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Purpose Based on the aerodynamic loads and dynamic performances of trains, this study aims to investigate the effect of crosswinds and raindrops on intercity trains operating on viaducts to ensure the safe operation of intercity railways in metropolitan areas. Design/methodology/approach An approach coupled with the Euler multiphase model as well as the standard k-ɛ turbulence model is used to investigate the coupled flow feature surrounding trains and viaducts, including airflow and raindrops, and the numerical results are validated with those of the wind tunnel test. Additionally, the train’s dynamic response and the operating safety region in different crosswind speeds and rainfall is investigated based on train’s aerodynamic loads and the train wheel–rail dynamics simulation. Findings The aerodynamic loads of trains at varying running speeds exhibit an increasing trend as the increase of wind speed and rainfall intensity. The motion of raindrop particles demonstrates a significant similarity with the airflow in wind and rain environments, as a result of the dominance of airflow and the supplementary impacts of droplets. As the train’s operating speed ranged between 120 and 200 km/h and within a rainfall range of 20–100 mm/h, the safe operating region of trains decreased by 0.56%–7.03%, compared with the no-rain condition (0 mm/h). Originality/value The impact of crosswind speeds and rainfall on the train’s aerodynamic safety is studied, including the flow feature of crosswind and different particle-sized raindrops around the train and viaduct, aerodynamic loads coefficients suffered by the intercity train as well as the operating safety region of intercity trains on the viaduct.

Purpose This paper aims to investigate the variations in the flow fields induced by transition regions in the windbreak structures between the flat ground and the cutting along a railway and to propose mitigation measures to improve the windproof ability of the windbreak. Design/methodology/approach The improved delayed detached eddy simulation method was used to simulate the impact of the windbreak transition on flow structures of the high-speed railway under different wind angles, and also the accuracy of the numerical results was validated with those of the wind tunnel test. Findings The results showed that the original windbreak transition region resulted in a dimensionless peak wind velocity of 0.62 and 0.82 for railway line-1 at wind angles of 90° and 75°, respectively, and the corresponding values were 0.81 and 0.97 for railway line-2. The flow structure analysis revealed the reason for the mismatched height in the transition region, and the right-angle structures of the windbreaks resulted in ineffective protection and sudden changes in the wind speed and direction. Two mitigation measures – oblique structure (OS) and circular curve structure (CCS) transition walls – were developed to reduce the peak wind speed. The OS provided superior protection. The peak value of dimensionless wind velocity was all less than 0.2 for OS and CCS. Originality/value The flow field deterioration mechanism induced by the inappropriate form of a windbreak transition at different wind angles was examined, and effective mitigation and improvement measures were proposed and compared with the original transition.

Five compounds were isolated from the methanolic extract of

Currently, there is no effective treatment for Burkitt's lymphoma in patients aged above 60 years, and thus research on effective treatment options for Burkitt's lymphoma has been gaining increasing attention. Artesunate has been identified as a novel effective growth suppressor in Burkitt's lymphoma. Here, we utilized molecular biology, transcriptome analysis, and other techniques to study artesunate-induced death of the Burkitt's lymphoma cells DAUDI and CA-46, the effect of artesunate on gene expression in DAUDI and CA-46 cells, and the effect of artesunate-induced ATF4-CHOP-CHAC1 pathway on ferroptosis. We also studied the inhibitory effects and ferroptosis induction of artesunate on CA-46 cells in mouse xenografts. Results showed that artesunate induced ferroptosis in DAUDI and CA-46 cells, as evidenced by the protective effect of liproxstatin-1, ferrostatin-1, and desferoxamine, resulting in an endoplasmic reticulum stress response, a ctivation of the ATF4-CHOP-CHAC1 pathway enhanced ferroptosis in DAUDI and CA-46 cells. A mouse-transplanted tumor model showed that artesunate can inhibit the proliferation and induce ferroptosis of CA-46 cells in vivo. This study provides a novel perspective for the development of drugs against different types of Burkitt's lymphomas.

