A new eudesmane sesquiterpene glucoside from Liriope muscari fibrous roots

The screening of several Chinese medicinal herbs for nematocidal properties showed that the ethanol extract of Liriope muscari fibrous roots possessed significant nematocidal activity against the pine wood nematode (Bursaphelenchus xylophilus). From the ethanol extract, a new constituent (1,4-epoxy-cis-eudesm-6-O-β-D-glucopyranoside) and three known glycosides [1β,6α-dihydroxy-cis-eudesm-3-ene-6-O-β-D-glucopyranoside (liriopeoside A), 1β,6β-dihydroxy-cis-eudesm-3-ene-6-O-β-D-glucopyranoside, and 1α,6β-dihydroxy-5,10-bis-epi-eudesm-4(15)-ene-6-O-β D-glucopyranoside] were isolated by bioassay-guided fractionation. The structures were elucidated by 1D and 2D NMR and MS techniques. 1,4-Epoxy-cis-eudesm-6-O-β-D-glucopyranoside possessed moderate nemato-cidal activity against B. xylophilus with a LC(50 )value of 339.76 μg/mL, while liriopeoside A (LC(50) = 82.84 μg/mL) and 1β,6β-dihydroxy-cis-eudesm-3-ene-6-O-β-D-glucopyranoside (LC(50) = 153.39 μg/mL) also exhibited nematocidal activity against B. xylophilus. The crude extract of L. muscari fibrous roots exhibited nematocidal activity against the pine wood nematode with a LC(50) value of 182.56 μg/mL.     

Nematicidal coumarins from Heracleum candicans Wall

The root extract of Heracleum candicans Wall. exhibited antagonistic activities against nematodes Bursaphelenchus xylophilus (Steiner et Buhrer) Nickle and Panagrellus redivivus (Linn.) Goodey. Through bioassay-guided fractionations, three coumarins were obtained from the extract of H. candicans and determined to be 8-geranyloxypsoralen (1), imperatorin (2), and heraclenin (3) based on spectra data. All three compounds possessed nematicidal activities against the two tested nematodes. The median lethal concentrations (LC(50)) of compounds 1-3 at 72 h were 188.3, 161.7, and 114.7 mg L(-1) respectively against B. xylophilus and were 117.5, 179.0, and 148.7 mg L(-1) respectively against P. redivivus. This is the first report about species in the Umbelliferae family that possesses nematicidal activity.     

Screening analyses of pinosylvin stilbenes, resin acids and lignans in Norwegian conifers

The content and distribution of stilbenes and resin acids in Scots pine (Pinus sylvestris) and spruce (Picea abies), sampled in central Norway, have been examined.The contents of pinosylvin stilbenes in pine heartwood/living knots were 0.2-2/2-8 %(w/w). No stilbenes could be detected in spruce (Picea abies). The resin acid contents of pine sapwood/heartwood and knots were 1-4 and 5-10 % (w/w), respectively. Minor amounts of resin acids (<0.2/<0.04 %w/w) were identified in spruce wood/knots. The lignan content in knots of Norwegian spruce was 6.5 % (w/w). Diastereomerically pure hydroxymatairesinol (HMR, 84 % of total lignans) was readily isolated from this source since only minor quantities (2.6 % of total lignans) of the allo-HMR diastereomer was detected. Insignificant amounts of lignans were present in the sapwood. Lignans could not be detected in the sapwood or knots of Norwegian sallow (Salix caprea), birch(Betula pendula) or juniper (Juniperus communis).     

