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Synthesis, Spectral and Electrochemical Studies of Complex of Uranium(IV) with Pyridine-3-Carboxylic Acid
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作者 Misbah Nazir Iftikhar Imam Naqvi 《American Journal of Analytical Chemistry》 2013年第3期134-140,共7页
The investigation of complexation of uranium with biological active ligands is vital for understanding uranium speciation in biosystems. A number of studies have been undertaken for investigating the complexation of u... The investigation of complexation of uranium with biological active ligands is vital for understanding uranium speciation in biosystems. A number of studies have been undertaken for investigating the complexation of uranium in its (VI) oxidation states but similar investigations pertaining to the interaction of uranium, in lower oxidation states, with biological ligands is scarce. The aim of the work is to bridge this gap and studies have been carried out to determine the coordination pattern of pyridine-3-carboxylic acid with uranium(IV). Semi-micro analysis, spectro-analytical techniques, magnetic susceptibility and cyclic voltammetry have been employed for the characterization of the synthesized complex. 展开更多
关键词 Uranium(IV) Pyridine-3-carboxylic acid Spectroscopic Techniques Magnetic Susceptibility Electrochemical Studies
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Synthesis of (2S,4S)-2-Substituted-3- (3-Sulfanylpropanoyl)-6- Oxohexahydropyrimidine-4-Carboxylic Acids as Potential Antihypertensive Drugs
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作者 Andrei Ershov Dmitry Nasledov +1 位作者 Igor Lagoda Valery Shamanin 《Journal of Materials Science and Chemical Engineering》 2015年第6期7-12,共6页
Proceeding from natural amino acid L-asparagine and commercially available aldehydes a stereoselective synthesis was developed of (2S,4S)-2-alkyl(aryl)-3-(3-sulfanylpropanoyl)-6-oxohexahy- dropyrimidine-4-carboxylic a... Proceeding from natural amino acid L-asparagine and commercially available aldehydes a stereoselective synthesis was developed of (2S,4S)-2-alkyl(aryl)-3-(3-sulfanylpropanoyl)-6-oxohexahy- dropyrimidine-4-carboxylic acids, potential antihypertensive drugs, inhibitors of the angiotensin converting enzyme. 展开更多
关键词 Synthesis of (2S 4S)-2-Substituted-3- (3-Sulfanylpropanoyl)-6- Oxohexahydropyrimidine-4-carboxylic acidS AS POTENTIAL ANTIHYPERTENSIVE DRUGS
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How Effective Is the Single-point Energy Calculation in Investigating the Reaction Mechanisms?New Decarboxylation Mechanism of Pyrrole-2-carboxylic Acid by Full Optimization with CPCM Solvation Model
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作者 程学礼 赵燕云 +3 位作者 何国芳 李丽清 韩银峰 吴仁涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第10期1449-1456,共8页
The decarboxylation of pyrrole-2-carboxylic acid in acid solutions was elucidated by full optimization with the CPCM solvation model at the B3LYP/6-31 l++G(d,p) level. Compared with the single-point energy calcula... The decarboxylation of pyrrole-2-carboxylic acid in acid solutions was elucidated by full optimization with the CPCM solvation model at the B3LYP/6-31 l++G(d,p) level. Compared with the single-point energy calculation, CPCM full optimization is better to model solvent environments to gain reasonable reaction mechanisms. The π interactions play a significant role in the decarboxylation of pyrrole-2-carboxylic acid (R). Firstly, the a hydrogen is protonated, but all of the carbonyl hydration pathways bear relatively higher energy barriers. The carbonyl group can rove over the pyrrole ring, but it does not lead to the speciation of pyrrole and protonated carbon dioxide for the latter is an energy-rich species. The decarboxylation mechanism proposed here is that, the protonated pyrrole-2-carboxylic acid (RH) decarboxylates via direct C-C bond cleavage with the aid of a water molecule to accommodate the proton on the carbonyl group. 展开更多