Garcilancibiphenyls A–C (1–3), three new biphenyls, were isolated from the stems of the plant Garcinia lancilimba, which belongs to the family Clusiaceae. Structures of the new compounds feature the acetoxyprenyl group on a benzene ring, and were elucidated by spectroscopic evidence. These compounds showed promising anti-rotavirus activity effects with TI values above 10.

Ethnopharmacological relevance Rubia yunnanensis is a medicinal plant mainly grown in Yunnan province in Southwest China, and its root named “Xiaohongshen” has been used as a herb in Yunnan for the treatment of cancers. Three major types of chemical components, Rubiaceae-type cyclopeptides, quinones, and triterpenoids, were identified from R. yunnanensis, in which some of compounds including rubiarbonol G (RG), a unique arboriane-type triterpenoid, showed cytotoxicity on cancer cells. But the cytotoxic mechanism of RG has not been reported. Aim of the study To investigate the cytotoxic mechanism of RG on cancer cells. Materials and methods RG was evaluated its cytotoxicity on 7 cancer cell lines by the SRB assay, and detected the effect on apoptosis and cell cycle arrest by Annexin V-FITC/PI apoptosis assay and DNA contents analysis. The expression and activity of apoptosis and cell cycle related proteins were also investigated by western blot and caspase activity assay. Furthermore, the effect of RG on NF-κB signaling was also tested by luciferase assay, western blot, and immunofluorescence staining. Results RG showed potent cytotoxicity on 7 human cancer cell lines, whose activity was attributed to apoptosis induction and G0/G1 arrest in HeLa cells. Results from the mechanism study showed that RG promoted the activation of ERK1/2 and JNK pathway in MAPK family, which in turn increased the expression of p53, thereby triggering the G0/G1 arrest through p53/p21/cyclin D1 signaling. Moreover, RG-mediated JNK activation down-regulated the expression of the anti-apoptotic protein Bcl-2, which caused the release of cytochrome c to the cytosol and activated the cleavage of caspase cascade and poly(ADP-ribose) polymerase, thereby inducing apoptosis in HeLa cells. In addition, RG was also found to inhibit the activation of NF-κB signaling by down-regulating the expression and attenuating the translocation to nucleus of NF-κB p65, by which the down-stream p53, cyclin D1, Bcl-2, and caspases were regulated, thereby triggering apoptosis and G0/G1 arrest in HeLa cells. Conclusion These results indicated that RG induces mitochondria-mediated apoptosis and G0/G1 cell cycle arrest by activation of JNK signaling as well as inactivation of NF-κB pathway in HeLa cells, which suggests that RG is one of the key active ingredients accounting for the anti-tumor effect of R. yunnanensis.

Rubiaceae-type cyclopeptides (RAs) are a type of plant cyclopeptides from the Rubia that have garnered significant attention owing to their unique bicyclic structures and amazing antitumour activities. Our recent work has shown that RAs suppress inflammation and angiogenesis and induce apoptosis. However, the underlying mechanism and targets remained unknown. Nuclear factor κB (NF-κB) signaling pathway plays a critical role in these biological processes, prompting us to investigate whether and how RAs affect this pathway. By screening compound libraries using NF-κB-dependent luciferase reporter, we observed that RA-V is the best NF-κB inhibitor. Further experiments demonstrated that RA-V interrupted the TAK1–TAB2 interaction and targeted TAK1 in this pathway. Moreover, RA-V prevented endotoxin shock and inhibited NF-κB activation and tumor growth in vivo. These findings clarify the mechanism of RA-V on NF-κB pathway and might account for the majority of known bioactivities of RA-V, which will help RA-V develop as new antiinflammatory and antitumour therapies.

Five new quinone derivatives, rubiasins D-F (1-3), rubialatones A and B (4 and 5), have been isolated from the roots and rhizomes of three Rubia species, Rubia alata, R. wallichiana and R. schumanniana, together with 26 known quinones (6-31). Their structures have been elucidated on the basis of NMR, MS spectra and computational methods. The compounds have been evaluated for their toxicity to the saprophytic nematode Caenorhabditis elegans and the root-knot nematode Meloidogyne incognita. Compounds 1, 6 and 7 showed toxicity to C. elegans with the LC50 values at 8.50, 9.44 and 44.82 mu g/mL, respectively; and 6 showed toxicity to M. incognita with the LC50 value at 35.22 mu g/mL. Meanwhile, compounds 1 and 6 showed inhibitory effect on egg hatch of C. elegans with the LC50 values at 5.60 and 48.95 mu g/ml. (C) 2018 Elsevier Ltd. All rights reserved.

