牛心朴子草植物农药的化学成分与生物活性研究

在分离鉴定化学组分基础上结合普筛农药活性,发现牛心朴子草提取物中生物碱部位显示抗植物病毒极高活性。通过生物活性跟踪与色谱分离、结构鉴定,确定它是菲并吲哚里西啶生物碱,包括7-脱甲氧基娃儿藤碱(Antofine)(1)和N-氧代-7-脱甲氧基娃儿藤碱(N-Oxideantofine)(2)。其中2是首次从该草分离得到。Antofine(1)是该草抑制植物病毒主要成份;半中枯斑法测定它在10^-^6g/mL浓度的枯斑抑制率达60%,比对照的常用植物病毒抑制剂活性高1～2个数量级。用多种生测方法验证该草生物碱试样抗植物病毒如烟草花叶病毒(TMV)、马铃薯Y病毒(PVY)、芜菁花叶病毒(TuMV)等的生物活性。     

Influence of the anion on stabilization and Coordination of Cu(II) and Cu(I) Complexes with Bis-[2-(4,6-Dimethylpyrimidyl)] Disulphide

Complexes of the type Cu(L? S? S? L)X₂ (X = Cl, Br) and Cu(L? S? S? L)₂X (X = ClO₄, BF₄) were prepared in CHCl₃? MeOH solution from CuX₂ · 6 H₂O (X = Cl, Br, ClO₄, BF₄) and bis-[2-(4, 6-dimethylpyrimidyl)]disulphide (L? S? S? L), and examined in the mid-(4000–250 cm^?1) and far-i.r. (5000–60 cm^?1) regions. Assignments for metal-ligand and metalhalogen vibrations were made. On the basis of these assignments, conductivity measurements and from magnetic moments and visible absorption data, the stereochemistry of the compounds was tentatively inferred. For Cu(L? S? S? L)X₂ (X = Cl, Br) species may be proposed an essentially [CuN₂X₂] in-plane microsymmetry achieved through two pyrimidyl nitrogen atoms of a ligand molecule, to form a seven-membered chelate ring and two halide ions, with probable interaction along the z axis with adjacent molecules. The Cu(L? S? S? L)₂X (X = ClO₄, BF₄) species, may be considered to contain isolated complexes cations, Cu(L? S? S? L) , or polynuclear cationic polymers, Cu_n(L? S? S? L), in which Cu(I) is, probably via N₃S, tetrahedraly coordinated.     

Antioxidant activity of aqueous methanol extracts of Protaetia brevitarsis Lewis (Coleoptera: Scarabaedia) at different growth stages

In this study, we evaluate the antioxidant properties of the various extracts of Protaetia brevitarsis Lewis (Coleoptera: Scarabaedia) at different growth stages. The antioxidant activities of six different extracts from larvae, pupae and imago were measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and singlet oxygen (1O? ). The larval methanol extracts (LME) and imago methanol extracts (IME) displayed the greatest effect in DPPH and ABTS radical scavenging assay, but the activity of water extracts was weaker in the all tested assays. However, LME and IME could be compared to ascorbic acid in 1O? quenching ability (the effective concentrations of 50% 1O? quenching: EC?? 0.174, 0.149 and 0.177?mg?mL?1, respectively). The antioxidant ability of the extracts to scavenge free radicals could significantly change the contents of gallic acid equivalent, an important factor based on the value of R2. The results suggest that our study may contribute to the development of new bioactive products with potential applications to reduce oxidative stress as well as play a vital role in protecting insect organisms against oxidative damage caused by undesirable conditions.     