关键词 DECARBOXYLATION reaction mechanism pyrrole-2-carboxylic acid B3LYP
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Structure and Luminescent Property of a Novel 4-Hydroxyquinoline-2-carboxylate Based Zn(Ⅱ) Complex 被引量:4
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作者 盖艳丽 杨明 +3 位作者 冯蕊 陈莲 江飞龙 洪茂椿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第2期179-184,共6页
A 3D coordination polymer [Zn2(hqc)2(H2O)]n has been obtained from the reaction of 4-hydroxyquinoline-2-carboxylic acid (H2hqc) with zinc(II) salt under hydrothermal condition, and characterized by elemental a... A 3D coordination polymer [Zn2(hqc)2(H2O)]n has been obtained from the reaction of 4-hydroxyquinoline-2-carboxylic acid (H2hqc) with zinc(II) salt under hydrothermal condition, and characterized by elemental analysis, IR, TGA, PXRD and X-ray single-crystal diffraction. The complex crystallizes in the monoclinic system, space group P21/c with a = 14.305(2), b = 9.132(2), c = 15.356(2), β = 103.586(7)o, V = 1949.9(4)3, Z = 4, Dc = 1.782 g/cm3, μ = 2.508 mm-1, Mr = 523.06, F(000) = 1048, T = 293(2) K, λ(MoKα) = 0.71073, S = 1.008, the final R = 0.0329 and wR = 0.0745 for 3849 observed reflections (I 〉 2σ(I)). The title complex features a 3D framework via Zn(2) linking the 1D {Zn1(hqc)2}n chains. Thermogravimetric analysis shows that its framework is highly thermally stable up to 556 ℃ in the solid state. 展开更多
关键词 ZINC 4-hydroxyquinoline-2-carboxylic acid 3Dframework luminescence properties
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Synthesis of Stereoisomers of 3-Aminocyclohexanecarboxylic Acid and cis-3-Aminocyclohexene-5-carboxylic Acid 被引量:2
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作者 胡昱 余盛良 +2 位作者 杨玉金 朱槿 邓金根 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2006年第6期795-799,共5页
A practical synthesis of stereoisomers of 3-aminocyclohexanecarboxylic acid and cis-3-aminocyclohexene-5- carboxylic acid was achieved from cyclohexene-4-carboxylic acid via a key resolving approach with chiral 1-phen... A practical synthesis of stereoisomers of 3-aminocyclohexanecarboxylic acid and cis-3-aminocyclohexene-5- carboxylic acid was achieved from cyclohexene-4-carboxylic acid via a key resolving approach with chiral 1-phenylethylamine. 展开更多
关键词 RESOLUTION enantiopure γ-aminobutyric acid 3-aminocyclohexanecarboxylic acid 3-aminocyclohexene-5-carboxylic acid
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Arabidopsis Acetyl-Amido Synthetase GH3.5 Involvement in Camalexin Biosynthesis through Conjugation of Indole-3-Carboxylic Acid and Cysteine and Upregulation of Camalexin Biosynthesis Genes 被引量:2
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作者 Mu-Yang Wang Xue-Ting Liu +5 位作者 Ying Chen Xiao-Jing Xu Biao Yu Shu-Qun Zhang Qun Li Zu-Hua He 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2012年第7期471-485,共15页
Camalexin (3-thiazol-2'-yl-indole) is the major phytoalexin found in Arabidopsis thaliana. Several key intermediates and corresponding enzymes have been identified in camalexin biosynthesis through mutant screening... Camalexin (3-thiazol-2'-yl-indole) is the major phytoalexin found in Arabidopsis thaliana. Several key intermediates and corresponding enzymes have been identified in camalexin biosynthesis through mutant screening and biochemical experiments. Camalexin is formed when indole-3-acetonitrile (IAN) is catalyzed by the cytochrome P450 monooxygenase CYP71A13. Here, we demonstrate that the Ara- bidopsis GH3.5 protein, a multifunctional acetyl-amido synthetase, is involved in camalexin biosynthesis via conjugating indole-3-carboxylic acid (ICA) and cysteine (Cys) and regulating camalexin biosynthesis genes. Camalexin levels were increased in the activation-tagged mutant gh3.5-1D in both Col-0 and cyp71A13-2 mutant backgrounds after pathogen infection. The recombinant GH3.5 protein catalyzed the conjugation of