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Seven previously undescribed preurianin-type limonoids, namely paraxylines A-G, and three known analogs were isolated from stem bark of Dysoxylum parasiticum. The structures, including absolute configurations, were established through spectroscopic analyses, quantum chemical calculations using the density functional theory method, as well as the DP4+ algorithm. Paraxylines A-G were identified as the first preurianin-type with full substitution at C, D-rings, leading to the highly oxygenated seco- limonoids skeleton. The secreted alkaline phosphate assay against an engineered human and murine TLR4 of HEK-Blue cells was performed to evaluate the immune regulating effects. Among them, paraxyline B was found to be a remarkable TLR4 agonist whereas two analogs (toonapubesins A and B) were found to antagonise lipopolysaccharide stimulation of the TLR4 pathway. Paraxylines A and C-E acted either as agonists or antagonists depending on the origin of the TLR4 receptor (human or mouse). The effect of these selected compounds on the expression of pro-inflammatory cytokines TNF- α , IL-1 α , IL-1 β , and IL-6 of the NF- κ B signaling pathway were examined in macrophage cell lines, revealing dose-dependent effects. Additionally, paraxylines A, C, D, and G also presented modest cytotoxic activity against MCF-7 and HeLa cell lines with IC 50 values ranging from 23.1 to 43.5 μM. Seven undescribed preurianin-type limonoids, paraxylines A-G, along with three known tirucallanes, were isolated from the stem bark of Dysoxylum parasiticum (Osbeck) Kosterm (Meliaceae). Biological evaluation discovered that paraxyline B (2) was a new TLR4 agonist against human and murine cells. [Display omitted] • Ten triterpenoids were isolated from the stem bark of Dysoxylum parasiticum. • Seven undescribed highly oxygenated preurianin-type limonoids were found. • The absolute configurations were elucidated by ECD and DP4+ algorithm. • Paraxyline B was found to be a new agonist TLR4 against human and murine cells. • Paraxylines A, C, D, and G showed modest cytotoxicity against MCF-7 and HeLa cells. [ABSTRACT FROM AUTHOR]

Terminthia paniculata (Sanyeqi) is widely used for treating inflammation and rheumatic arthritis in the folk areas of Yunnan province, China. Its total extract was first revealed with xanthine oxidase (XO) inhibitory activity in vitro and anti-hyperuricemic effect in vivo. Bioassay-guided separation on Fr. A5 yielded six chalcone-flavonone heterodimers, termipaniculatones A-F. Their structures were elucidated based on extensive spectroscopic analyses involving HRESIMS, 1D and 2D NMR, UV, IR and [ α ] D , and the absolute configuration of termipaniculatone F was verified by ECD calculation. Termipaniculatones A and E showed obvious XO inhibitory activity with IC 50 values of 55.6 and 89.5 μ M, respectively, which took effects via a mix-type mode. A molecular modeling study revealed that termipaniculatone A was well located into the active site of XO by interacting with Glu802, Arg880, Thr1010 and Val1011 residues. Termipaniculatone A showed anti-hyperuricemic effects by decreasing serum uric acid levels and inhibiting XO activity in both serum and liver on potassium oxonate (PO)-induced hyperuricemia mice, and anti-inflammatory activity through alleviating paw swelling on monosodium urate (MSU)-induced mice, at the concentration of 20 mg/kg. This is the first time to reveal the anti-hyperuricemic and anti-acute gouty arthritis potency of T. paniculata and the characteristic biflavonoids as active constituents, which provides valuable information for searching new XO inhibitors from natural sources. Image 1 • Six undescribed chalcone-flavonone heterodimers were isolated from T. paniculata. • Termipaniculatones A and E showed obvious XO inhibition (IC 50 = 55.6 and 89.5 μ M). • Termipaniculatone A protected hyperuricemia and acute gouty arthritis in vivo. [ABSTRACT FROM AUTHOR]