毛细管区带电泳法测定卷烟中的生物碱

在磷酸缓冲体系中采用毛细管区带电泳法测定卷烟中的生物碱时,检测灵敏度低,分离度差。考察了卷烟中生物碱的 提取条件,分离缓冲溶液的类型、pH值和浓度,卷烟中生物碱测定方法的线性范围、检出限、重现性和回收率。结果发 现,当采用410 mmol/L的酒石酸溶液（pH 2.8）为缓冲体系时,卷烟中生物碱的检测灵敏度和分离度均有明显改善,烟碱 的线性范围为0.06~0.80 mg/L（其他生物碱为0.006~0.10 mg/L）,检出限为0.002~0.01 mg/L,相对标准偏差为2.2%~10%,回收率为87.6%~102%。     

Chemical composition analysis of the essential oil of Melissa officinalis L. from Kurdistan, Iran by HS/SPME method and calculation of the biophysicochemical coefficients of the components

The volatile constituents of the essential oil of wild Melissa officinalis L. obtained from the Kurdistan province of Iran were extracted by headspace/solid-phase micro-extraction and were analysed by gas chromatography and gas chromatography/mass spectrometry. Of a total of 14 compounds in the oil, 12 (85.7%) were identified. The main components were as follows: (E)-citral (37.2%), neral (23.9%) and citronellal (20.3%). Some physicochemical properties, such as the logarithm of calculated octanol-water partitioning coefficients (log?K (ow))(,) total biodegradation (TB (d) in mol?h(-1) and g?h(-1)), water solubility (S (w), mg?L(-1) at 25°C) and median lethal concentration 50 (LC(50)), were calculated for compounds 1-14 from M. officinalis L.     

Asymmetric syntheses of the homalium alkaloids (-)-(s,s)-homaline and (-)-(r,r)-hopromine

The highly diastereoselective conjugate additions of the novel lithium amide reagents lithium (R)-N-(3-chloropropyl)-N-(α-methylbenzyl)amide and lithium (R)-N-(3-chloropropyl)-N-(α-methyl-p-methoxybenzyl)amide to α,β-unsaturated esters were used as the key steps in syntheses of the homalium alkaloids (-)-(S,S)-homaline and (-)-(R,R)-hopromine. The asymmetric synthesis of (-)-(S,S)-homaline was achieved in 8 steps and 18% overall yield, and the asymmetric synthesis of (-)-(R,R)-hopromine was achieved in 9 steps and 23% overall yield, from commercially available starting materials in each case. These syntheses therefore represent by far the most efficient total asymmetric syntheses of these alkaloids reported to date. A sample of the (4'R,4'S)-epimer of hopromine was also produced using this approach, which provided the first unambiguous confirmation of its absolute configuration and therefore that of natural (-)-(R,R)-hopromine.     

Intramolecular,Stoichiometric (Li,Mg, Zn) and Catalytic (Ni,Pd, Pt) Metallo-Ene Reactions in Organic Synthesis [New Synthetic Methods (75)]

Metallo-ene reactions, hardly recognized until very recently, have experienced a breathtaking development when applied in an intramolecular sense. Efficient regio- and stereoselective magnesium-ene cyclizations have served as a cornerstone for numerous syntheses of structurally diverse natural products (e.g., sesquiterpenes of marine or plant origin, alkaloids, fragrances, insect defense compounds, and a fungitoxin). A brilliant example is the synthesis of the elusive odorant (+)-khusimone which outshines 20 years of work in the field of tricyclovetivane synthesis. Palladium-, platinum-, and nickel-catalyzed versions of the metallo-ene reaction are in a comparatively early stage of exploration, but, nevertheless, reveal intriguing potential. Hence an almost 100% stereospecific C? O→C? ;Pd-→ C? C chirality transfer permits simple and selective, cis- or trans-annelation processes. The mild cyclization conditions are compatible with various functional groups, such as nitrogen moieties, which offer interesting perspectives for the preparation of heterocycles (e.g., alkaloids) difficult to obtain by other methods. Carbon monoxide insertion reactions of the cyclized σ-metal intermediates were shown to afford annelated cyclopentanones and cyclopentenones with concomitant stereocontrolled formation of four carbon–carbon bonds. These and other observations, highlighted in this article, provide a platform for further extensions and applications of this powerful method in organic synthesis.     

电堆积在线扫集胶束电动色谱法测定苦参中的生物碱

建立了电堆积在线扫集胶束电动色谱法测定苦参碱和槐定碱的新方法.考察了pH值、磷酸二氢钠浓度、CTAB浓度、电压、有机溶剂和进样时间对分离效果的影响.采用未涂层熔融石英毛细管,以20mmol/L磷酸二氢钠-0.8 mmol/L CTAB-100mmol/L Tris(含10%异丙醇,pH 8.9)为缓冲液,在进样电压-1...     