Separation and isolation of major polyphenols from maritime pine (Pinus pinaster) knots by two‐step centrifugal partition chromatography monitored by LC‐MS and NMR spectroscopy

Pine knots are a rich source of lignans, flavonoids, and stilbenes. These bioactive compounds are widely known for their roles to combat human disorders but also to protect plants against pathogens. In order to gain knowledge inside their potential activities, a suitable isolation and purification of these high‐added value compounds is required. To this end, centrifugal partition chromatography, as a rapid and useful methodology of separation, was employed and developed. The coefficient partition values (K_D) of six major compounds in nine biphasic solvent systems were determined to evaluate the most appropriate system. Two‐step centrifugal partition chromatography was required to separate lignans using ARIZONA system K (n‐heptane/ethyl acetate/methanol/water 1:2:1:2, v:v) and to isolate stilbenes and flavonoids using ARIZONA system P (n‐heptane/ethyl acetate/methanol/water 6:5:6:5, v:v). Eight one‐compound enriched‐fractions were obtained as follows: nortrachelogenin (70.1%), secoisolariciresinol (53.7%), isolariciresinol (61.1%), taxifolin (48.4%), pinocembrin (91.3%), pinobanksin (91.1%), pinosylvin (91.4%), and pinosylvin monomethyl ether (91.1%). Additionally, the centrifugal partition chromatography allowed to unravel the composition of pine knot owing to the several fractions generated. Twenty‐two compounds were characterized by liquid chromatography‐mass spectrometry and NMR spectroscopy, some of which are described for the first time in literature.     

Organometallic Derivatization of the Nematocidal Drug Monepantel Leads to Promising Antiparasitic Drug Candidates

The discovery of novel drugs against animal parasites is in high demand due to drug‐resistance problems encountered around the world. Herein, the synthesis and characterization of 27 organic and organometallic derivatives of the recently launched nematocidal drug monepantel (Zolvix^®) are described. The compounds were isolated as racemates and were characterized by ¹H, ¹³C, and ¹⁹F NMR spectroscopy, mass spectrometry, and IR spectroscopy, and their purity was verified by microanalysis. The molecular structures of nine compounds were confirmed by X‐ray crystallography. The anthelmintic activity of the newly designed analogues was evaluated in vitro against the economically important parasites Haemonchus contortus and Trichostrongylus colubriformis. Moderate nematocidal activity was observed for nine of the 27 compounds. Three compounds were confirmed as potentiators of a known monepantel target, the ACR‐23 ion channel. Production of reactive oxygen species may confer secondary activity to the organometallic analogues. Two compounds, namely, an organic precursor ( 3 a ) and a cymantrene analogue ( 9 a ), showed activities against microfilariae of Dirofilaria immitis in the low microgram per milliliter range.     

Synthesis and fungicidal activity of aryl(arylamino)methylphosphonic acids

A series of aryl(arylamino)methylphosphonic acids were synthesized based on the previous work for the modification of alkylphosphonates. As key intermediates, α-aminophosphonates were synthesized with high yield by a three-component Kabachnik–Fields reaction under solvent-free conditions. The compounds were identified and characterized by infrared, ¹H NMR, ¹³C NMR, mass spectrum, and elemental analyses. Their fungicidal activities against typical fungi occurring in the Chinese agro-ecosystems were evaluated. The results of preliminary bioassays showed that some of the title compounds exhibited moderate fungicidal activities against tomato late blight and cucumber fusarium wilt. For example, compound 3b showed 78% inhibitory activity against tomato late blight, and compound 3h possessed 86% inhibitory activity against cucumber fusarium wilt.     

Studies on nepalese crude drugs. XXVIII. Chemical constituents of Bhote Khair, the underground parts of Eskemukerjea megacarpum HARA

From the underground parts of Eskemukerjea megacarpum HARA, two new stilbenes (14, 15) were isolated, together with a known coumarin, 5,7-dihydroxycoumarin (1), a tyramine derivative, trans-feruloyltyramine (2), two pyrogallol derivatives, gallic acid (3) and beta-glucogallin (4), four flavonoids, trifolin (5), hyperin (6), myricetin 3-O-beta-D-galactopyranoside (7), and myricitrin (8), five stilbenes, resveratorol (9), astringenin (10), piceid (11) astringin (12), and resveratorol 3-O-beta-D-(6-O-galloyl)glucopyranoside (13), a flavan-3-ol, (-)-epigallocatechin 3-O-gallate (16), two proanthocyanidins, catechin-(4alpha-->8)-epigallocatechin 3-O-gallate (17) and epicatechin 3-O-gallate-(4beta-->8)-epigallocatechin 3-O-gallate (18), and an anthocyanin, idaein (19). Compounds 14 and 15 were identified as (E)-3,5,3',4'-tetrahydroxystilbene 3-O-beta-D-(6-O-galloyl)glucopyranoside and (E)-3,5,4'-trihydroxystilbene 3-O-beta-D-(6-O-galloyl)glucopyranoside, respectively, based on spectral and chemical data.     