A novel sesquiterpenoid, named Cyperensol A (1), was isolated from the rhizomes of Cyperus rotundus L. Its structure was elucidated extensively by the spectroscopic analysis. Possible biosynthetic pathway of 1 was proposed. Compound 1 showed inhibitory activity on IL-6 induced activation of JAK/STAT3 signaling pathway with IC50 value of 189.37 ± 7.20 μM.

The chemical constituents from methanol extract of Dichroa hirsuta were separated by silica gel and Sephadex LH-20 column chromatography,high pressure preparative liquid chromatography( HPLC) and recrystallization. Their structures were elucidated by NMR and MS. Nine compounds were obtained and their structures were identified as 3β,21α-O-diacetyl-lup-9( 11)-en-7β-ol( 1),( Z)-methyl p-hydroxycinnamate( 2),cis-p-coumaric acid ethyl ester( 3),( E)-methyl p-hydroxycinnamate( 4),trans-p-coumaric acid ethyl ester( 5),4( 3 H)-quinazolinone( 6),7-hydroxycoumarin( 7),hydrangenol( 8) and thunberginol C( 9). Compound 1 is a new lupane-type triterpenoid,and compounds 1-5,8-9 were firstly isolated from this plant. Dual reporter assay results showed that compounds 2-5 could activate the Nrf2-ARE signaling pathway.

A total of ten compounds were isolated from the 90% Et OH extract of Cassia siamea by using various chormatographic techniques,and their structures were established as( 2' S)-2-( propan-2'-ol)-5,7-dihydroxy-benzopyran-4-one( 1),chrobisiamone( 2), 2-( 2'-hydroxypropyl)-5-methyl-7-hydroxychromone( 3), 2,5-dimethyl-7-hydroxychromone( 4), 2-methyl-5-acetonyl-7-hydroxychromone( 5),3-O-methylquercetin( 6),3,5,7,3',4'-pentahydroxyflavonone( 7),luteolin-5,3'-dimethylether( 8),4-( trans)-acetul-3,6,8-trihydroxy-3-methyl-dihydronapht halenone( 9) and 6-hydroxymellein( 10) based on the spectroscopic data.Compound 1 was a new compound,and 3,4,6,8 were isolated from this plant for the first time.

Introduction The genus Quassia is a promising source of secondary metabolites with biological potential including antimalarial and cytotoxic activities. Limited data are available on the phytochemistry and pharmacology of Quassia silvestris Cheek & Jongkind, a Cameroonian medicinal plant used to treat various ailments. Objectives To carry out the bioassay-guided fractionation and LC-HR-ESI-MS analyses of the leaves extract from Q. silvestris; to purify the active fractions and isolate the major compounds using different chromatographic and spectroscopic methods. The obtained compounds will be evaluated for their biological activity. Material and methods Following the cytotoxic screening and LC-HR-ESI-MS profiling of fractions obtained from partition of the methanolic extract of Q. silvestris leaves, the CH2Cl2-soluble fraction which exhibited the highest cytotoxicity was retained for further investigations. Results Sixteen squalene-derived metabolites were identified with oxasqualenoid derivatives being the most predominant. Among the isolates, structure elucidation of two new oxasqualenoids quassiols E (1) and F (2), were achieved by NMR (one-dimensional (1D) and two-dimensional (2D)) and MS methods. The newly characterised compounds 1 and 2, together with the known tetraol (3) and 3-oxo-oleanoic acid (16) displayed moderate cytotoxicity. Conclusion The identification and structural characterisation of highly oxidised squalene derived metabolites from this plant may provide important insight data for further pharmacological investigations. The LC-HR-ESI-MSn method reported here could be developed as a rapid and efficient tool for the analyses of structurally related compounds in the genera Quassia, Simarouba, and Eurycoma of the subfamily Simarouboideae. Copyright © 2016 John Wiley & Sons, Ltd.