Determination of quinolizidine alkaloids in traditional Chinese herbal drugs by nonaqueous capillary electrophoresis.

A rapid method for the determination of quinolizidine alkaloids by nonaqueous capillary electrophoresis was developed. A total of 10 alkaloids (matrine, sophocarpine, oxymatrine, oxysophocarpine, sophoridine, cytisine, sophoramine, aloperine, lehmannine and dauricine) could be easily separated within 18 min. A running buffer composed of 50 mM ammonium acetate, 10% tetrahydrofuran and 0.5% acetic acid in methanol was found to be the most suitable for this separation. Five of these alkaloids were selected for further studies. The linear calibration ranges were 2.51-50.1 microg/ml for sophoridine and sophocarpine, 2.71-54.2 microg/ml for matrine, 3.30-65.9 microg/ml for oxymatrine, and 3.10-62.0 microg/ml for oxysophocarpine. The recovery of the five alkaloids was 98.0-101.3% with relative standard deviations from 1.03 to 2.68% (n=5). The limits of detection for all 10 alkaloids were over the range 0.93-2.31 microg/ml. The method was successfully applied to the phytochemical analysis of alkaloid extracts from three commonly used traditional Chinese herbal drugs: Sophora flavescens Ait. (Kushen), S. alopecuroides L. (Kudouzi or Kugancao) and S. tonkinensis Gapnep (Shandougen).     

Ethanolic extract of Rubia peregrina L. (Rubiaceae) inhibits haloperidol-induced catalepsy and reserpine-induced orofacial dyskinesia

In the traditional Sardinian system of medicine, Rubia peregrina L. (Rubiaceae) is reported as an aphrodisiac herb. Since the aphrodisiacs may also have antioxidant and dopaminergic activities, the aim of this study was to study the effect of ethanolic extract of aerial parts of R. peregrina for the scavenging of free DPPH radicals and the inhibition of haloperidol-induced catalepsy in mice and reserpine-induced orofacial dyskinesia in rats. The extract exhibited significant antioxidant activity in a free radical DPPH assay with IC(50)?=?55.6?μg?mL(-1), which was very close to IC(50) of ascorbic acid. The extract of R. peregrina (100 and 200?mg?kg(-1) intraperitoneally, i.p.) significantly inhibited haloperidol (1?mg?kg(-1) i.p.) - induced catalepsy in mice (p?相似文献   

Methyl jasmonate influence on silymarin production and plant stress responses in Silybum marianum hairy root cultures in a bioreactor

In this article our aim was to evaluate mass cultivation of S. marianum hairy roots in a bioreactor to produce silymarin. The effects of methyl jasmonate (MJ) elicitation on the accumulation of silymarin and the extent of the MJ-induced oxidative damage were investigated in bioreactor hairy root cultures of S. marianum. The growth rate of the bioreactor hairy root cultures was higher than that of those in a shake flask after 3 weeks. Silymarin accumulation was increased from 0.13?mg?g?1 DW in non-treated hairy roots to 0.22?mg?g?1 DW in hairy roots 72?h after 100?μM?MJ treatment. Guaiacol peroxidase and ascorbate peroxidase were activated by MJ?72?h after treatment, being 3.2- and 1.3-fold higher, respectively, than that of the control. An increase in enzymatic activity suggests increased scavenging of reactive oxygen species, indicating the tolerance to MJ stress. These results suggest that MJ elicitation is beneficial for silymarin production using bioreactor hairy root cultures.     