ICA and Cys to form a possible intermediate indole-3-acyl-cysteinate (ICA(Cys)) in vitro. In support of the in vitro reaction, feeding with ICA and Cys increased camalexin levels in Col-0 and gh3.5-1D. Dihydrocamalexic acid (DHCA), the precursor of camalexin and the substrate for PAD3, was accumulated in gh3.5-1DIpad3-1, suggesting that ICA(Cys) could be an additional precursor of DHCA for camalexin biosynthesis. Furthermore, expression of the major camalexin biosynthesis genes CYP79B2, CYP71A12, CYP71A13 and PAD3 was strongly induced in gh3.5-1D. Our study suggests that GH3.5 is involved in camalexin biosynthesis through direct catalyzation of the formation of ICA(Cys), and upregulation of the major biosynthetic pathway genes. 展开更多
关键词 ARABIDOPSIS GH3.5 indole-3-carboxylic acid CYSTEINE camalexin biosynthesis
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Synthesis and Crystal Structure of a One-dimensional Infinite Chain Organotin Complex [(n-Bu)_3Sn(OCOC_5H_4NO)]_n 被引量:2
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作者 YIN Han-Dong GAO Zhong-Jun LI Gang XU Hao-Long HONG Min 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第11期1324-1327,共4页
A novel organotin complex [(n-Bu)3Sn(OCOC5H4NO)]n has been synthesized and characterized by elemental analysis, IR and ^1H NMR. The crystal structure has been determined by X-ray single-crystal diffraction. The cr... A novel organotin complex [(n-Bu)3Sn(OCOC5H4NO)]n has been synthesized and characterized by elemental analysis, IR and ^1H NMR. The crystal structure has been determined by X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P2 1/c with a = 8.982(2), b = 17.908(4), c = 13.219(3) A, β= 96.981(4)°, Z = 4, V= 2110.6(8) A^3, Dc = 1.347 g/cm^3, μ(MoKa) = 12.23 cm^-1, F(000) = 880, R = 0.0497 and wR = 0.1263. In the molecular structure of the title complex, the tin atoms are five-coordinated in a distorted trigonal bipyramidal geometry. A one-dimensional linear polymer is formed through an interaction between the O atoms of pyridine-3-carboxylic acid N-oxide and tin atoms of an adjacent molecule. 展开更多
关键词 organotin complex pyridine-3-carboxylic acid N-oxide synthesis crystal structure
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Pre-clinical evaluation of a new indirectly labeled 99mTc-6-hydrazinopyridine-3-carboxylic acid (HYNIC)-depreotide with HYNIC as bifunctional chelator 被引量:2
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作者 YU Fei LU Ming-li +8 位作者 ZHANG Xiao-ping FU Da HOU Min CAI Hai-dong LI Dan WANG Jian YUAN Xue-yu LU Zhong-wei DONG Feng 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第14期2538-2542,共5页
Background Technetium-99m or 99mTC is widely used for labeling peptide in nuclear medicine. Somatostatin and its analog can inhibit tumor cell growth after binding with its receptor. This research was to study the pre... Background Technetium-99m or 99mTC is widely used for labeling peptide in nuclear medicine. Somatostatin and its analog can inhibit tumor cell growth after binding with its receptor. This research was to study the preclinical effect of a new 99rnTc-6-hydrazinopyridine-3-carboxylic acid (HYNIC)-depreotide, indirect 99rnTc labeling of depreotide using HYNIC as a bifunctional chelator. Methods The cyclopeptide, cyclo-[(N-Me) Phe-Tyr-D-Trp-Lys-VaI-Hcy], the linear peptide, and [CICH2-CO.^-Dap-Lys- Cys-Lys-amide] were synthesized by Fmoc solid-phase synthesis. The cyclopeptide and the linear peptide were linked by liquid-phase synthesis. The product depreotide was isolated and purified by high performance liquid chromatography and was confirmed by mass spectrography. Depreotide was labeled with egmTc through a direct labeling method, using HYNIC as a bifunctional chelator. Paper chromatography method was used to calculate the labeling rate, and through the comparative analysis selected the best mark conditions. The new 99mTc-HYNIC-depreotide was tested by high-performance liquid