Antifungal Activity of Diketopiperazines and Stilbenes Against Plant Pathogenic Fungi In Vitro

The present study aimed to investigate antifungal activity of a stilbene and diketopiperazine compounds against plant pathogenic fungi, including Phytophthora capsici, P. colocasiae, Botrytis cinerea and Colletotrichum gloeosporioides. Minimal inhibition concentrations (MIC) and minimal fungicidal concentrations (MFC) of stilbenes and diketopiperazines for each fungus were determined using microplate method. Best activity was recorded by stilbenes against P. capsici and P. colocasiae. All four test compounds were effective in inhibiting different stages of the life cycle of test fungi. Stilbenes were more effective than diketopiperazines in inhibiting mycelial growth and inhibiting different stages of the life cycle of P. capsici and P. colocasiae. Rupture of released zoospores induced by stilbenes was reduced by addition of 100 mM glucose. The effects of stilbenes on mycelial growth and zoospore release, but not zoospore rupture, were reduced largely when pH value was above 7. In addition, stilbenes were investigated for its antifungal stability against Phytophthora sp. The results showed that stilbenes maintained strong fungistatic activity over a wide pH range (pH 4–9) and temperature range (70–120 °C). The compound stilbenes exhibited strong and stable broad-spectrum antifungal activity, and had a significant fungicidal effect on fungal cells. Results from prebiocontrol evaluations performed to date are probably useful in the search for alternative approaches to controlling serious plant pathogens.     

Syzygium samarangense leaf extract exhibits distinct antidiabetic activities: Evidences from in silico and in vivo studies

The wax apple, Syzygium samarangense, is widely used in traditional medicine. We have previously described a plethora of biological activities from its leaf extract. These include antioxidant, anti-inflammatory, antiulcer, antitrypanosomal and hepatoprotective effects. Here, we explored the antidiabetic activities from the bioactive leaf extract in silico on two crucial receptors involved in the management of diabetes disease namely peroxisome proliferator activated receptor gamma (PPAR?) and glucagon like peptide-1 (GLP-1) and in vivo against streptozotocin-induced diabetic rats. Altogether, 457 secondary metabolites belonging to 10 classes (phenolic acids (86 compounds), flavonoids (139 compounds), anthocyanins (61 compounds), alkylphenols (17 compounds), chalcone (15 compounds), stilbenes (9 compounds), lignans (29 compounds), tannins (29 compounds), tyrosols (13 compounds), and terpenes and others (59 compounds), were docked into the active site of PPAR? and GLP-1 receptors. From the PDB codes used for each receptor, the co-crystallized ligand was extracted and docked together with a known reference ligand. This was done simultaneously with docking the extract’s compounds to serve as references for comparative purposes. Out of the docked candidates, the top 30 compounds affording the best docking scores were compiled for further inspection and they appeared to exhibit better scores than the respective co-crystallized and reference ligands, highlighting the antidiabetic potential of the tested extract. Nine compounds exhibited highly negative scores on both receptors, demonstrating their high probability of being potent antidiabetic agents through forming stable ligand-receptor complexes. These activities were also confirmed in STZ diabetic rats where the extract reduced the elevated levels of serum glucose and lipid peroxides and increased the declined serum insulin hormone level. Taking all together, S. samarangense can be a potential candidate for further investigations for the treatment of numerous health disorders including diabetes.     