Acetylcholinesterase and butyrylcholinesterase inhibitory compounds from Chelidonium majus (Papaveraceae)

The roots and aerial parts of Chelidonium majus L. were extracted with EtOH and fractionated using CHCl3 and EtOH. Repeated column chromatography, preparative TLC and crystallization led to the isolation of five isoquinoline alkaloids, stylopine (3), chelidonine (4), homochelidonine (5), protopine (6), and allocryptopine (7), along with two isolation artifacts 6-ethoxydihydrosanguinarine (1) and 6-ethoxydihydrochelerythrine (2). All isolated compounds were tested for human blood acetylcholinesterase (HuAChE) and human plasma butyrylcholinesterase (HuBuChE) inhibitory activity. The isolation artifacts exhibited the highest activity against HuAChE and HuBuChE with IC50 values of 0.83 +/- 0.04 microM and 4.20 +/- 0.19 microM for 6-ethoxydihydrochelerythrine and 3.25 +/- 0.24 microM and 4.51 +/- 0.31 microM for 6-ethoxydihydrosanguinarine. The most active of the naturally-occurring alkaloids was chelidonine, which inhibited both HuAChE and HuBuChE in a dose-dependent manner with IC50 values of 26.8 +/- 1.2 microM and 31.9 +/- 1.4 microM, respectively.     

超高效合相色谱法测定盐酸兰地洛尔中立体异构体的含量

建立了一种超高效合相色谱法( Ultra performance convergence chromatography,UPC2)分离和测定盐酸兰地洛尔中立体异构体的方法。本方法选用Daicel CHIRALPAK? IF手性色谱柱(150 mm ×4.6 mm,3μm),以CO2为流动相,甲醇-正丁醇-乙腈(1：1：1, V/V)+0.5％氨水为助溶剂,梯度洗脱,流速为2.8 mL/min,检测波长为223 nm。在建立的UPC2条件下,盐酸兰地洛尔的R,R-异构体、R,S-异构体和S,R-异构体的检出限分别为0.3、0.4和0.3 mg/L;线性范围分别为2~300 mg/L、5~300 mg/L和2~300 mg/L;加标回收率分别为103.4％,91.8％和101.7％;进样精密度分别为0.06％,0.09％和0.08％(n=6)。本方法能够满足盐酸兰地洛尔样品中3个立体异构体检查的相关要求。     

Bioassays guided fractionation of Coronopus didymus for its antifungal activity against Sclerotium rolfsii

Sclerotium rolfsii Sacc. is a pathogen of about 500 plant species. In a laboratory screening bioassay, methanolic extracts of 15?mg?mL?1 concentrations of different parts of Coronopus didymus (L.) Sm. (Brassicaceae) namely leaf, stem, inflorescence and root reduced the biomass of S. rolfsii by 67%, 26%, 40% and 58%, respectively. Methanolic root extract was successively fractionated with n-hexane, chloroform, ethyl acetate and n-butanol. All the concentrations (3.125-200?mg?mL?1) of ethyl acetate fraction completely inhibited the target fungal growth. Two compounds A and B were separated from this fraction by Thin Layer Chromatography (TLC). TLC fraction A was found highly effective against S. rolfsii with MIC value 15.62?μg?mL?1 as compared to MIC value 7.81?μg?mL?1 of the commercial fungicide mencozeb. This compound may be used for the synthesis of natural product based fungicide for the control of S. rolfsii.     

Separation and determination of aconitine alkaloids in traditional Chinese herbs by nonaqueous capillary electrophoresis

An easy, rapid, and simple nonaqueous capillary electrophoresis (NACE) method was developed for the identification and determination of three aconitine alkaloids, hypaconitine (HN), aconitine (AN), and mesaconitine (MN) within 6 min. The most suitable running buffer was composed of 60 mM ammonium acetate, 0.5% acetic acid, and 15% acetonitrile (ACN) in methanol with a fused-silica capillary column (50 cm x 75 microm ID). In the concentration range 12.5-1000 mg/L the calibration curves reveal linear relationships between the peak area for each analyte and its concentration (correlation coefficients: 0.9997 for HN, 0.9999 for AN, and 0.9995 for MN). The relative standard deviations of the migration time and peak area of the three alkaloids were 0.13, 0.57, 0.33 and 2.87, 1.06, 3.49%, respectively. The method was successfully applied to determine the three alkaloids in two commonly used traditional Chinese herbal medicines, the recoveries of the three constituents ranging between 94.7-101.9% for HN, 98.3-102.3% for AN, and 98.1-104.6% for MN.     