chromatography (HPLC). The internalization and externalization rates of the new 99mTc-HYNIC-depreotide were studied in A549 cells. Furthermore, biodistribution of the radiopeptide was studied in nude mice, bearing tumors from human lung carcinoma cells SPC-A1. Results The molecular of synthesize depreotide was 1358, and the purity of it was 95.29%. The labeling efficiency of 99mTc-HYNIC-depreotide was highest at pH 6.0 and 15℃, about (70.95±0.84)%. The labeling rate of the new 99mTc-HYNIC-depreotide rose to a peak of (20.75±0.48)% at 60 minutes in A549 cells at 37℃ and decreased slightly later, while it elevated gradually during the time course at 4℃ and 25℃. The internalization rate of the new 99rnTc-HYNIC-depreotide at 37℃ increased gradually and reached the peak of 84.4% in 120 minutes, while the externalization rate of the new 99mTc-HYNIC-depreotide was always less than 20%. In mice bearing the experimental SPC-A1 tumor, the new 99mTc-HYNIC-depreotide demonstrated a high tumor uptake of (4.05±0.04)% ID/g at 1.5 hpi and remained high ((2.51±0.06)% ID/g) at 4 hpi. The tumor-to-lung activity concentration ratio (T/Lu) was very high for the new 99mTc-HYNIC-depreotide at all time points. So did the tumor-to-muscle activity (T/Mu) and tumor-to-blood activity concentration ratios (T/BI). Conclusion The findings suggested that the new 99mTc-HYNIC-depreotide might be a promising candidate radiopharmaceutical for imaging somatostatin receptor positive lung cancer. 展开更多
关键词 technetium-99m 6-hydrazinopyridine-3-carboxylic acid depreotide lung carcinoma
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Drug discovery based on the structure of FKBP12: Design, synthesis and evaluation of L-1,4-thiazane-3-carboxylic acid derivatives as neuroimmunophilin ligands
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作者 NIE AiHua XIAO JunHai +4 位作者 WANG LiLi LIAO GuoChao LIU HongYing REN Shen LI Song 《Science China Chemistry》 SCIE EI CAS 2007年第3期405-417,共13页
By choosing neuroimmunophilin FKBP12 as a therapeutical target, we have attempted to discover a new structural drug for treating neurodegenerative disease. This drug should possess neurotrophic activity and not affect... By choosing neuroimmunophilin FKBP12 as a therapeutical target, we have attempted to discover a new structural drug for treating neurodegenerative disease. This drug should possess neurotrophic activity and not affect the immune system. Based on the crystal structure of FKBP12, FK506 and Calcineurin complex, a series of small organic molecules were designed. These molecules were to have the ability of binding to FKBP12 in a virtual screening. By using a solution parallel synthetic method, these compounds were synthesized. The neuroprotective and neuroregenerative activities of these compounds were evaluated by binding assays, PC12 cells survival and neurite outgrowth model, chick dorsal root ganglion cultures (DRG) and 6-OHDA lesioned mice sympathetic nerve endings model. The evaluation results of these compounds showed that compound N308 has great promise as a candidate for a neuroprotective and neuroregenerative agent. 展开更多
关键词 FKBP12 L-1 4-thiazane-3-carboxylic acid derivatives DESIGN SYNTHESIS NEUROTROPHIC activity
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Synthesis,Characterization and Structure of Chiral Amino Acids and Their Corresponding Amino Alcohols with Camphoric Backbone
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作者 QIAN Hui-Fen HUANG Wei +1 位作者 LI Hui-Hui YAO Cheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第10期1243-1249,共7页
Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-(+)-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among t... Chiral amino acids and their corresponding amino alcohols bearing camphoric backbone were prepared from D-(+)-camphoric imide and characterized by infrared, elemental analysis, ESI-MS, and NMR measurements. Among them, one intermediate (1S,3R)-3-amino-2,2,3- trimethyl cyclopentane-1-carboxylic acid hydrochloride 3 was structurally elucidated by X-ray diffraction techniques. Versatile intermolecular hydrogen bonding interactions observed in its packing structure result in a two-dimensional framework. 展开更多