Tree peonies (Paeonia Sect. Moutan) are well-known for their medicinal and ornamental uses but most wild species in the Moutan section are endangered. The comprehensive metabolomics evaluation of tree peonies is essential to distinguish different species and to identify undescribed compounds, thereby elucidating the diversity of their metabolites and discovering potential active ingredients. In this study, the metabolome variations of root barks of nine species and their varieties collected from one botanical garden after years of localization were systematically investigated. A digital database of specialized metabolites was established to improve feature identification or annotation and various bio- and cheminformatics tools were employed to analyse and visualize the profiled metabolomic data. As a result, 384 compounds were identified or annotated, including various monoterpene glycosides, flavonoids, phenols, terpenoids and steroids, tannins, stilbenes and others. All samples were clearly divided into two subsections: Vaginatae and Delavayanae. The distribution and abundance of metabolites were also analysed and discussed in order to find potential biomarkers in different wild tree peonies. The metabolomic profiles of different species in Paeonia Section Moutan were explored by UPLC-QTOF-MS. Various bioinformatics tools and a specialized compound library were employed to enhance the data interpretation. Image 1 • A digital database of secondary metabolites of Paeonia Sect. Moutan was constructed. • Comprehensive metabolic profiling of the root bark of 9 wild species of tree peonies. • Potential biomarkers in different wild tree peonies are discussed and analysed. [ABSTRACT FROM AUTHOR]

Wattle (Acacia mearnsii De Wild., Leguminosae) bark extract is used commercially to tan leather and manufacture adhesives. The extract is treated with sodium hydrogen sulfite (sulfited) to improve its tanning properties. These include reduced viscosity, improved solubility, and better raw skin penetration. High resolution ESIMS allows unambiguous assignment of sulphur-containing monomeric and oligomeric products from sulfitation. It reveals that during sulfitation the constituent flavan-3-ol building blocks are sulfited at both C-2 and C-4 by a sulfite ion. A sulfonic acid moiety is introduced at C-2 to open the pyran ring, and C-4 to cleave the interflavanyl bond and reduce the degree of polymerization, respectively, explaining the improved tanning properties. MS2 fragmentation spectra and comparison with unsulfited extract support the interpretation of peaks and composition of sufited wattle bark extract. It also supports our published work that mimosa bark extract consists of a catechin or gallocatechin starter unit and fisetinidol or robinetinidol extender units. Sulfitation with sodium bisulfite (NaHSO 3) of Acacia mearnsii bark extract were investigated with high resolution electrospray mass spectrometry. Sulphonic acid moieties are introduced on both the C-2 and C-4 positions leading to changes in physical properties of the raw extract. Image 1 • Sulfited Acacia mearnsii De Wild. bark extract was investigated via HR-ESIMS. • Sulfitation of the flavan-3-ol building blocks occurs at both C-2 and C-4. • C-4 sulfitation breaks interflavanyl bonds and C-2 sulfitation opens the pyran ring. • Starter units are catechin and gallocatechin. • Extender units are fisetinidol and robinetinidol. [ABSTRACT FROM AUTHOR]

The phenolic phytochemicals of winter-dormant Salix pyrolifolia were determined from the vegetative buds, and the bark and wood of different-aged twigs by HPLC-DAD and UHPLC-QTOF-MS analyses. All the plant parts were composed of salicylate glucosides and the other Salix -specific, simple phenolic glucosides as well as of phenolic acids, flavonoids and the high molecular-weight condensed tannins. The flavonoid composition was most diverse in buds and they also contained a large amount of chlorogenic acid (5-caffeoylquinic acid IUPAC), while salicylate glucosides and simple phenolic glucosides predominated in bark. The wooden interior part of the twigs contained fewer components and the lowest concentrations of compounds. Salicortin was the main compound in winter-dormant S. pyrolifolia (over 10% of bark biomass), but the concentrations of picein, salireposide, isosalipurposide, catechin and condensed tannins were also high. The flavonoid composition was highly naringenin- and quercetin-biassed. The composition of phytochemicals was organ-specific and remained relatively similar between different-aged trees. However, there were compound-specific fluctuations in the concentrations of phytochemicals with the age of the trees and within plant parts. Generally, the one-year-old plants differed from the older trees in their high concentration of condensed tannins in all the plant parts studied and in the highest concentration of isosalipurposide in bark, while the total amounts of salicylate glucosides in plant parts, and of naringenin glucosides in buds, tended to be highest in 20 year-old-trees. [ABSTRACT FROM AUTHOR]

Ten undescribed triterpene saponins, named erythrosaponins A–J, along with one known analogue were isolated from the roots and stem bark of Gardenia erythroclada . Their structures were determined on the basis of extensive 1D and 2D NMR analyses. Absolute structure of erythrosaponin A was unequivocally affirmed by single-crystal X-ray crystallography. All isolated compounds were evaluated for their cytotoxicity against cancer cell lines (KB and HeLa S-3) and their anti-inflammatory activity based on the inhibition of NO production in RAW264.7 cells. Erythrosaponin D showed moderate cytotoxicity against KB and HeLa S-3 cells with IC 50 values of 25.8 and 29.5 μM, respectively. Erythrosaponins D, F, G, I and J showed moderate anti-inflammatory with IC 50 values in the range of 63.0–81.4 μM. [ABSTRACT FROM AUTHOR]