Fourteen compounds, including rubiprasin D (1), rubiprasin B (2), rubiprasin C (3), oleanolic acid (4), methyl-5-hydroxy-dinaphtho[1, 2-2'3']furan-7, 12-dione-6-carboxylate (5), rubioncolin C (6), mollugin (7), furomollugin (8), 3-amino-2-methoxycarbonyl-1, 4-naphthoquinone (9), 1-hydroxy-2-methyl-9, 10-anthraquinone (10), 2-hydroxy-6-methyl-9, 10-anthraquinone (11), 1, 4-dihydroxy-2-hydroxymethyl-9, 10-anthraquinone (12), 2-hydroxy-1-methoxy-9, 10-anthraquinone (13), and 1-hydroxy-2-methoxy-6-methyl-9, 10-anthraquinone(14), were isolated from the methanol extract of the roots and rhizomes of Rubia oncotricha using various column chromatographies. Their structures were mainly determined on basis of NMR and MS spectroscopic data analyses. Among them, 1 is a new oleanane triterpene, and compounds 2-5, 9 and 11-13 were obtained from this plant for the first time. Cytotoxic and nematicidal activities of all these compounds were evaluated, and the results showed that only 4, 6, 11 and 12 exhibited cytotoxicities against A549, SGC-7901 and HeLa cancer cell lines. The IC₅₀ of 6 were 19.42, 2.74, 8.07 μmol·L⁻¹, respectively.

To further investigate on the structure-activity relationships of immunosuppressive Astin C, seventeen analogues 1-17 were designed and synthetized via amino acid substitution strategy by the solid-phase peptide synthesis method for the first time. In comparison with Astin C (IC50 = 12.6 ± 3.3 μM), only compounds 2 (IC50 = 38.4 ± 16.2 μM), 4 (IC50 = 51.8 ± 12.7 μM), 5 (IC50 = 65.2 ± 15.6 μM), and 8 (IC50 = 61.8 ± 12.4 μM) exhibited immunosuppressive activity in the Lymph node cells of mice. These results showed that the Astin C analogues containing D-amino acid residues, hydrophobic long-chain alkyl substituents, and aryl substituents performed better than those carrying hydrophilic amino acid residues and short-chain alkyl substituents. Moreover compounds 15, 16, and 17 had no immunosuppressive activity, which suggested that cis-3,4-dichlorinated proline played an important role in the immunosuppressive activity of Astin C.

Three new labdane diterpenes, hedylongnoids A (1), B (2) and C (3), were isolated from the rhizomes of Hedychium longipetalum, together with three known ones yunnancoronarin A (4), hedyforrestin C (5) and hedyforrestin B (6). Their structures were established by spectroscopic analysis, including 2D-NMR spectroscopic techniques. Compounds 1-6 exhibited inhibitory effects against nitric oxide (NO) production in LPS and IFN-gamma-induced RAW 264.7 murine macrophages with IC50 values ranging from 0.56 to 7.50 mu g/ml, and 3-6 showed cytotoxicities against cancer cell lines SGC-7901 and Hela with IC50 values ranging from 6.21 to 14.53 mu g/ml and from 6.58 to 14.83 mu g/ml, respectively. (C) 2015 Elsevier Ltd. All rights reserved.

A new cyclopentapeptide dianthin I (1), together with two known ones pseudostellarin A (2) and heterophyllin J (3), was isolated from the aerial parts of Dianthus chinensis. The structure of 1 was elucidated as cyclo-(Gly(1)- l-Phe(2)- l-Pro(3)- l-Ser(4)- l-Phe(5)) on the basis of extensive spectroscopic analyses and chemical methods. Copyright (c) 2015 European Peptide Society and John Wiley & Sons, Ltd.