关键词 chiral amino acids and amino alcohols (1S 3R)-3-amino-2 2 3-trimethyl-cyclopentane-1-carboxylic acid hydrochloride hydrogen-bonding interactions crystal structures
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A Facile Synthesis of 9,10-Dimethoxybenzo[6,7]- ox-epino[3,4-<i>b</i>]quinolin-13(6<i>H</i>)-one and Its Derivatives
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作者 Dingqiao Yang Xiuli Liang +1 位作者 Xiongjun Zuo Yuhua Long 《International Journal of Organic Chemistry》 2013年第2期119-124,共6页
A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions o... A concise and efficient method for the synthesis of novel 9,10-imethoxybenzo[6,7]oxepino[3,4-b]quinolin13(6H)-one and its derivatives 7a-p has been developed via the intramolecular Friedel-Crafts acylation reactions of 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylic acids 6a-p with polyphosphoric acid (PPA) as catalyst and solvent under mild conditions. The key intermediates 6a-p were prepared through the in situ formation of ethyl 6,7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylates 5a-p followed by hydrolysis with aqueous ethanolic sodium hydroxide solution. The novel synthetic method has the advantages of good yields, easy work-up, and environmentally friendly character, which may provide a novel highly efficient process for making quinoline and related azaheterocycle libraries. 展开更多
关键词 The Intramolecular Friedel-Crafts Acylation Reaction: 9 10-Dimethoxybenzo [6 7]oxepino[3 4-b]quinolin-13(6H)-one and Its DERIVATIVES 6 7-Dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylic acid: Ethyl 7-dimethoxy-2-(phenoxymethyl)quinoline-3-carboxylate: PPA
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QSAR and Docking Studies of Thiazolidine-4-carboxylic Acid Derivatives as Neuraminidase Inhibitors 被引量:1
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作者 TONG Jian-Bo WANG Tian-Hao +1 位作者 WU Ying-Ji FENG Yi 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2020年第4期651-661,共11页
In order to understand the chemical-biological interactions governing their activities toward neuraminidase(NA),QSAR models of 28 thiazolidine-4-carboxylic acid derivatives with inhibitory influenza A virus were devel... In order to understand the chemical-biological interactions governing their activities toward neuraminidase(NA),QSAR models of 28 thiazolidine-4-carboxylic acid derivatives with inhibitory influenza A virus were developed.Here a quantitative structure activity relationship(QSAR)model was built by three-dimensional holographic atomic vector field(3D-HoVAIF)and multiple linear regression(MLR).The estimation stability and prediction ability of the model were strictly analyzed by both internal and external validations.The correlation coefficient(R2)of established MLR model was 0.984,and the cross-validated correlation coefficient(Q2)of MLR model was 0.947.Furthermore,the cross-validated correlation coefficient for the test set(Qext 2)was 0.967.The binding mode pattern of the compounds to the binding site of integrase enzyme was confirmed by docking studies.The results of present study indicated that this model can aid in designing more potent neuraminidase inhibitors. 展开更多
关键词 3D-QSAR thiazolidine-4-carboxylic acid derivatives 3D-HoVAIF molecular designing molecular docking
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Relationship between Coordination Structure and Biological Activity of Copper(II) Nicotinate 被引量:5
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作者 CHEN Qiang LI Qing-Lu 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第9期1141-1147,共7页
