Quinazolin-4-one derivatives from Streptomyces isolates

From the ethyl acetate extract of the strain Streptomyces sp. isolate GW23/1540, besides 16 known products, several 1H-quinazolin-4-one derivatives were isolated. (SR)-2-(1-Hydroxyethyl)-2-methyl-2,3-dihydro-1H-quinazolin-4-one (4) and (RR)-2-(1-hydroxyethyl)-2-methyl-2,3-dihydro-1H-quinazolin-4-one (5) are new natural products. 2-Methyl-3H-quinazolin-4-one (2) and 1H-quinazoline-2,4-dione (3) are known from other bacteria and plants, respectively. From another Streptomyces sp., GW2/577, 5-methyl-1H-quinazoline-2,4-dione (6) was isolated and the structure proven by comparison with the isomeric 7. The new natural products showed no activity against the microalgae Chlorella vulgaris, Chlorella sorokiniana, and Scenedesmus subspicatus, the fungus Mucor miehei, the yeast Candida albicans, and the bacteria Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Streptomyces viridochromogenes.     

Julichrome Q6 glucuronide, a monomeric subunit of the julimycin B-I complex from a terrestrial Streptomyces sp

The terrestrial Streptomyces sp. isolate GW6225 afforded julichrome Q 6 glucuronide ( 9), the first monomeric member of the julimycin-B complex, and additionally the julichromes Q 1.2 ( 7a), Q 1.5 ( 7b), and Q 3.5 ( 8), which were fully characterized by 2D NMR spectra. Additional new microbial compounds were 4-acetylchrysophanol ( 6a) and N-phenyl-beta-naphthylamine ( 10). The isomeric N-phenyl-alpha-naphthylamine ( 11) was found in the marine Streptomyces sp. B8335 and was also characterized. The high antibiotic activity of Streptomyces sp. GW6225 extracts was probably due to the thiazolyl cyclopeptide nosiheptide.     

Benzyl derivatives with in vitro binding affinity for human opioid and cannabinoid receptors from the fungus Eurotium repens

Bioassay-guided fractionation of the fungus Eurotium repens resulted in the isolation of two new benzyl derivatives, (E)-2-(hept-1-enyl)-3-(hydroxymethyl)-5-(3-methylbut-2-enyl)benzene-1,4-diol (1) and (E)-4-(hept-1-enyl)-7-(3-methylbut-2-enyl)-2,3-dihydrobenzofuran-2,5-diol (2), along with seven known compounds (3-9) including five benzaldehyde compounds, flavoglaucin (3), tetrahydroauroglaucin (4), dihydroauroglaucin (5), auroglaucin (6), and 2-(2',3-epoxy-1',3'- heptadienyl)-6-hydroxy-5-(3-methyl-2-butenyl)benzaldehyde (7), one diketopiperazine alkaloid, echinulin (8), and 5,7-dihydroxy-4-methylphthalide (9). The chemical structures of these compounds were established on the basis of extensive 1D and 2D NMR and HRMS data. Compounds 1-4 and 6 showed good binding affinity for human opioid or cannabinoid receptors. These findings have important implications for psychoactive studies with this class of compounds.     

New antioxidant hydroquinone derivatives from the algicolous marine fungus Acremonium sp

A marine fungal isolate, identified as Acremonium sp., was mass cultivated and found to produce two novel hydroquinone derivatives, 7-isopropenylbicyclo[4.2.0]octa-1,3,5-triene-2,5-diol (1) and 7-isopropenylbicyclo[4.2.0]octa-1,3,5-triene-2,5-diol-5-beta-D-glucopyranoside (2). Compound 1 and its glucoside 2 possess a most unusual ring system. The new natural products (3R,4S)-3,4-dihydroxy-7-methyl-3,4-dihydro-1(2H)naphthalenone (3) and (3S,4S)-3,4-dihydroxy-7-methyl-3,4-dihydro-1(2H)-naphthalenone (4) were obtained as a 1:0.8 mixture. 2-(1-Methylethylidene)pentanedioic acid (5) was isolated for the first time as a natural product and its structure proven by X-ray analysis. In addition to these compounds an inseparable mixture of three new isomeric compounds, pentanedioic acid 2-(1-methylethylidene)-5-methyl ester (6), pentanedioic acid 2-(1-methylethylidene)-1-methyl ester (7), and pentanedioic acid 2-(1-methylethenyl)-5-methyl ester (8), was also obtained. Isolated together with the new compounds were three known hydroquinone derivatives, 9, 10, and 11. The structures of all compounds were determined by interpretation of their spectroscopic data (1D and 2D NMR, MS, UV, and IR). Each isolate was tested for its antioxidant properties, and compounds 1 and 9-11 were found to have significant activity.     