Bioassay guided fractionation of Hypericum riparium leaves extract has resulted in the isolation and characterization of three new compounds namely chipericumin E (1), hyperenone C (3), and hyperixanthone (5), together with twenty known compounds. Their structures were elucidated based on comprehensive interpretation of spectroscopic and spectrometric data. Compounds 1-4, and 6-8 displayed moderate antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and cytotoxic effects on the human gastric cell line BGC-823 with IC50 values ranging from 6.54 to 18.50μM.

A new sesquiterpene, hedyunchene A (1), was isolated from the rhizomes of Hedychium yunnanense, together with two known compounds 6β-hydroxystigmasta-4,22-dien-3-one (2) and 6β-hydroxystigmast-4-en-3-one (3). Their structures were determined on the basis of NMR (1D and 2D) and mass spectroscopic analysis.

Rubia yunnanensis is a medicinal plant mainly grown in Yunnan province in Southwest China, and its root named "Xiaohongshen" has been used as a herb in Yunnan for the treatment of cancers. Three major types of chemical components, Rubiaceae-type cyclopeptides, quinones, and triterpenoids, were identified from R. yunnanensis, in which some of compounds including rubiarbonol G (RG), a unique arboriane-type triterpenoid, showed cytotoxicity on cancer cells. But the cytotoxic mechanism of RG has not been reported.To investigate the cytotoxic mechanism of RG on cancer cells.RG was evaluated its cytotoxicity on 7 cancer cell lines by the SRB assay, and detected the effect on apoptosis and cell cycle arrest by Annexin V-FITC/PI apoptosis assay and DNA contents analysis. The expression and activity of apoptosis and cell cycle related proteins were also investigated by western blot and caspase activity assay. Furthermore, the effect of RG on NF-κB signaling was also tested by luciferase assay, western blot, and immunofluorescence staining.RG showed potent cytotoxicity on 7 human cancer cell lines, whose activity was attributed to apoptosis induction and GThese results indicated that RG induces mitochondria-mediated apoptosis and G

Plant-parasitic nematodes are destructive pathogens causing enormous economic losses worldwide. With the withdrawal of fumigants, organophosphates and carbamates, pathogenic nematode control is more difficult. Phytochemicals are the plant secondary metabolites and are friendly for men and the environment. For developing new nematocidal candidates, we screened 790 phytochemicals using the model organism Caenorhabditis elegans and found 10 active compounds, 3 of which were further evaluated for their inhibitory activities against egg hatching of C. elegans and J2 Meloidogyne incognita. Among them, 1,4-naphthoquinone (1,4-NQ) was the only compound that could kill more than 50% of targets at 50 μg/mL, prompting us to investigate how 1,4-NQ triggers nematode lethality. In C. elegans, we observed that 1,4-NQ could influence reactive oxygen production, superoxide dismutase activity, and the heat-shock transcription factor (HSF)-1 pathway, which indicated that 1,4-NQ stimulated significant oxidative stress. Furthermore, using quantitative RT-PCR and transgenetic nematodes, we revealed that 1,4-NQ lethality was related to the Insulin/IGF signaling (IIS) pathway, and the effect of 1,4-NQ on IIS pathway related genes indicated that 1,4-NQ could activate this pathway and suppress the expression of DAF-16 target genes. The triggering of oxidative stress and activation of the IIS pathway indicated that 1,4-NQ operates through the generation of oxygen radicals, which can be lethal to C. elegans, thus making it an interesting lead compound for the development of future nematocides.