A series of prenylated flavonoids was obtained from antigenotoxic extracts and fractions of stem bark of Erythrina latissima E. Mey (Leguminosae). In addition to five constituents never reported before, i.e. (2 S )-5,7-dihydroxy-2-(4-hydroxy-2-(prop-1-en-2-yl)-2,3-dihydrobenzofuran-6-yl)chroman-4-one (erylatissin D), (2 S )-5,7-dihydroxy-2-(4-methoxy-2-(prop-1-en-2-yl)-2,3-dihydrobenzofuran-6-yl)chroman-4-one (erylatissin E), 5,7-dihydroxy-3-(4-methoxy-2-(prop-1-en-2-yl)-2,3-dihydrobenzofuran-6-yl)-4H-chromen-4-one (erylatissin F), (2 S )-5,7,8′-trihydroxy-2′,2′-dimethyl-[2,6′-bichroman]-4-one (erylatissin G) and (2 S )-5,7-dihydroxy-8′-methoxy-2′,2′-dimethyl-[2,6′-bichroman]-4-one (dihydroabyssinin I), 18 known flavonoids were identified. Evaluation of the antigenotoxic properties (against genotoxicity induced by aflatoxin B1, metabolically activated) in the Vitotox assay revealed that most flavonoids were active. Sigmoidin A and B showed the highest activity, with an IC 50 value of 18.7 μg/mL, equivalent to that of curcumin (IC 50 18.4 μg/mL), used as a reference antigenotoxic compound. [ABSTRACT FROM AUTHOR]

Extraction and characterization of natural products from the bark of the trunk of Helietta apiculata Benth (Rutaceae) afforded nine alkaloids, eight furoquinoline and one quinolone, limonine, three cinnamic acid derivatives, three neolignans, tetracosanoic acid, six coumarins, of which apiculin A and apiculin B (neolignans), and tanizin (coumarin) are previously undescribed compounds. The structures of all compounds were determined by spectroscopic methods, and the crystal structures of two of the newly undescribed compounds, apiculin A and apiculin B, were determined by X-ray analysis. Extracts and pure compounds isolated from Helietta apiculata showed promising antimicrobial activities. [ABSTRACT FROM AUTHOR]

A phytochemical study on the stem bark of Commiphora opobalsamum looking for cytotoxic compounds afforded eleven flavonoids, including six previously undescribed prenylated congeners, comophorin A – E, and comophoroside A. The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Isolated compounds were biologically evaluated using in vitro cytotoxicity MTT-based assay against two cancer cell lines; namely human hepato-cellular carcinoma (HepG-2) and human breast adenocarcinoma (MCF-7). Comophoroside A revealed to retain the strongest cytotoxic activity against MCF-7 and HepG-2 cell lines with IC 50 values of 8 and 12 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Six previously undescribed triterpenoid saponins and two previously undescribed nor lupane triterpenes were isolated with five known saponins, three known lupane derivatives, 17,20-didehydro-20-deoxyjujubogenin, rutin, (±) 3α- O - β - d -glucopyranosyl-lyoniresinol, (±) 4- O - β - d -glucopyranosyl-maesopsin, three phenol glycosides, and uridine from the stems and bark of Jaffrea xerocarpa (Baill.) H. C. Hopkins & Pillon (= Basionym Alphitonia xerocarpus Baill.) (Rhamnaceae), an endemic tree of New Caledonia. The chemical structures of the purified compounds were identified by nuclear magnetic resonance and mass spectrometry. The isolated compounds were tested for their antioxidant, antityrosinase, antibacterial and cytotoxic activities. The aqueous methanol extract showed antioxidant activity (DPPH assay) due to the presence of rutin and other phenolic compounds. Three lupane triterpenes showed good cytotoxic activities against KB cells line (IC 50 from 7.7 to 8.5 μM). The previously undescribed 2 α -formyl-A(1)norlup-20(29)-en-28-oic acid showed antibacterial activity against Staphylococcus aureus and Enterococcus faecalis with both MIC values of 4 μg/mL. [ABSTRACT FROM AUTHOR]