毛细管电泳-电致化学发光法分离测定麻黄中的麻黄碱、伪麻黄碱与甲基麻黄碱

以PB-Eu化学修饰电极为工作电极,对乙烯基苄基三乙基氯化铵离子液体为拆分添加剂,首次采用毛细管电泳-电致化学发光法对麻黄碱、伪麻黄碱和甲基麻黄碱进行了分离和检测。考察了检测电位、分离缓冲液的种类和酸度、添加剂用量等条件对电泳分离效果及检测灵敏度的影响。在优化条件下,3种混合药物可在8 min内达到基线分离,甲基麻黄碱、麻黄碱和伪麻黄碱的质量浓度分别在0.025～10、0.025～25、0.05～10 mg/L范围内与其峰面积呈良好但斜率略不同的两区段型线性关系,总的线性响应范围可达3个数量级。以质量浓度均为1.00 mg/L的3种混合药物合成样品进行6次平行测试,其峰面积和迁移时间的RSD分别小于4.5%和0.95%。该方法成功用于商品麻黄碱类药物制剂及中药麻黄原药中3种生物碱含量的测定,加标回收率为101%～111%。     

Biotransformation of isoflavones by the larvae of the common cutworm (Spodoptera litura)

Biotransformation of the 5,7,4'-trimethoxyisoflavone (1), 6,7,4'-trimethoxyisoflavone (2), and 7,4'-dimethoxyisoflavone (3) by insects, Spodoptera litura was investigated. Compound 1 was transformed to 5-hydroxy-7,4'-dimethoxyisoflavone (4), 7-hydroxy-5,4'-dimethoxyisoflavone (5) and 4'-hydroxy-5,7-dimethoxyisoflavone (6) by S. litura. Compounds 2 and 3 were hardly metabolized by S. litura. This suggested that compound 1 was converted to compounds 4, 5 and 6 by demethylation at the C-5, C-7 and C-4' position, respectively.     

Antioxidant,Antimicrobial, and Insecticidal Properties of a Chemically Characterized Essential Oil from the Leaves of Dittrichia viscosa L.

Since some synthetic insecticides cause damage to human health, compounds in plants can be viable alternatives to conventional synthetic pesticides. Dittrichia viscosa L. is a perennial Mediterranean plant known to possess biological activities, including insecticidal properties. The chemical composition of an essential oil (EOD) from D. viscosa, as well as its antioxidant, antimicrobial, and insecticidal effects on the cowpea weevil (Callosobruchus maculatus) were determined. Forty-one volatile compounds were identified in EOD, which accounted for 97.5% of its constituents. Bornyl acetate (41%) was a major compound, followed by borneol (9.3%), α-amorphene (6.6%), and caryophyllene oxide (5.7%). EOD exhibited significant antioxidant activity in all tests performed, with an IC₅₀ of 1.30 ± 0.05 mg/mL in the DPPH test and an EC₅₀ equal to 36.0 ± 2.5 mg/mL in the FRAP assay. In the phosphor-molybdenum test, EOD results ranged from 39.81 ± 0.7 to 192.1 ± 0.8 mg AAE/g E. EOD was active on E. coli (9.5 ± 0.5 mm), S. aureus (31.0 ± 1.5 mm), C. albicans (20.4 ± 0.5 mm), and S. cerevisiae (28.0 ± 1.0 mm), with MICs ranging from 0.1 mg/mL to 3.3 mg/mL. We found that 1 µL of EOD caused 97.5 ± 5.0% insect mortality after 96 h in the inhalation test and 60.0 ± 8.3% in the ingestion assay. The median lethal concentration (LC₅₀) was 7.8 ± 0.3 μL EO/L, while the effective concentration in the ingestion test (LC₅₀) was 15.0 ± 2.1 μL EO/L. We found that 20 µL of EOD caused a reduction of more than 91% of C. maculatus laid eggs.     

Alkaloids of Nitraria komarovii. N-Allylnitrarine and Komarovidine N-Oxide

Two new alkaloids, N-allylnitrarine and komarovidinine N-oxide were isolated from the aerial part ofNitraria komarovii.Their structures were established by chemical transformations and spectral data.     

n-(4,6-二取代嘧啶-2-基)-2-(2,4-二氯苯氧基)丙酰胺衍生物的合成及除草活性

二氯苯氧丙酸;嘧啶;酰胺;合成;除草活性