Acorus tatarinowii Schott (Shi Chang Pu) belongs to the family of Acoraceae. The plant is used as an important herb for prolonging life many years in traditional Chinese medicine. It is an ancient herbal tonic nutriment and can be used as anti-fatigue medicine. However, the effects of Acorus tatarinowii Schott on the endurance exercise in relation to central nervous system have not yet been clarified. In this study, the effects of Acorus tatarinowii Schott on treadmill running endurance, 5-HT concentrations, TPH2, 5-HT1B expression in the dorsal raphe of exercised rats were investigated.Sixty adult male Sprague-Dawley rats were randomly divided into six groups: the normal group, the exercise group, the exercise and the rhizomes of Acorus tatarinowii Schott (ATS)(1mg/kg)-treated group, the exercise and ATS (10mg/kg)-treated group, the exercise and ATS (100mg/kg)-treated group, the exercise and caffeine (10mg/kg)-treated group. The effects of Acorus tatarinowii Schott on endurance exercise were determined by the time to exhaustion during treadmill exercise. The detection of 5-HT concentrations in the dorsal raphe was performed by HPLC analysis. The levels of TPH2, 5-HT1A and 5-HT1B expression were measured by western blot analysis and real-time PCR.We found Acorus tatarinowii Schott could prolong the time to exhaustion in treadmill exercise and suppress the exercise-induced increase of 5-HT synthesis, TPH2 mRNA and protein expression and prevent the exercise-induced decrease of 5-HT1B mRNA and protein expression in the dorsal raphe. Acorus tatarinowii Schott was as effective as caffeine in prolonging the exhaustion time in treadmill running and in decreasing the exercise-induced increase of 5-HT synthesis and TPH2 mRNA and protein expression and in preventing the exercise-induced decrease of 5-HT1B mRNA and protein expression in the dorsal raphe.The results indicated that the effects of Acorus tatarinowii Schott in inhibiting the exercise-induced synthesis of 5-HT and TPH2 expression and in preventing the exercise-induced decrease of 5-HT1B expression in the dorsal raphe might be the anti-fatigue mechanism of Acorus tatarinowii Schott.

Two novel naphthohydroquinone dimers with unprecedented skeletons, rubialatins A (1) and B (2), were isolated from the herbal plant Rubia alata together with their precursor, mollugin (3). The structures were elucidated on the basis of NMR spectra and crystal X-ray diffraction. Compound 1, a racemate, was separated by chiral column chromatography, and the absolute configurations of the enantiomers were determined by the computational methods. Cytotoxicity of 1-3 was evaluated as well as the effect on the NF-κB pathway. Compound (+)-1 showed cytotoxicity and could inhibit NF-κB pathway. Meanwhile, 2 showed cytotoxicity and a synergistic effect with TNF-α on NF-κB activation.

Three new cyclic hexapeptides, designated as rubischumanins A-C (1-3), together with three known ones (4-6) were isolated from the roots and rhizomes of Rubia schumanniana. The structures were elucidated on the basis of extensive spectroscopic analysis. Cytotoxicity of these compounds was evaluated and compounds 1, 2, 4, and 5 showed cytotoxicity against A549, BGC-823, and Hela cell lines. (C) 2014 Elsevier Ltd. All rights reserved.

Five new analogs 4-8 of rubiyunnanin B (1), mainly modified on the tetrapeptide subunit, were synthesized. These agents 4-8 were substituted D-Ala-L-Ala-L-Tyr(OMe)-L-Ala, D-Ala-L-Ala-L-Phe-L-Ala, D-Ala-L-Ala-L-Tyr-L-Ala, D-Ala-L-Ala-L-Pro-L-Ala, and D-Ala-L-Ala-L-Ala for the D-Ala-L-Ala-c-N-Me-Tyr(OMe)-L-Ala tetrapeptide subunit. Unlike the natural product, the synthetic agents 4-8 adopt only a single solution conformation, and the central peptide bond in the cyclodityrosine subunit of compounds 4-8 adopt trans stereochemistry. Cytotoxic activities of analogs 4-8 against three human cancer cell lines including A549, BGC-823, and HeLa were evaluated and all the five synthesized peptides exhibited no effects against the test cell lines. These compounds were also evaluated for their antiinsulin resistance and insulin sensitizing activities and none of them showed activity in these assays. (C) 2014 Elsevier Ltd. All rights reserved.

To investigate the chemical and bioactive constituents from the stems and leaves of Micromelum integerrimum.The chemical constituents were isolated and purified by silica gel, Sephadex LH-20, and HPLC. Their structures were mainly elucidated on the basis of extensive 1D- and 2D-NMR spectroscopy and mass spectrometry. Their cytotoxicity and antimicrobial activities were tested by the SRB and turbidimetric methods, respectively.Two new phenylpropanoids and two known coumarins were obtained, and their structures were identified as microintegerrin A (1), microintegerrin B (2), scopoletin (3), and scopolin (4). All of the compounds were tested for their cytotoxicity against three cancer cell lines (HeLa, A549, and BGC-823) and for antimicrobial activity against the fungus Candida albicans and the bacterium Staphylococcus aureus.Two new phenylpropanoids 1 and 2 were isolated and identified from the stems and leaves of M. intgerrimum. None of the compounds showed cytotoxic or antimicrobial activity at the tested concentration of 20 μg·mL(-1).