A dimeric acylphenol and a potent α-glucosidase inhibitor, giganteone D (IC 50 5.05 μM), was isolated and characterized from the bark of Myristica cinnamomea King. The bark also yielded an acylphenol with an unprecedented skeleton for which the name cinnamomeone A (IC 50 358.80 μM) was proposed. Their structures were established by means of NMR and MS spectrometric analyses. The Lineweaver–Burk plot of giganteone D indicated that it was a mixed-type inhibitor. This is the first report on the α-glucosidase inhibiting potential of acylphenols. [ABSTRACT FROM AUTHOR]

Condensed tannins extracted from European softwood bark are recognized as alternatives to synthetic phenolics. The extraction is generally performed in hot water, leading to simultaneous extraction of other bark constituents such as carbohydrates, phenolic monomers and salts. Characterization of the extract’s composition and identification of the extracted tannins’ molecular structure are needed to better identify potential applications. Bark from Silver fir ( Abies alba [Mill.]), European larch ( Larix decidua [Mill.]), Norway spruce ( Picea abies [Karst.]), Douglas fir ( Pseudotsuga menziesii [Mirb.]) and Scots pine ( Pinus sylvestris [L.]) were extracted in water at 60 °C. The amounts of phenolic monomers, condensed tannins, carbohydrates, and inorganic compounds in the extract were determined. The molecular structures of condensed tannins and carbohydrates were also investigated (HPLC-UV combined with thiolysis, MALDI-TOF mass spectrometry, anion exchange chromatography). Distinct extract compositions and tannin structures were found in each of the analysed species. Procyanidins were the most ubiquitous tannins. The presence of phenolic glucosides in the tannin oligomers was suggested. Polysaccharides such as arabinans, arabinogalactans and glucans represented an important fraction of all extracts. Compared to traditionally used species (Mimosa and Quebracho) higher viscosities as well as faster chemical reactivities are expected in the analysed species. The most promising species for a bark tannin extraction was found to be larch, while the least encouraging results were detected in pine. A better knowledge of the interaction between the various extracted compounds is deemed an important matter for investigation in the context of industrial applications of such extracts. [ABSTRACT FROM AUTHOR]

Hispidacine, an 8,4′-oxyneolignan featuring incorporation of an unusual 2-hydroxyethylamine moiety at C-7, and hispiloscine, a phenanthroindolizidine alkaloid, were isolated from the stem-bark and leaves of the Malaysian Ficus hispida Linn. Their structures were established by spectroscopic analysis. Hispidacine induced a moderate vasorelaxant activity in rat isolated aorta, while hispiloscine showed appreciable antiproliferative activities against MDA-MB-231, MCF-7, A549, HCT-116 and MRC-5 cell lines. [ABSTRACT FROM AUTHOR]

In addition to the already reported nukuhivensiums 1 and 2 , 11 indole alkaloids were isolated from the bark of the plant Rauvolfia nukuhivensis , growing in the Marquesas archipelago. The known sandwicine ( 3 ), isosandwicine ( 4 ), spegatrine ( 8 ), lochneram ( 9 ), flavopereirine ( 13 ) have been found in this plant together with the norsandwicine ( 5 ), isonorsandwicine ( 6 ), N b -methylisosandwicine ( 7 ), 10-methoxypanarine ( 10 ), nortueiaoine ( 11 ), tueiaoine ( 12 ). The structure elucidation was performed on the basis of a deep exploration of the NMR and HRESIMS data as well as comparison with literature data for similar compounds. Norsandwicine, 10-methoxypanarine, tueiaoine, and more importantly nukuhivensiums, were shown to significantly induce a reduction of IKr amplitude (HERG current). Molecular modelling through docking was performed in order to illustrate this result. [ABSTRACT FROM AUTHOR]

Highlights: [•] Five oleanane-type glycosides were isolated from the barks. [•] Structures were determined by 2D NMR and by mass spectrometry. [•] Two saponins possessed an unusual substitution of the Fuc-4 position by an ester group formed by two symmetrical C5 nilic acid. [•] Chemotaxonomic conclusions were discussed. [•] Cytotoxicity and anti-iflammatory activity of the isolated compounds were evaluated. [Copyright &y& Elsevier]

Highlights: [•] Five monoterpene indole alkaloids and 10 known ones were isolated from Mitragyna diversifolia. [•] Mitradiversifoline is a rearranged monoterpene oxindole alkaloid containing an unusual oxazine ring from natural sources. [•] Two possible biosynthesis pathways to mitradiversifoline were proposed. [•] All isolates were evaluated for their in vitro acetylcholinesterase inhibitory potential. [Copyright &y& Elsevier]