Three new furan derivatives and a new fatty acid from a Taiwanese marine sponge Plakortis simplex

Three new furan derivatives, plakorsins A-C (6-8), together with a new fatty acid, plakortic acid (9), have been isolated from the Taiwanese marine sponge Plakortis simplex in addition to the known metabolites chondrillin (1), 6-epi-chondrillin (2), 2-oxo-2,5-dihydrofuran-5-acetic acid methyl ester (methyl 1,4-epoxy-1-oxo-2-hexenoate) (3), dimethyl beta-ketoadipate (4), and the monomethyl ester of cis,cis-muconic acid (5). The structures of these compounds were established mainly on the basis of spectral data and chemical methods. Biological studies revealed that compound 7 exhibited cytotoxic activity against COLO-250 and KB-16 cells, and compound 1 is active against KB-16 cells.     

Cucurbitosides F-M, acylated phenolic glycosides from the seeds of Cucurbita pepo

Eight new phenolic glycosides, cucurbitosides F-M (1-8), were isolated from the seeds of Cucurbita pepo. Their structures were elucidated as 4-(2-hydroxyethyl)phenyl 5-O-(2-S-2-methylbutyryl)-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (1), 4-(2-hydroxyethyl)phenyl 5-O-(3-methylbutyryl)-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (2), 4-(2-hydroxyethyl)phenyl 5-O-nicotinyl-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (3), 4-(2-hydroxyethyl)phenyl 5-O-(4-aminobenzoyl)-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (4), 4-(2-hydroxyethyl)-2-methoxyphenyl 5-O-(2-S-2-methylbutyryl)-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (5), 4-(hydroxymethyl)phenyl 5-O-(2-S-2-methylbutyryl)-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (6), 4-(hydroxymethyl)phenyl 5-O-nicotinyl-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (7), and 4-(hydroxymethyl)phenyl 5-O-(4-aminobenzoyl)-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (8) on the basis of various spectroscopic analyses and analyses of hydrolysis products.     

Two new xanthone derivatives from the algicolous marine fungus Wardomyces anomalus

A marine fungal isolate, identified as Wardomyces anomalus, was cultivated and found to produce two new xanthone derivatives, 2,3,6,8-tetrahydroxy-1-methylxanthone (1) and 2,3,4,6,8-pentahydroxy-1-methylxanthone (2), in addition to the known xanthone derivative 3,6,8-trihydroxy-1-methylxanthone (3) and the known fungal metabolite 5-(hydroxymethyl)-2-furanocarboxylic acid (4). The structures of all compounds were determined on the basis of extensive spectroscopic measurements (1D and 2D NMR, MS, UV, and IR). Compounds 1 and 4 showed significant antioxidant activities. The total extract and 1, 3, and 4 were shown to be inhibitors of p56(lck)tyrosine kinase.     

Maleimide and maleic anhydride derivatives from the mycelia of Antrodia cinnamomea and their nitric oxide inhibitory activities in macrophages

On cultivation of the fungus Antrodia cinnamomea (BCRC 36799) on a medium, the mycelium was extracted and evaluated for nitric oxide (NO) inhibitory activity. Bioactivity-directed fractionation led to the isolation of two new maleimide derivatives, antrocinnamomins A (1) and B (2), and two new maleic anhydride derivatives, antrocinnamomins C (3) and D (4), along with three known compounds, 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]furan-2,5-dione (5), 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]-1H-pyrrole-2,5-dione (6), and 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]-1H-pyrrol-1-ol-2,5-dione (7). Structural elucidation of compounds 1-4 was carried out by spectroscopic data. Compound 1 displayed significant inhibitory effect on nitric oxide (NO) production.     