Two new anthraquinone dimers, schimperiquinones A (1) and B (2), together with the known 2-hydroxymethylanthraquinone (3), cleomiscosin A (4), oleanolic acid (5) and sitosterol 3-O-beta-D-glucoside (6) were isolated from the stem bark of Pentas schimperi. Their structures were elucidated on the basis of spectroscopic analysis and comparison with published data or by comparison with authentic samples. To the best of our knowledge, it is the first report of cleomiscosin A, a coumarinolignan from the genus Pentas. Compound 2 exhibited in vitro cytotoxicity (IC50 = 33.05 mu M) against the human cancer cell the BGC-823. (c) 2014 Phytochemical Society of Europe. Published by Elsevier B. V. All rights reserved.

Four new sesquiterpenoids, 1α-hydroxymethyl-3β-hydroxy-7,8-dihydro-ionol (1), 1α-hydroxymethyl- 3β-hydroxy-7,8-dihydro-ionol-9-O-β-D-glucopyranoside (2), (1α,5β,7β)-3,10(14)-guaiadien- 11,12-diol (3), and (6S)-13-O-β-D-glucopyranosyl-abscisic acid (4), together with 10 known sesquiterpenoids and 5 diterpenes were isolated from the branches and leaves of Chamaecyparis obtusa var. breviramea f. crippsii. Their structures were mainly determined on the basis of MS, IR, 1D and 2D NMR spectral evidence. Compound 13-epi-toruolsol (17) showed cytotoxicities against BGC-823 and Hela cancer cell lines with IC50 values of 23.0 and 49:9 μM, and compound 3-epitriptobenzene B (19) showed cytotoxicities against BGC-823, Hela and A549 cancer cell lines with IC50 values of 19.1, 30.3 and 24:5 μM, respectively

Six new shionane-type triterpenes, astershionones A-F (1-6), were obtained from the roots and rhizomes of Aster tataricus. Their structures were elucidated on the basis of spectroscopic data, mainly NMR and MS data. The absolute configuration of 1 was determined by single crystal X-ray diffraction analysis and CD analysis. 3 showed inhibitory activity against HBsAg and HBeAg secretion with IC50 values of 23.0 and 23.1 mu M, and cytotoxicity against HepG 2.2.15 cells with a CC50 value of 170.5 mu M. 3 also exhibited inhibitory activity against HBV DNA replication with an IC50 value of 22.4 mu M (C) 2014 Elsevier B.V. All rights reserved.

Two new amides, claulansamides A and B (1 and 2, resp.), together with five known amides, 3-7 and six known quinolones, 8-13, were isolated from the stems and roots of Clausena lansium. Their structures were elucidated on the basis of extensive spectroscopic methods. Their absolute configurations were determined by single-crystal X-ray diffraction technique, CD, and optical rotation. HPLC Chiral separation of 1 afforded two enantiomers, (+)- and (-)-claulansamide A, respectively. Compounds 9, 12, and 13 were isolated from the genus Clausena for the first time. All compounds were evaluated for their cytotoxic activities against A549, BGC-823, and HeLa cancer cell lines. However, only 9 showed cytotoxic activity against A549 cell line with an IC50 value of 46.3 mu M, and 11 against BGC-823 and HeLa cell lines with the IC50 values of 55.0 and 14.7 mu M, respectively.

An investigation of MeOH extract of Embelia schimperi stem led to the isolation of a new resorcinol derivative, 5-(7’Z-pentadecenyl)resorcinol (1), along with the known compounds lupeol (2) and β-sitosterol glucoside (3). The structures of isolated compounds were elucidated using spectroscopic methods. Compound 1 exhibited moderate in vitro cytotoxic activity against human Hela cell line.