Highlights: [•] The extracts of the bark of Diospyros bipindensis were active against Candida albicans. [•] HPLC profiles of the polar extracts revealed a complex glycoside composition. [•] The antifungal compound was rapidly identify by HPLC combined with bioautography. [•] 15 Compounds present in the traditional decoction were fully characterised. [•] 9 Coumarin and phenolic glycosides are described for the first time. [Copyright &y& Elsevier]

Highlights: [•] From an aqueous MeOH extract of C. latifolia stem bark, six sesquiterpenes were isolated whose structures have been elucidated by 1D and 2D NMR spectroscopy. [•] Juvenile hormone III, an insect hormone regulating larval metamorphosis and reproduction, was also identified. [•] This finding suggests the extract of C. latifolia or its single active compound potentially be a source of candidates/precursors for development of natural insecticides. [Copyright &y& Elsevier]

Highlights: [•] Ten polyphenols including four known compounds were isolated from Rhus verniciflua bark. [•] Structures were determined based on spectroscopic methods and chemical reaction. [•] Compounds 4–6, 9 and 10 showed antiproliferative activity against the human tumor cells. [•] Compounds 5 and 10 significantly inhibited NO production in LPS-stimulated murine microglia BV-2 cells. [Copyright &y& Elsevier]

Abstract: Nine bisindole alkaloids, comprising four belonging to the macroline–sarpagine group, and five belonging to the macroline–pleiocarpamine group, were isolated from the stem-bark extracts of Alstonia angustifolia (Apocynacea). Their structures were established using NMR and MS analyses. [Copyright &y& Elsevier]

Abstract: Reactive oxygen species (ROS) and granule proteases produced by human neutrophils contribute to the pathogenesis of inflammatory diseases. The MeOH extract of the stem bark of Magnolia officinalis showed potent inhibitory effects on superoxide anion generation and elastase release by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Five biphenyl-type neolignan derivatives, 5-allyl-5′-(1″-hydroxyallyloxy)biphenyl-2,2′-diol, 5,5′-diallyl-2′-(allyloxy)biphenyl-2-ol, 5,5′-diallyl-2′-(3-methylbut-2-enyloxy)biphenyl-2-ol, (E)-5-allyl-3′-(prop-1-enyl)biphenyl-2,4′-diol, and 4-allyl-2-(2′-methylbenzofuran-5′-yl)phenol, have been isolated from the stem bark of M. officinalis, together with 12 known compounds. Several exhibited inhibition (IC50 values⩽10.7μM) of superoxide anion generation by human neutrophils in response to fMLP/CB. Others inhibited fMLP/CB-induced elastase release with IC50 values⩽8.76μM. [Copyright &y& Elsevier]

Abstract: Wattle (Acacia mearnsii) bark extract is an important renewable industrial source of natural polymers for leather tanning and adhesive manufacturing. The wattle bark proanthocyanidin oligomers have 5-deoxy extender units that render the interflavanyl bonds resistant to acid catalysed hydrolysis and their composition cannot be determined via conventional thiolysis. We combined established phyto- and synthetic chemistry perspectives with an electrospray mass spectrometry investigation to establish that the flavan-3-ol based oligomers consist of a starter unit which is either catechin or gallocatechin, angularly bonded to fisetinidol or predominantly robinetinidol extender units. [Copyright &y& Elsevier]

Abstract: Seven compounds, (7′S,8′S)-trans-streblusol A, (7′R,8′S)-erythro-streblusol B, (7′S,8′S)-threo-streblusol B, 8′R-streblusol C, streblusquinone, (8R,8′R)-streblusol D, and streblusol E, along with 15 known compounds (8–22) were isolated from the n-butanol-soluble part of the MeOH extract of stem bark of Streblus asper. Their structures were elucidated through application of extensive spectroscopic methods, including ESI-MS and 2D NMR spectroscopy (HMQC and HMBC). The stereochemistry at the chiral centers was determined using CD spectra, as well as analyses of coupling constants and optical rotation data. The isolated lignans and allylbenzene derivatives were evaluated for their anti-HBV activities in vitro using the HBV transfected Hep G2.2.15 cell line. The most active compounds, magnolol and 9-β-xylopyranosyl-isolariciresinol, exhibited significant anti-HBV activities with IC50 values of 2.03 and 6.58μM for secretion of HBsAg, with no cytotoxicity, and of 3.76 and 24.86μM for secretion of HBeAg, with no cytotoxicity. [Copyright &y& Elsevier]