1,2-bis(1H-indol-3-yl)ethane-1,2-dione, an indole alkaloid from the marine sponge Smenospongia sp

1,2-Bis(1H-indol-3-yl)ethane-1,2-dione (1), a bisindole alkaloid, was isolated from the marine sponge Smenospongia sp. The known compounds indole-3-carbaldehyde (2), 6-bromoindole-3-carbaldehyde (3), and tryptamine (4) and mixtures of the (Z/E) isomers of 6-bromo-2'-demethylaplysinopsin (5a/5b) and 6-bromo-3'-deimino-2',4'-bis(demethyl)-3'-oxoaplysinopsin (6a/6b) were also isolated.     

猫爪草中吡咯丁酸的含量测定研究

 目的 探寻猫爪草中指标性成分,并建立HPLC测定猫爪草中指标性成分含量的方法,对猫爪草进行质量控制研究。方法 采用不同柱色谱技术进行分离,通过光谱、波谱分析鉴定指标性成分吡咯丁酸的化学结构。采用高效液相色谱法进行吡咯丁酸的含量测定,以Agilent TC-C₁₈ 柱（4.6 mm×250 mm,5 μm）色谱柱为固定相;流动相为0.4%醋酸水-甲醇;检测波长：292 nm;体积流量：1.0 mL·min^-1。结果 猫爪草中指标性成分经分离、鉴定为吡咯丁酸,吡咯丁酸在0.372～1.302 μg线性关系良好,r²=0.999 8。平均回收率为100.89% (RSD=0.83%)。结论 本方法简单、快速、可靠,为猫爪草的质量控制提供了科学依据。     

Pharacine,a natural p-cyclophane and other indole derivatives from Cytophaga sp. strain AM13.1

From the ethyl acetate extract of the bacterial strain Cytophaga sp. AM13.1, among many known compounds, the new natural products 2,5-bis(3-indolylmethyl)pyrazine (2) and a highly symmetrical p-cyclophane named pharacine (5) were identified. In addition, tryptamine isovalerate (1) and p-hydroxyphenylacetamide (4), known as plant metabolites, were isolated and characterized from a microorganism for the first time. The new natural products showed no activity against three microalgae, the fungus Mucor miehei, the yeast Candida albicans, and the bacteria Staphylococcus aureus, Bacillussubtilis, Escherichia coli, and Streptomyces viridochromogenes.     

A New Cyano-compound from Rhodiola kirilowii

Objective To study the chemical constituents of Rhodiola kirilowii.Methods The compounds were separated and purified by various chromatographic techniques and their structures were elucidated on the basis of physicochemical properties and spectroscopic methods.Results Five compounds were purified and their structures were identified as 4-(β-D-glucopyranosyloxy)-3-hydroxy-2-(hydroxymethyl)-butanenitrile(1),epicatechin(2), arbutin(3),rutin(4),andβ-D-glucose(5).Conclusion Compound 1 is a new cyano-compound and other compounds are isolated from the plant for the first time.     

