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One new nucleoside 1 and three new furanpentone derivatives 2‒4 were isolated from the aerial part of Rubia cordifolia. Their structures were established using spectroscopic methods. Compounds 1 and 4 exhibited inhibition of NO production with IC50 values of 27.5 and 19.8 μM, respectively.

Six new compounds, xylomexicanins K-N (

Six new compounds, xylomexicanins K-N (1–4), granasteroid (5) and 5-methoxy-2-pentylbenzofuran-7-ol (6), along with nine known compounds were isolated from the leaves and twigs of Xylocarpus granatum. Among them, 1 was a biogenetic precursor of 1,8,9-phragmalin limonoid, and 4 represent the first example of degraded A-ring limonoid. The structures of them were elucidated on the basis of one- and two-dimensional NMR spectroscopic data (including 1H, 13C-NMR, DEPT, 1H-1H COSY, HSQC, HMBC, and NOESY) and confirmed by high-resolution mass spectrometry.

Two tetranortriterpenoids with new skeletons, xylomexicanins I and J (1 and 2), were isolated during the investigation of chemical constituents from seeds of the Chinese mangrove, Xylocarpus granatum. Xylomexicanin I (1) is an unprecedented limonoid with bridged B- and C-rings. A biosynthesis pathway for 1 from xylomexicanin F is proposed.

The genus Neolitsea (Lauraceae) contains over 85 species distributed around the world. These plants have been found to be rich in sesquiterpenes, triterpenes, steroids, and alkaloids. This review summarizes the phytochemical progress and list of all the constituents isolated from the genus Neolitsea over the past few decades. Some biological activities of compounds isolated from this genus are also included.

An ultrasensitive method for the simultaneous determination of dopamine (DA), uric acid (UA), guanine (G), and adenine (A) was developed using differential pulse voltammetry with a three-dimensionally distributed Au nanoparticle (GNP)-modified glassy carbon electrode (GCE). The nano-Au/DNA/nano-Au/poly(SFR)/GCE microstructure was characterized by scanning electron microscopy, electrochemical impedance spectroscopy, and atomic force microscopy, showing an anchored three-dimensional distribution of GNPs on the modified electrode. The electrode exhibited ultrasensitive responses to DA, UA, G, and A due to poly(SFR) electrocatalytic activities and the large surface area of the GNPs. All four analytes showed well-defined catalytic oxidation peaks at the modified electrode. DA, UA, G, and A yielded linear ranges from 8.0 × 10−9 M to 1.1 × 10−6 M, 9.0 × 10−8 M to 1.2 × 10−5 M, 9.0 × 10−9 M to 5.0 × 10−6 M, and 6.0 × 10−8 M to 8.0 × 10−7 M, respectively, and detection limits for the analytes were 2.0 × 10−10 M, 8.0 × 10−9 M, 5.0 × 10−10 M, and 4.0 × 10−9 M, respectively. The feasibility of the proposed assay for use in human serum and urine was investigated and satisfying results were obtained.

Torreyanoxane, a novel 3,4-secoglutinane triterpenoid, was isolated from the pulp of Torreya nucifera. The structure was determined on the basis of spectroscopic methods.

Ten 1,10-secoguaianolides were isolated from the flowers of Achillea millefolium. Their structures were determined on the basis of spectroscopic methods. Three of them (millifolides A-C) including two dimeric sesquiterpenoids exhibit new skeletons. Seco-tanapartholide A exhibited moderate cell growth inhibitory activity against the human cancer cell line MCF7WT (IC50 = 5.51 μm) in vitro.

Zhi-Yu Nia, Yi-Bing Wub, Mei Donga, Man-Li Zhangb, Yu-Fang Wangb, Francoise Sauriolc, Chang-Hong Huob, Qing-Wen Shib,d, Yu-Cheng Gub,e, Hiromasa Kiyotaf, and Bin Conga,d a College of Basic Medicine, Hebei Medical University, Shijiazhuang, 050017, Hebei Province, P. R. China b School of Pharmaceutical Sciences, Hebei Medical University, Shijiazhuang, 050017, Hebei Province, P. R. China c Department of Chemistry, Queen’s University, Kingston, Ontario, K7L 3N6, Canada d Hebei Key Laboratory of Forensic Medicine, Shijiazhuang, 050017, Hebei Province, P.R. China e Syngenta Jealott’s Hill International Research Centre, Bracknell, Berkshire, RG42 6EY, UK f Graduate School of Agricultural Science, Tohoku University, Aoba-ku, Sendai 981-8555, Japan