Abstract: Volatile terpenes are among the most diverse class of defensive compounds in plants, and they are implicated in both direct and indirect defense against herbivores. In terpenes, both the quantity and the diversity of compounds appear to increase the efficiency of defense as a diverse blend of compounds provides a more efficient protection against a broader range of herbivores and limits the chances that an enemy evolves resistance. Theory predicts that plant defensive compounds should be allocated differentially among tissues according to the value of the tissue, its cost of construction and the herbivore pressure on it. We collected volatile terpenes from bark and leaves of 178 individual tree belonging to 55 angiosperm species in French Guiana and compare the kind, amount, and diversity of compounds in these tissues. We hypothesized that in woody plants, the outermost part of the trunk should hold a more diverse blend of volatile terpenes. Additionally, as herbivore communities associated with the leaves is different to the one associated with the bark, we also hypothesized that terpene blends should be distinct in the bark vs. the leaves of a given species. We found that the mixture of volatile terpenes released by bark is different and more diverse than that released by leaves, both in monoterpenes and sesquiterpenes. This supports our hypothesis and further suggests that the emission of terpenes by the bark should be more important for trunk defense than previously thought. [Copyright &y& Elsevier]

Abstract: Five xanthones, 1,4,5,6-tetrahydroxyxanthone (1) and bracteaxanthones III–VI (2–5) together with twenty-six known compounds (6–31), were isolated from the ethanol extract of the stem bark of Garcinia bracteata. Their structures were elucidated via spectroscopic analyses. Growth inhibitory activities of these compounds against the human leukaemic HL-60 cell line were measured in vitro. Compounds 7, 11, and 29 exhibited moderate activities with GI50 values of 2.8, 3.4, and 3.1μM, respectively, and a preliminary structure–activity relationship is discussed. [Copyright &y& Elsevier]

Abstract: A procyanidin dimer xyloside, catechin-(4α→8)-7-O-β-xylopyranosyl-catechin, was isolated from the inner bark of Betula pendula and its structure was determined using 1D and 2D NMR, CD and high-resolution ESIMS. Interestingly, the 7-O-β-xylopyranose unit was found to be present in the lower terminal unit of the dimer. In addition to this procyanidin dimer xyloside, an entire series of oligomeric and polymeric procyanidin xylosides was detected. Their structures were investigated by hydrophilic interaction HPLC–HRESIMS. Procyanidin glycosides are still rarely found in nature. [Copyright &y& Elsevier]

Abstract: Phytochemical investigation of root bark of Celastrus orbiculatus afforded 10 terpenoids and eight known compounds. Their structures were established on the basis of spectroscopic and chemical methods. Celastrol and its dimers and adducts displayed moderate inhibitory activity against T cell proliferation. The reaction of celastrol under acidic conditions was undertaken, and a mechanism is presented, which may help towards modification of its structure and elucidation of the biogenetic routes to natural celastrol derivatives. [Copyright &y& Elsevier]

Abstract: Four vobasinyl-iboga bisindole and one 2-acyl monomeric indole alkaloids were isolated from the stem bark of Muntafara sessilifolia along with eleven known compounds. Their structures and relative stereochemistry were elucidated on the basis of spectroscopic data including 1D and 2D NMR and mass spectrometry (MS). All isolated compounds were evaluated in vitro for antiplasmodial activity against the chloroquine-resistant strain FcB1 of Plasmodium falciparum, and for cytotoxicity against the human lung cell line MRC-5 and the rat skeletal muscle cell line L-6. 3′-Oxo-tabernaelegantine A exhibited antiplasmodial activity (4.4μM IC50) associated with non-significant cytotoxicity (selectivity index of 48). Tabernaelegantine B and D displayed the highest cytotoxicity with IC50 values of 0.47 and 1.89μM on MRC-5 cells, and 0.42 and 2.7μM on L-6 cells, respectively. [Copyright &y& Elsevier]

Abstract: Investigation of the root bark extract of Entandrophragma angolense led to identification of two gedunin-type limonoids 5-hydroxy-7-deacetoxy-7-oxogedunin (1) and 5,6-dehydro-7-deacetoxy-7-oxogedunin (2), and three methyl angolensate derivatives, 6-deacetoxydomesticulide D (3), 6-deacetoxydomesticulide D 21-methylether (4), and entangosin (5), together with known compounds, methyl angolensate (6), 6-acetoxymethyl angolensate (7) and secomahoganin (8). Their structures were established by extensive NMR experiments in conjunction with mass spectrometry. Entangosin is a rare example of a limonoid derivative having a fully O-substituted furan moiety. [Copyright &y& Elsevier]