蜘蛛香炮制品的化学成分和抗炎活性研究

目的 研究蜘蛛香炮制品的化学成分及其抗炎活性。方法 采用正相硅胶柱色谱、羟丙基葡聚糖凝胶(Sephadex LH-20)、ODS和高效液相色谱(HPLC)等多种分离材料和方法进行分离纯化,通过理化性质及波谱数据鉴定化合物结构,采用脂多糖(LPS)诱导的RAW264.7细胞体外炎症模型,以总一氧化氮合成酶抑制剂(L-NMMA)作为阳性对照,对化合物进行体外抗炎活性评价。结果 从蜘蛛香炮制品的乙酸乙酯相共分离鉴定了25个化合物,分别为(3S,4R,5S,7S,8S,9S)-3,8-环氧-7-羟基-4,8-二甲基全氢环戊基[c]吡喃(1)、(3S,4S,5S,7S,8S,9S)-3,8-环氧-7-羟基-4,8-二甲基全氢环戊基[c]吡喃(2)、去酰基缬草醛(3)、缬草醛(4)、8-羟基-7′-表松脂醇(5)、(+)-表松脂醇(6)、青刺尖木脂醇(7)、 (7R,8S,7′R,8′S)-5-甲氧基青刺尖木脂醇(8)、(-)-松脂醇(9)、绿原酸(10)、橙皮素(11)、3,8-二羟基-2-甲基色原酮(12)、penicisochroman J(13)、2,5-二(4-羟基-3-甲氧基苯基)-1,4-二烷(14)、4,4′-二羟基-3,3′-二甲氧基-反式-1,2-二苯乙烯(15)、对苯二酚(16)、4-羟基-3-甲氧基苯甲醛(17)、乙酰香草酮(18)、4-羟基-3-甲氧基桂皮醛(19)、2,3-二羟基-1-甲氧基苯(20)、5-羟甲基-2-呋喃甲醛(21)、5-乙酰糠醇(22)、5-[(5-(hydroxymethyl)furan-2-yl)methoxymethoxymethyl]furan-2-carbaldehyde(23)、5-({5-[(5-(hydroxy methyl)furan-2-yl)methoxy(methoxymethyl)]-furan-2-yl} methoxy(methoxymethyl)) furan-2-carbaldehyde(24)和6-羟基-2H-吡喃-3-醛(25)。其中,化合物3,15,16和19均能够显著抑制RAW264.7细胞中脂多糖诱导的一氧化氮生成,且呈显著的剂量依赖性,表现出潜在的抗炎活性。结论 炮制后的蜘蛛香化合物结构类型涉及环烯醚萜及其降解产物、苯丙素、黄酮、色原酮、芳香衍生物和糠醛衍生物等。在炮制过程中,主要是环烯醚萜和单糖的结构发生了变化;化合物 5、6、9~25均为首次从蜘蛛香中分离得到,其中,化合物3,15,16和19具有抗炎活性,半数抑制浓度(IC₅₀)值分别为29.04、10.77、6.37和10.98 μmol·L^-1。     

10-membered macrolides from the insect pathogenic fungus Cordyceps militaris BCC 2816

Three new 10-membered macrolides (1-3) have been isolated from the entomopathogenic fungus Cordyceps militaris BCC 2816, together with six known compounds, cepharosporolides C (4), E (5), and F (6), 2-carboxymethyl-4-(3'-hydroxybutyl)furan (7), cordycepin (8), and pyridine-2,6-dicarboxylic acid. The structures were determined by analysis of NMR data, and an X-ray analysis was performed to confirm the structure of 1. The antimalarial activity of 1-4 and 8 against Plasmodium falciparum K1 was evaluated.     

Microbial metabolism studies of cyanthiwigin B and synergetic antibiotic effects

Microbial transformation studies of the marine diterpene cyanthiwigin B (1), isolated from the Jamaican sponge Myrmekioderma styx, were accomplished. Two actinomycete cultures, Streptomyces NRRL 5690 and Streptomyces spheroides, significantly metabolized cyanthiwigin B to new metabolites. Streptomyces NRRL 5690 transformed cyanthiwigin B to three new compounds, cyanthiwigins AE (2), AF (3), and AG (4), and the known cyanthiwigin R (5). S. spheroides transformed cyanthiwigin B to cyanthiwigins S (6), E (7), and AE (2). All microbial-metabolized derivatives (2-7) of cyanthiwigin B exhibited the ability to increase the antimicrobial activity of curcuphenol, the major antimicrobial sesquiterpene isolated from M. styx.     