Voltage-gated Kv7/KCNQ/M-potassium channels play a pivotal role in controlling neuronal excitability. Genetic reduction of KCNQ channel activity as a result of mutations causes various human diseases such as epilepsy and arrhythmia. Therefore, discovery of small molecules that activate KCNQ channels is an important strategy for clinical intervention of membrane excitability related disorders. In this study, a series of pyrazolo[1,5-a]pyrimidin-7(4H)-ones (PPOs) have been found to be novel activators (openers) of KCNQ2/3 potassium channels through high-throughput screening by using atomic absorption rubidium efflux assay. Based on structure-activity relationship (SAR), the substituted PPOs have been optimized. The 5-(2,6-dichloro-5-fluoropyridin-3-yl)-3-phenyl-2-(trifluoromethyl) pyrazolo[1,5-a]pyrimidin-7(4H)-one (17) was identified as a novel, potent, and selective KCNQ2/3 potassium channel opener by patch-clamp recording assay.

To determine the chemical constituents responsible for pharmacological effects of Inula britannica-F., three specific sesquiterpene lactones in Inula britannica were isolated from chloroform extract and identified, including britannilactone (BL), 1-O-acetylbritannilactone (ABLO), and 1,6-O,O-diacetylbritannilactone (ABLOO). Electrophoretic mobility shift assay (EMSA) was performed to detect the nuclear translocation of nuclear factor-kappaB (NF-kappaB) p65. The expressions of IkappaBalpha, pIkappaBalpha, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), IkappaB kinase alpha/beta (IKKalpha/beta) and NF-kappaB kinase (NIK) were detected by Western blot and RT-PCR. We found that acetyl side groups enhanced the inhibitory action of the agents on LPS/IFN-gamma-induced iNOS and COX-2 expression. Their inhibiting activity was positive correlation with the acetyl side group number. The effects of LPS/IFN-gamma were reversed by ABLOO, and BL without acetyl side groups showed only a weak inhibitory action. Further study indicated that ABLOO markedly inhibited the phosphorylation of IKKbeta down to based level, but not IKKalpha, corresponding with decreased in IkappaBalpha degradation and phosphorylation induced by LPS/IFN-gamma, resulting in the suppression of NF-kappaB nuclear translocation and activity. These results suggest that the acetyl moieties add to the lipophilicity, and consequently enhance cellular penetration, so that ABLOO possess the most anti-inflammatory effect and may be a potent lead structure for the development of therapeutic and cytokine-suppressing remedies valuable for the treatment of various inflammatory diseases.

A reversed-phase high-performance liquid chromatographic method was developed for the first time to simultaneously determine six major sesquiterpene lactones in Inula britannica L, that is, britannilactone, 1-O-acetylbritannilactone, hydroxylantolactone, 8-epi-ivangustin, 6-isobutylbritannilactone and 1,6-O,O-diacetylbritannilactone. The chromatographic separation was achieved with a linear gradient of acetonitrile in water with a flow rate at 1.0 mL min−1 using an Inertsil ODS-3 column (250 × 4.6 mm, 5.0 μm). Detection was carried out using a photodiode array detector at 210 nm. The calibration curves for the determination of all analytes showed good linearity over the investigated ranges (R 2 > 0.999). Repeatability was evaluated by intra-day and inter-day assays and RSD values were less than 3.0%. The recoveries were between 93.9 and 104.6%. This developed method can be used for quality control purposes and allows for the differentiation between Inula britannica L., Inula hupehensis Ling., and Inula japonica Thunb.

To study the chemical constituents in the bark of Taxus chinensis var. mairei collected from southeast of China.Chemical constituents were isolated and purified by column chromatography, Prep-TLC, and preparative HPLC. The structures were identified on the basis of 1D-and 2D-NMR spectral analysis.Twelve taxane diterpenoids were isolated from the bark of Taxus chinensis var. mairei grown in southeast of China. They were identified as: taxagifine (1), decinnamoyltaxagifine (2), 19-debenzoyl-19-acetyltaxinine M(3), 9-dihydro-13-acetyl-baccatin III (4), 7, 9-dideacetylbaccatin IV (5), 1,3-dihydro-taxinine (6), taxumairol C (7), taxezopidine J (8), 7-xylosyl-10-deacetyl-taxol A (9),10-deacetyltaxol (10), taxicin II (11), and 2alpha, 7beta, 10beta-triacetoxy-5alpha, 13alpha-dihydroxy-2 (3 --20) abeotaxa-4 (20), 11-dien-9-one (12).Compounds 1, 2, 4 - 6, 8, 9, 11 and 12 are obtained from this plant for the first time. Compound 7 is obtained from the bark of Taxus chinensis var. mairei for the first time.

A new sesquiterpene, eudesm-11-ene-4alpha,7beta,9beta-triol, was isolated from the EtOH extract of aerial parts of Dichrocephala integrifolia. Its structure was determined on the basis of spectral analysis of 1D and 2D NMR data.