Two new asterosaponins from the Far Eastern starfish Lethasterias fusca

Two new asterosaponins, lethasteriosides A (1) and B (2), were isolated along with previously known thornasteroside A (3), anasteroside A (4), and luidiaquinoside (5) from the ethanolic extract of the Far Eastern starfish Lethasterias fusca. The structures of the new compounds were elucidated by extensive NMR and ESIMS techniques, and chemical transformations. Compounds 1 and 3-5 did not show any apparent cytotoxicity against cancer cell lines T-47D, RPMI-7951, and HCT-116, but glycoside 1, at concentration of 20 microM, demonstrated considerable inhibition of the T-47D (97%), RPMI-795I (90%) and HCT-116 (90%) cell colony formations in a soft agar clonogenic assay.     

New insecticidal amides from petroleum ether extract of dried Piper nigrum L. whole fruits

The petroleum ether extract of dried ground whole fruits of Piper nigrum L. afforded 20 compounds (1-20) including two new insecticidal amides named as pipnoohine (1), and pipyahyine (2), seven reported for the first time from this plant (12, 13, 15-17, 19, 20), and eleven known compounds (3-11, 14, 18). The structure of 1 has been elucidated as (2E,4E,12Z)-N-(4-methylpentyl)octadeca-2,4,12-trienamide and that of 2 as (2E,4E,11E)-12-(benzo[1,3]dioxol-5-yl)-N-(3-methylbutyl)dodeca-2,4,11-trien-amide through extensive ID-, 2D-NMR spectral studies and chemical reactions. The known compounds have been identified through comparison of their spectral data with those reported in literature. 1 and 2 exhibited toxicity at 35.0 and 30.0 ppm respectively against fourth instar larvae of Aedes aegypti L. by WHO method.     

Herbicidal activity of flavonoids of mango leaves against Parthenium hysterophorus L

This study was undertaken to investigate the herbicidal activity of mango (Mangifera indica L.) leaves against parthenium weed (Parthenium hysterophorus L.). The aqueous leaf extract at 15% concentration (on fresh weight basis) significantly reduced germination, shoot length and the shoot and root biomasses of parthenium seedlings. In a leaf residue incorporation pot trial, 2% residue incorporation treatment significantly suppressed the root and shoot biomasses of parthenium, while a 5% residue treatment completely stopped the growth of the weed. Five flavonoids, namely (-)-epicatechin-3-O-β-glucopyranoside (1), 5-hydroxy-3-(4-hydroxyphenyl)pyrano[3,2-g]chromene-4(8H)-one (2), 6-(p-hydroxybenzyl)taxifolin-7-O-β-D-glucoside (tricuspid) (3), quercetin-3-O-α-glucopyranosyl-(1 → 2)-β-D-glucopyranoside (4) and (-)-epicatechin(2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H chromene-3,5,7-triol (5) were isolated from mango leaves. In a laboratory bioassay, 50 ppm solution of compounds 3 and 4 caused yellowing of the parthenium seedlings. A 250 ppm solution of compound 4 also significantly reduced germination and the root and shoot lengths of parthenium seedlings. This study concludes that compound 4 exhibits herbicidal activity against parthenium weed.     

Metabolism of three trichothecene mycotoxins, T-2 toxin, diacetoxyscirpenol and deoxynivalenol, by bovine rumen microorganisms

The three trichothecene mycotoxins T-2 toxin, diacetoxyscirpenol (DAS) and deoxynivalenol (DON) were incubated in vitro for 12, 24 and 48 h with rumen microorganisms obtained from a fistulated dairy cow. Gas chromatographic and gas chromatographic-mass spectrometric analyses of extracts indicated all three toxins were biotransformed to a variety of deepoxy and deacylated products. DON was partially converted to a product identified as deepoxy DON. DAS was rapidly converted to four products including 15-monoacetoxyscirpenol (MAS), scirpentriol and two new compounds identified as 15-acetoxy-3 alpha,4 beta-dihydroxytrichothec-9,12-diene (deepoxy MAS) and 3 alpha,4 beta,15-trihydroxytrichothec-9,12-diene (deepoxy scirpentriol). T-2 toxin was also completely biotransformed to the products HT-2, T-2 triol and two new metabolites identified as 15-acetoxy-3 alpha,4 beta-dihydroxy-8 alpha-(3-methylbutyryloxy) trichothec-9,12-diene (deepoxy HT-2) and 3 alpha,4 beta,15-trihydroxy-8 alpha-(3-methylbutyryloxy)trichothec-9,12-diene (deepoxy T-2 triol).     