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??OBJECTIVE To study the chemical constituents of Citrus aurantium L. METHODS Chromatographic techniques were employed for isolation and purification of the constituents and their structures were determined by spectral analysis and chemical evidence. RESULTS Sixteen compounds were obtained and identified as pyrrolezanthine-6-methyl ether (1), methyl 3-hydroxy-4-methoxybenzoate (2), 3-hydroxy-4-methoxybenzoic acid (3), methyl 3,4-dihydroxybenzoate (4), methyl 3-(4-acetoxyphenyl)propanoate (5), 4-hydroxybenzoic acid (6), scopoletin (7), 5-(hydroxymethyl)furan-2-carbaldehyde (8), hesperidin (9), naringin (10), gossypetin-8,3'-dimethylether-3-O-??-D-galactoside (11), 2-homoeriodictyol-7-O-??-D-glucopyranoside (12), 6-demethoxytangeretin (13), naringenin (14), 5,6,7,8,4'-pentamethoxyflavone (tangeretin) (15), and 5-O-desmethylnobiletin (16). CONCLUSION Compounds 1??2??4??8??11-13 are for the first time obtained from Citrus.     

Flavonoids from Dalbergia louvelii and their antiplasmodial activity

Four new flavonoids (1-4), along with 13 known compounds, were isolated from the heartwood of Dalbergia louvelii by following their potential to inhibit in vitro the growth of Plasmodium falciparum. Of the isolated compounds, four known compounds showed antiplasmodial activity with IC(50) values ranging from 5.8 to 8.7 microM, namely, (R)-4' '-methoxydalbergione (5), obtusafuran (6), 7,4'-dihydroxy-3'-methoxyisoflavone (7), and isoliquiritigenin (8). The structures of the new compounds were determined using spectroscopic techniques as 1-(3-hydroxyphenyl)-3-(4-hydroxy-2,5-dimethoxyphenyl)propane (1), spirolouveline (2), (3R)-7,2'-dihydroxy-4',5'-dimethoxyisoflavanone (3), and 3-(2,4-dihydroxy-5-methoxy)phenyl-7-hydroxycoumarin (4), respectively.     

Terphenylquinone inhibitors of the src protein tyrosine kinase from Stilbella sp

Three new secondary metabolites, 2,5-dihydroxy-3-(3,4-dihydroxyphenyl)-6-phenyl-1,4-benzoquinone (3), 2,5-dihydroxy-3-phenyl-6-(3,4,5-trihydroxyphenyl)-1,4-benzoquinone (4), and 2,7,8-trihydroxy-3-phenyl-1,4-dibenzofurandione (5), as well as two known natural products were isolated from the fungus Stilbella sp. strain 1586. The structures of these compounds were established by spectroscopic and chemical methods. The terphenylquinones 3-5 exhibited significant activity against human src protein tyrosine kinase.     

Anthraquinones with quinone reductase-inducing activity and benzophenones from Morinda citrifolia (noni) roots

Two new benzophenones, morintrifolins A ( 1) and B ( 2), together with 14 known anthraquinones and four other known compounds, were isolated from a chloroform-soluble extract of Morinda citrifolia roots. Of the isolated compounds, four known anthraquinones, namely, 1,2-dihydroxyanthraquinone ( 3), 1,3-dihydroxy-2-methylanthraquinone ( 4), 2-hydroxy-3-(hydroxymethyl)anthraquinone ( 5), and 1,3,6-trihydroxy-2-methylanthraquinone ( 6), exhibited quinone reductase (QR)- inducing activity in Hepa lclc7 cells, with concentrations required to double QR activity of 12.0, 8.1, 0.94, and 0.56 microM, respectively.     

Extracellular carbohydrate metabolites from Streptomyces coelicolor A3(2)

A new ribose trisaccharide, alpha-Ribf-(1-->2)-alpha-Ribf-(1-->3)-alpha-Ribf (1), was isolated together with 5-O-(alpha-mannosyl)-myo-inositol (2), 2-O-(alpha-mannosyl)-myo-inositol (3), trehalose (4), and d-ribulose (5) from a submerged cultivation of Streptomyces coelicolor A3(2). The structures of these compounds were elucidated by spectroscopic and chemical methods. Concentrations of these compounds in the medium were in the range from 0.04 (1) to 0.5 (4) mg/mL.