Abstract: Nine linear C23 and C21 acetogenins, named cananginones A–I (1–9), were isolated from stem bark of Cananga latifolia. Their structures were established by spectroscopic methods. These compounds showed cytotoxicity against three cancer cell lines (KB, MCF7 and NCI-H187) with IC50 values in the range 16.6–129.7μM. Only 5 showed weak antimalarial activity against Plasmodium falciparum. In addition, 8 and 9 exhibited weak antifungal activity against Candida albicans. [Copyright &y& Elsevier]

Abstract: Friedolanostanes, (22Z,24E)-3β-acetoxy-9α-hydroxy-17,14-friedolanosta-14,22,24-trien-26-oic acid, (22Z,24E)-3β,9α-dihydroxy-17,14-friedolanosta-14,22,24-trien-26-oic acid, (22Z,24E)-9α-hydroxy-3-oxo-17,14-friedolanosta-14,22,24-trien-26-oic acid, a friedocycloartane, (22Z,24E)-3α-hydroxy-17,13-friedocycloarta-12,22,24-trien-26-oic acid, and a benzophenone, benthaphenone, together with known compounds (22Z,24E)-3α,9α-dihydroxy-17,13-friedolanosta-12,22,24-trien-26-oic acid, methyl (24E)-3α,23-dihydroxy-17,14-friedolanosta-8,14,24-trien-26-oate, glutinol, lupeol, and stigmasterol, were isolated from leaves and bark of Garcinia benthami. Their structures were elucidated using spectroscopic techniques, mainly 1-D and 2-D NMR spectroscopy, and chemical correlations. [ABSTRACT FROM AUTHOR]

Abstract: Five spirocaracolitone triterpenoids were isolated from the dichloromethane-soluble fraction of the bark of Ruptiliocarpon caracolito, and their structures were determined mainly by application of 1D and 2D NMR spectroscopy. Two known CD-spirotriterpenoids were also isolated from the same source. This brings the total number of known CD-spirotriterpenoids from this source to 17. The discovery of such a large number of closely-related compounds in a single species represents an excellent example of phytochemical redundancy as a defense mechanism. [Copyright &y& Elsevier]

Abstract: Two amides, heitziamide A and heitziamide B and two phenylethanoids, heitziethanoid A and heitziethanoid B together with thirteen known compounds were isolated from F. heitzii (Letouzey). The structures of all compounds were established by spectroscopic analysis. Nine compounds were evaluated for oxidative burst inhibitory activity in a chemoluminescence assay and for cytotoxicity against PC-3 prostate cancer cells. All compounds exhibited a clear suppressive effect on phagocytosis response upon activation with serum opsonized zymosan at the range of IC50 =2.0–6.5μM, but no cytotoxic effect was observed (IC50 >100μM). [Copyright &y& Elsevier]

Abstract: The latex of Hevea brasiliensis, expelled upon bark tapping, is the cytoplasm of anastomosed latex cells in the inner bark of the rubber tree. Latex regeneration between two tappings is one of the major limiting factors of rubber yield. Hevea species contain high amounts of cyanogenic glucosides from which cyanide is released when the plant is damaged providing an efficient defense mechanism against herbivores. In H. brasiliensis, the cyanogenic glucosides mainly consist of the monoglucoside linamarin (synthesized in the leaves), and its diglucoside transport-form, linustatin. Variations in leaf cyanide potential (CNp) were studied using various parameters. Results showed that the younger the leaf, the higher the CNp. Leaf CNp greatly decreased when leaves were directly exposed to sunlight. These results allowed us to determine the best leaf sampling conditions for the comparison of leaf CNp. Under these conditions, leaf CNp was found to vary from less than 25mM to more than 60mM. The rubber clones containing the highest leaf CNp were those with the highest yield potential. In mature virgin trees, the CNp of the trunk inner bark was shown to be proportional to leaf CNp and to decrease on tapping. However, the latex itself exhibited very low (if any) CNp, while harboring all the enzymes (β-d-diglucosidase, linamarase and β-cyanoalanine synthase) necessary to metabolize cyanogenic glucosides to generate non-cyanogenic compounds, such as asparagine. This suggests that in the rubber tree bark, cyanogenic glucosides may be a source of buffering nitrogen and glucose, thereby contributing to latex regeneration/production. [Copyright &y& Elsevier]