To study the chemical constituents in the needles of Taxus cuspidata collected from Japan.Chemical constituents were isolated by column chromatography, TLC and preparative HPLC. The structures were identified on the basis of NMR spectral analysis.Six non-taxoids were isolated and identified as: 4-[(1E)-3-hydroxy-1-buten-1-yl]-3,5,5-trimethyl-2-cyclohexen-1-one (1), megastigm-5-ene-3, 9-diol (2), 6alpha-epoxy-7-megastigmen-9-one (3), 4-(4-hydroxyphenyl)-2-butanone (4), 12-hydroxy-alpha-cyperone (5), scutellarein-7-O-alpha-L-rhamnoside (6).Compounds 2 - 6 are isolated from Taxus genus for the first time. Compound 1 is obtained from Taxus cuspidata for the first time.

Two new limonoids, named xylomexicanins C and D, were isolated from a dichloromethane extract of the seeds of Xylocarpus granatum cultivated in Hainan, China, and their structures were elucidated on the basis of one- and two-dimensional NMR (including 1H, 13C-NMR, DEPT, 1H-1H COSY, HSQC, HMBC, and NOESY) and confirmed by high-resolution mass spectrometry. Xylomexicanin C exhibited antiproliferative activity against human breast carcinoma cells (KT).

A novel 6/8/6-membered taxane with a rare C-12(13)-double bond and rare 2(3→20)abeotaxane were isolated from the needles of Taxus canadensis. Their structures were characterized as 7β,9α,10β-triacetoxytaxa-4(20),12-diene-2α,5α,11β-triol (1) and 2α,7β,10β-triacetoxy-5α-hydroxy-2(3→20)abeotaxa-4(20),11-diene-9,13-dione (2) on the basis of 1D and 2D spectroscopic data. 1 is the first example of a natural taxane without substitution at both C-13 and C-14.

To determine the chemical constituents responsible for pharmacological effects of Inula britannica-F., three specific sesquiterpene lactones in Inula britannica were isolated from chloroform extract and identified, including britannilactone (BL), 1-O-acetylbritannilactone (ABLO), and 1,6-O,O-diacetylbritannilactone (ABLOO). Electrophoretic mobility shift assay (EMSA) was performed to detect the nuclear translocation of nuclear factor-kappaB (NF-kappaB) p65. The expressions of IkappaBalpha, pIkappaBalpha, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), IkappaB kinase alpha/beta (IKKalpha/beta) and NF-kappaB kinase (NIK) were detected by Western blot and RT-PCR. We found that acetyl side groups enhanced the inhibitory action of the agents on LPS/IFN-gamma-induced iNOS and COX-2 expression. Their inhibiting activity was positive correlation with the acetyl side group number. The effects of LPS/IFN-gamma were reversed by ABLOO, and BL without acetyl side groups showed only a weak inhibitory action. Further study indicated that ABLOO markedly inhibited the phosphorylation of IKKbeta down to based level, but not IKKalpha, corresponding with decreased in IkappaBalpha degradation and phosphorylation induced by LPS/IFN-gamma, resulting in the suppression of NF-kappaB nuclear translocation and activity. These results suggest that the acetyl moieties add to the lipophilicity, and consequently enhance cellular penetration, so that ABLOO possess the most anti-inflammatory effect and may be a potent lead structure for the development of therapeutic and cytokine-suppressing remedies valuable for the treatment of various inflammatory diseases.

A new sesquiterpene, eudesm-11-ene-4α,7β,9β-triol, was isolated from the EtOH extract of aerial parts of Dichrocephala integrifolia. Its structure was determined on the basis of spectral analysis of 1D and 2D NMR data.

Experimental Advanced Superconducting Tokamak (EAST), a National Mage project of Science Research of China, is a very important fusion experiment facility. The ability of magnetic confinement to plasma can be improved by elongating plasma cross section in EAST. However, elongated plasma has vertical displacement instability; without control, plasma will dash against a wall of vacuum vessel and disrupt, which will cause failure of plasma discharge. Therefore, a feedback control system is needed to restrain plasma vertical displacement. Fast control power supply excites active feedback coils, which produces magnetic field to control plasma's displacement. With the development of EAST, the power supply needs to keep on enhancing the ability of fast response and output current. The structure and control method of the new power supply are introduced in this paper. The technique of carrier-wave phase-shift pulsewidth modulation is applied to raise equal switch frequency of converter and improve performance of output wave. The analysis of harmonic and the simulation are carried out, the validity of the proposed scheme and control strategy are confirmed by experiments, and the power supply system can supply large current and has the ability of fast response.