"-dimethylchromene (5",6":4.5)-4'-hydroxy-3-methoxy stilbene and 3,5-dimethoxy-4'-hydroxy-4-(3,3-dimethylallyl) stilbene by spectral analysis (UV, IR, MS and ID- and 2D- NMR experiments). The root extracts and some isolated compounds were bioactive, as revealed by bioautography and brine shrimp lethality assays.     

Molecular Cloning and Construction of agp Gene Deletion-mutant in Cyanobacterium Synechocystis sp. PCC 6803

Nine compounds were isolated from Elsholtzia blanda (Benth.) Benth. Their　structures were identified with spectral and chemical methods as follows: 5,6-dihydro-6-styry-2-pyrone (1), friedelin (2), 4-hydroxy-3-methoxystyrene (3), 5,2′-dimethoxy-6,7-methylene dioxyflavanone (4), 5-hydroxy-7-methoxy-6-O-［α- L -rhamnopyranosyl(1→2)-β- D -fucopyranosyl］ flavone glycoside (5), 5,5′-dihydroxy-7-acetoxyl-6,8,3″,3″-tetramethylpyran　(3′,4′)　flavone (6), 5,5′-dihydroxy-7-(α-methyl) butyroxyl-6,8,3″,3″-tetramethylpyran (3′,4′) flavone (7), 5,5′-dihydroxy-6,7-methylenedioxy-8,3″,3″-trimethylpyran　(3′,4′)　flavone (8), glucosyringic acid (9). Among them, 6, 7 and 8 are new compounds, named as sifanghaoine Ⅰ,Ⅱ and Ⅲ, respectively.     

盘龙参中的两个新二氢菲类

采用硅胶和凝胶柱色谱,以及制备性薄层色谱等多种分离手段,从盘龙参全草中分离得到了2个新的9,10-二氢菲类化合物,运用NMR和MS等波谱技术分别鉴定为4-羟基-2-甲氧基-8-呋喃[4′,5′:7,8]-9,10-二氢菲(1),4-羟基-2-甲氧基-8-{2',2'-二甲基吡喃[5',6':7,8]}-9,10-二氢菲(2).     

Structural confirmation of dihydrocinnamic acids from Adiscanthus fusciflorus by 13C NMR

In the wood of Adiscanthus fusciflorus six known alkaloids 4-methoxy-2-quinolone, 1-methyl-4-methoxy-2-quinolone, dictamine, skimmianine, γ-fagarine and N-methylflindersine and two new dihydrocinnamic acids 3-[2′,6′-dimethoxy-6″,6″-dimethylpyrano(2″,3″:4′, 3′)phenyl]-propionic acid and its methyl ester were identified. The structures of the dihydrocinnamic acid derivatives were confirmed by ¹³C NMR.     

Synthesis and antibacterial activity of egonol derivatives

Synthesis of egonol derivatives, 5-(3'-chloropropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 1, 5-(3'-bromopropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 2, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propanal 3, 5-(3'-iodopropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 4, 5-[3-(3'-bromopropyloxy) propyl]-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 5, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propylmethanoate 6, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propyloleate 7, 5-[3'-hydroxypropyl]-6-bromo-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 8, 4-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]butanenitrile 9, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propylbenzoate 10, 5-[3'-hydroxypropyl]-7-methoxy-3-nitro-2-(3',4'-methylenedioxyphenyl)benzofuran 11 and their antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Candida albicans and Escherichia coli are reported. The starting material egonol 5-[3'-(hydroxy)propyl]-7-methoxy-2-(3', 4'methylenedioxyphenyl)benzofuran was isolated from seeds of Styrax officinalis L. The structural elucidication of these compounds (1-11) was established using 1D ((1)H, (13)C), 2D NMR (HMBC, HMQC, COSY) and LCMS spectroscopic data. While egonol and some synthesised new compounds show similar antibacterial activity and MIC values against S. aureus, B. subtilis, C. albicans and E. coli, other new derivatives show different activity against S. aureus, B. subtilis, C. albicans and E. coli.     

Flavonoids from the roots of Millettia erythrocalyx

From the roots of Millettia erythrocalyx, 6-methoxy-[2",3":7,8]-furanoflavanone, 2,5-dimethoxy-4-hydroxy-[2",3":7,8]-furanoflavan, and 3,4-methylenedioxy-2',4'-dimethoxychalcone were isolated, along with ten other known flavonoids. Their structures were elucidated on the basis of analyses of their spectroscopic data.     

Inhibition of MMP-2 secretion from brain tumor cells suggests chemopreventive properties of a furanocoumarin glycoside and of chalcones isolated from the twigs of Dorstenia turbinata

A furanocoumarin glycoside new named turbinatocoumarin (1) was isolated from the twigs of Dorstenia turbinata. The structure of turbinatocoumarin (1) was assigned as 5-methoxy-3-[3-(beta-glucopyranosyloxy)-2-hydroxy-3-methylbutyl]psoralen by means of spectroscopic analysis. Known compounds have also been isolated from this genus and identified as (2'S, 3'R)-3'-hydroxymarmesin (2), 5-methoxy-3-(3-methyl-2,3-dihydroxybutyl)psoralen (3), psoralen (4), kanzonol C (5) which was isolated for the first time from this genus, 4-hydroxylonchocarpin (6), umbelliferone, 4-hydroxy-3-methoxybenzaldehyde and 4-methoxyphenol. As part of our continuing search for potential naturally-occurring antitumor drug candidates, the inhibition of matrix metalloproteinase (MMP)-2 secretion from brain tumor-derived glioblastoma cells by the isolated compounds 1, 3, 5, and 6 was evaluated by zymography and compared to the documented naturally-occurring MMP secretion inhibitors chlorogenic acid (CHL) and epigallocatechin-3-gallate (EGCg). Among the compounds tested, the inhibiting MMP secretion concentrations ranged from 0.025 to 250 microM with up to 80% inhibition. The inhibitory activities of compounds 5 and 6 were found comparable to the common reference compounds CHL and EGCg. This suggests that alternate sources can be explored and exploited for the availability of chemopreventive molecules.