闭苞买麻藤中的芪类化合物

对闭苞买麻藤植物进行了系统的化学成分研究，从65%的乙醇提取部分得到了 6介二苯乙烯单体化合物，分别为闭苞素D (1)，闭苞素E(2),丹叶大黄素(3),异丹 叶大黄素(4),4-甲氧基白藜芦醇(5)和银松素(6)，通过光谱方法（包括EI-MS,UV, IR,~1H NMR,~13C NMR和NOE）确定了它们的结构，其中，闭苞素D(1)，闭苞素E(2) 为两个新的二苯乙烯单体化合物。     

Calculation of <Superscript>15</Superscript>N NMR chemical shifts of amines in the framework of the density functional theory

The ¹⁵N NMR magnetic shielding constants (followed by recalculation into chemical shifts) in a representative series of amines were calculated in the framework of the density functional theory. The results were compared with experiment. The accuracy factors of this calculation (functional, basis set, solvent effects, and multistandard) were studied. Taking into account all the above factors leads to a noticeable decrease in the average absolute error in the calculation of the ¹⁵N NMR chemical shifts (from 13 to 4 ppm) in a range of their changing in the studies series of compounds of ～60 ppm (which is 6—7% in relative units).     

丹皮酚噻唑类化合物的合成及其细胞毒性评价

本文以丹皮酚为原料合成了15个新型丹皮酚噻唑衍生物,利用IR、~1H NMR、~(13)C NMR和MS对所得化合物的结构进行表征,采用MTT法考察了目标化合物对MGC-803(胃癌细胞)、LOVO(结肠癌细胞)、T-24(膀胱癌细胞) 3种细胞的体外抗肿瘤活性。结果表明,部分化合物具有良好的细胞毒活性,其中化合物4b、4e、4f、4h、4l对MGC-803的细胞毒性优于阳性对照药顺铂,尤其是化合物4b对MGC-803、LOVO和T-24三种肿瘤细胞的IC_(50)值分别为11. 39±4. 46、2. 06±1. 27和6. 03±0. 86μg/m L,值得进一步研究。     

Antifungal activity of flavonoids isolated from mango (Mangifera indica L.) leaves

Five flavonoids, namely (-)-epicatechin-3-O-β-glucopyranoside (1), 5-hydroxy-3-(4-hydroxylphenyl)pyrano[3,2-g]chromene-4(8H)-one (2), 6-(p-hydroxybenzyl)taxifolin-7-O-β-D-glucoside (tricuspid) (3), quercetin-3-O-α-glucopyranosyl-(1 → 2)-β-D-glucopyranoside (4) and (-)-epicatechin(2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H-chromene-3,5,7-triol (5), were isolated from the leaves of mango (Mangifera indica L.). Antifungal activity of these compounds was evaluated against five fungal species, namely Alternaria alternata (Fr.) Keissler, Aspergillus fumigatus Fresenius, Aspergillus niger van Tieghem, Macrophomina phaseolina (Tassi) Goid. and Penicillium citrii. Six concentrations, namely 100, 300, 500, 700, 900 and 1000 ppm of each of the five flavonoids were employed by means of the poisoned medium technique. All concentrations of the five test flavonoids significantly suppressed fungal growth. However, the specificity of different test compounds was evident against different fungal species. In general, antifungal activity of the flavonoids was gradually increased by increasing their concentrations. The highest concentration (of 1000 ppm) of compounds 1-5 reduced the growth of different target fungal species by 63-97%, 56-96%, 76-99%, 76-98% and 82-96%, respectively.     