Abstract: From the stem bark of Pteleopsis hylodendron, a triterpenoidal saponin bellericagenin {B 3-O-[β-d-glucopyranosyl-(1→2)-α-d-glucopyranoside] (1) (Pteleopsoside)} and two sphingolipids, hylodendroside-I (2), and hylodendroside-II (3) were isolated, along with a synthetically known compound, {2α, 3β, 23-triacetoxy-19α-hydroxyolean-12-en-28-oic acid (4)}. Other known compounds, friedelin (5), β-carotene (6), lupeol (7), sitosterol (8), and stigmasterol (9), were also obtained. Their structures were deduced with the help of detailed spectroscopic studies. [Copyright &y& Elsevier]

Abstract: Seven nor- and podocarpane-type diterpenes were isolated from the bark of Taiwania cryptomerioides Hayata, including three 18-nor-podocarpanes: 18-nor-1β,4α,14-trihydroxy-13-methoxy-8,11,13-podocarpatriene (1), 18-nor-1β,4α,13,14-tetrahydroxy-8,11,13-podocarpatrien-7-one (2), 18-nor-1β,4α,14-trihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (3), 1β,14,19-trihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (4), 1β,13,14,18-tetrahydroxy-8,11,13-podocarpatrien-7-one (5), 18-acetoxy-1β,13,14-trihydroxy-8,11,13-podocarpatrien-7-one (6), and 1β,14,18-trihydroxy-13-methoxy-8,11,13-podocarpatrien-7-one (7). Their structures were determined by application of 1D and 2D NMR spectroscopy and other techniques. Podocarpane-type diterpenes do not occur extensively in nature, and the presumed oxidative enzyme in this plant will be of interest to identify. [Copyright &y& Elsevier]

Abstract: As part of a long-term study of the chemical defenses of Norway spruce (Picea abies) against herbivores and pathogens, a phytochemical survey of the phenolics in the bark was carried out. Eight stilbene glucoside dimers, designated as piceasides A–H (1a–4b), were isolated as four 1:1 mixtures of inseparable diastereomers. Their structures were determined by extensive spectroscopic means including 1D (1H and 13C) and 2D NMR (1H–1H COSY, HSQC, HMBC, ROESY) spectra, and were supported by enzymatic hydrolysis and computational analysis. [Copyright &y& Elsevier]

Abstract: Phytochemical investigations of the MeOH extract of Betula papyrifera inner bark led to the isolation of ten phenolic compounds of the following types: diarylheptanoid glycosides (1–4), a diarylheptanoid (5), a lignan (6), flavonoids (7–8) and chavicol glycosides (9–10). Among them, the diarylheptanoid glycoside, (S)-1,7-bis-(4-hydroxyphenyl)-heptan-3-one-5-O-α-l-arabinofuranosyl-(1→6)-β-d-glucopyranoside, papyriferoside A (1), was isolated and its structure was determined on the basis of 1D and 2D NMR, HPLC-MS, as well as high resolution mass spectroscopic data. Platyphylloside (4) exerted the strongest cytotoxic activity of all isolated compounds with IC50 values ranging from 10.3 to 13.8μM. [Copyright &y& Elsevier]

Abstract: Bioactivity-guided fractionation of the light petroleum extract of Caesalpinia benthamiana (=Mezoneuron benthamianum) root bark has led to the isolation of two cassane diterpenoids, designated as benthaminin 1 and 2. A third compound, a deoxy form of caesaldekarin C (also referred to as methyl vouacapenate) which has previously been isolated from Caesalpinia major, C. bonducella, Vouacapoua americana and V. macropetala, was also isolated, together with β-sitosterol and stigmastenone. The antibacterial and antioxidant activities of these cassane diterpenoids have been assessed using the microdilution assay method and DPPH spectrophotometric and TBA lipid peroxidation assays. Benthaminin 1 was the more active antibacterial compound with MIC values of 47.8μM for both Staphylococcus aureus and Micrococcus flavus. Benthaminin 2 was the more active antioxidant compound and showed IC50 values of 42.7μM and 74.2μM for the DPPH and TBA assays, respectively. Deoxycaesaldekarin C possessed both antibacterial and antioxidant activities. The presence of methyl ester and methyl functional groups as well as an unsaturated furan ring appears to confer antibacterial activity. On the other hand, the relatively stronger antioxidant activity of benthaminin 2 may be associated with the presence of an exocyclic methylene function. [Copyright &y& Elsevier]