During further investigation on the methanol extract of roots and rhizomes of Aster tataricus, six new chlorinated cyclopentapeptides, designated as astins K-P (9-14), together with eight known derivatives, astins A-H (1-8), were isolated. Structures of the new cyclopeptides were established using extensive spectroscopic methods, and the absolute configurations were determined by the advanced Marfey's method. Astin P (14) represents a unique cyclopentapeptide linking as cyclo-(L-Pro (Cl-2)(1)-L-allo-Thr(2)-L-Ser(3)-L-beta-Phe(4)-L-Ava(5)). Astin B(2) showed cytotoxicity against BGC-823 cell with IC50 value of 19.2 mu g/ml. Astin C (3) exhibited cytotoxicity on HCT-116 and BGC-823 cells with IC50 values of 13.4 and 3.3 mu g/ml, respectively. (C) 2013 Elsevier Ltd. All rights reserved.

A new prenylated xanthone, butyraxanthone F (1) together with 20 known compounds were isolated from the leaves of Pentadesma butyracea. Their identification was achieved by spectroscopic means and comparison of the data with literature or by direct comparison on TLC with authentic samples. To the best of our knowledge, this is the first report of 2-hydroxy-2,3-dihydrosqualene (17) from a natural source. Compounds 2-6 and 11-16 were found for the first time in this genus. The antiproliferative activity of the crude extract, fractions and some isolated compounds was evaluated against three human cancer cell lines, BGC-823, Hela and A549. The crude extract, fractions B and C showed weak activities. Globuxanthone (2) and 30-epi-cambogin (7) were found to be the most active compounds on the three cancer cells. The effect of 2 on Hela cells and that of 7 on BGC-823 cells were noteworthy. The antiproliferative potential of allanxanthone A (3), ergosta-4,6,8(14),22-tetraen-3-one (14) and 2-hydroxy-2,3-dihydrosqualene (17) against BGC-823 and Hela cells could be classified as moderate-to-weak. (C) 2013 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.

Momordica cochinchinensis, a Cucurbitaceae plant commonly found in Southeast Asia, has the unusual property of containing both acyclic and backbone-cyclized trypsin inhibitors with inhibitor cystine knot (ICK) motifs. In the current study we have shown that M. cochinchinensis also contains another family of acyclic ICK peptides. We recently reported two novel peptides from M. cochinchinensis but have now discovered four additional peptides (MCo-3-MCo-6) with related sequences. Together these peptides form a novel family of M. cochinchinensis ICK( peptides (MCo-ICK) that do not have sequence homology with other known peptides and are not potent trypsin inhibitors. Otherwise these new peptides MCo-3 to MCo-6 were evaluated for antimalarial activity against Plasmodium falciparum, and cytotoxic activity against the cancer cell line MDA-MB-231. But these peptides were not active. (C) 2012 Elsevier Inc. All rights reserved.

The genus Quassia is a promising source of secondary metabolites with biological potential including antimalarial and cytotoxic activities. Limited data are available on the phytochemistry and pharmacology of Quassia silvestris CheekJongkind, a Cameroonian medicinal plant used to treat various ailments.To carry out the bioassay-guided fractionation and LC-HR-ESI-MS analyses of the leaves extract from Q. silvestris; to purify the active fractions and isolate the major compounds using different chromatographic and spectroscopic methods. The obtained compounds will be evaluated for their biological activity.Following the cytotoxic screening and LC-HR-ESI-MS profiling of fractions obtained from partition of the methanolic extract of Q. silvestris leaves, the CHSixteen squalene-derived metabolites were identified with oxasqualenoid derivatives being the most predominant. Among the isolates, structure elucidation of two new oxasqualenoids quassiols E (1) and F (2), were achieved by NMR (one-dimensional (1D) and two-dimensional (2D)) and MS methods. The newly characterised compounds 1 and 2, together with the known tetraol (3) and 3-oxo-oleanoic acid (16) displayed moderate cytotoxicity.The identification and structural characterisation of highly oxidised squalene derived metabolites from this plant may provide important insight data for further pharmacological investigations. The LC-HR-ESI-MS