New triterpene aldehydes,lucialdehydes A-C,from Ganoderma lucidum and their cytotoxicity against murine and human tumor cells

Three new lanostante-type triterpene aldehydes, named lucialdehydes A-C (1-3), were isolated from the fruiting bodies of Ganoderma lucidum, together with ganodermanonol (4), ganodermadiol (5), ganodermanondiol (6), ganodermanontriol (7), ganoderic acid A (8), ganoderic acid B8 (9), and ganoderic acid C1 (10). The structures of the new triterpenes were determined as (24E)-3 beta-hydroxy-5 alpha-lanosta-7,9(11),24-trien-26-al (1), (24E)-3,7-dioxo-5 alpha-lanosta-8,24-dien-26-al (2), and (24E)-3 beta-hydroxy-7-oxo-5 alpha-lanosta-8,24-dien-26-al (3), respectively, by spectroscopic means. The cytotoxicity of the compounds isolated from the ganoderma mushroom was tested in vitro against Lewis lung carcinoma (LLC), T-47D, Sarcoma 180, and Meth-A tumor cell lines. Lucialdehydes B, C (2, 3), ganodermanonol (4) and ganodermanondiol (6) showed cytotoxic effects on tested tumor cells. Of the compounds, lucialdehyde C (3) exhibited the most potent cytotoxicity against LLC, T-47D, Sarcoma 180, and Meth-A tumor cells with ED(50) values of 10.7, 4.7, 7.1, and 3.8 microg/ml, respectively.     

Determination of stilbene derivatives in Burgundy red wines by ultra-high-pressure liquid chromatography

The polyphenols, for example stilbenes and flavonoids, are an important family of compounds present in grapes and wines. Several studies have shown that stilbenes are antioxidants and cancer-preventing agents. For the first time, eight natural stilbenes (trans-resveratrol, trans-piceid, cis-piceid, trans-astringin, trans-piceatannol, (+)-trans-ε-viniferin, pallidol, and hopeaphenol), isolated and purified from Vitis vinifera, were simultaneously analysed by ultra-high-pressure liquid chromatography coupled with photodiode-array detection. Separation of the stilbenes by UHPLC was optimized with the assistance of “Quality-by-Design” commercial software. Four different reversed-phase columns packed with 1.5–1.7-μm particles were tested and compared for their retention behaviour and separation efficiency. On the basis of the performance characteristics determined, the VisionHT C18 HL column was selected for the stilbenes studied, because resolution of the critical pair was 1.5 with a peak width of 2–4 s. The optimized method resulted in highly repeatable retention times (RSD 0.03–0.07%), peak areas (RSD 3–6%), and linear ranges were between 0.005 and 50 mg L⁻¹ for most of the compounds. All stilbenes, except trans-astringin, trans-piceatannol, and pallidol were identified and quantified in Burgundy red wines at different concentrations after direct injection of the wines.     

Cytotoxicity of labdane-type diterpenoids from Hedychium forrestii

Two new labdane-type diterpenoids, hedyforrestin D (1) and 15-ethoxy-hedyforrestin D (2), and three known compounds, yunnancoronarin A (4), B (3) and C (5) were isolated from the rhizomes of Hedychium forrestii. The structure of the new diterpenoids was established as 6beta,15xi-dihydroxylabda-8(17),11,13-trien-15,16-olide (1), and 6beta-hydroxy-15xi-ethoxylabda-8(17),11,13-trien-15,16-olide (2) on the basis of spectroscopic analyses. In addition, the isolated compounds were evaluated for their cytotoxicity against the lung adenocarcinoma cells A549 and leukemia cells K562 through 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assays. Of these, compounds 3 and 4 exhibited the most activity with IC(50) values of 0.92 and 2.20 microM, respectively, whereas 5 was inactive against A549 cells and 1 was inactive against both cell lines up to a concentration of 300.81 microM. This shows that both the hydroxy substitution and orientation of unsaturated lactone group in the five-membered ring of C-13 to C-16 seem to play an important role in the anti-tumor activities of human lung adenocarcinoma and leukemia.