The copper(Ⅱ) complexes of pyridine-3-carboxylic acid (nicotinic acid) and pyridine-2-carboxylic acid (isonicotinic acid) were synthesized, and their structures were characterized by elemental analysis, infrare... The copper(Ⅱ) complexes of pyridine-3-carboxylic acid (nicotinic acid) and pyridine-2-carboxylic acid (isonicotinic acid) were synthesized, and their structures were characterized by elemental analysis, infrared spectrum, powder X-ray diffraction and so on. The results show that under experimental conditions, the ligands of synthesized copper nicotinate and copper isonicotinate are coordinated simultaneity with copper(Ⅱ) via the nitrogen of pyridine group and an oxygen of carboxylic acid group to form bidentate chelates. The crystal of copper nicotinate with two six-membered chelate rings belongs to monoclinic system, while that of copper isonicotinate having two five-membered chelate rings is of triclinic system. The tests show that the biological activities, such as the improvement of feed utilization, growth, anti-oxidation ability of organism and disease-resistant power, are different when copper nicotinate, copper inicotinate, copper-lysine chelate, copper-methionine chelate and copper sulphate are added in pig's feed, respectively. Due to its higher biological activity, less pollution and lower toxicity, copper nicotinate has wide potential applications as a feed additive. 展开更多
关键词 pyridine-3-carboxylic acid (copper nicotinate) copper pyridine-2-carboxylic acid (copper isonicotinate) copper coordination structure toxicity GROWTH-PROMOTING enzyme activity
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Indole Alkaloids from the Roots of Ervatamia hainanensis 被引量:4
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作者 Jian Peng HUANG Zi Ming FENG +2 位作者 Chong Fei ZHENG Pei Cheng ZHANG Yang Min MA 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期779-782,共4页
Two new indole alkaloids, named ibogamine-18-carboxylic acid, 3, 4-didehydro-7, 8-dioxo-methyl ester 1, ibogamine-18-carboxylic acid, 16, 17-didehydro-9, 17-dihydro-9-hydroxy (2-oxopropyl)-methyl ester 2, were isola... Two new indole alkaloids, named ibogamine-18-carboxylic acid, 3, 4-didehydro-7, 8-dioxo-methyl ester 1, ibogamine-18-carboxylic acid, 16, 17-didehydro-9, 17-dihydro-9-hydroxy (2-oxopropyl)-methyl ester 2, were isolated from Ervatamia hainanensis. Their structures were elucidated on the basis of spectroscopic methods. 展开更多
关键词 Ervatamia hainanensis indole alkaloid ibogamine-18-carboxylic acid 3 4-didehydro-7 8-dioxo-methyl ester ibogamine- 18-carboxylic acid 16 17-didehydro-9 17-dihydro-9-hydroxy-(2-oxopropyl)-methyl ester.
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Effect of Dietary Olaquindox on the Growth of Large Yellow Croaker(Pseudosciaena crocea R.) and the Distribution of Its Residues in Fish Tissues 被引量:3
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作者 LI Huitao WANG Weifang +3 位作者 MAI Kangsen AI Qinghui ZHANG Chunxiao ZHANG Lu 《Journal of Ocean University of China》 SCIE CAS 2014年第5期820-824,共5页
Olaquindox(OLA), one of quinoxaline-N, N-dioxides, has been put under ban. However it was used as a medicinal feed additive early; it promotes the growth of livestock and prevents them from dysentery and bacterial ent... Olaquindox(OLA), one of quinoxaline-N, N-dioxides, has been put under ban. However it was used as a medicinal feed additive early; it promotes the growth of livestock and prevents them from dysentery and bacterial enteritis. In this study, we evaluated the effect of dietary OLA on the growth of large yellow croaker(Pseudosciaena crocea R.) and the histological distribution of OLA and its metabolite 3-methyl-quinoxaline-2-carboxylic acid(MQCA) in fish tissues. Four diets containing 0(control), 42.5, 89.5 and 277.2 mg kg-1 OLA, respectively, were formulated and tested, 3 cages(1.0 m × 1.0 m × 1.5 m) each diet and 100 juveniles(9.75 ± 0.35 g) each cage. The fish were fed to satiation twice a day at 05:00 am and 17:00 pm for 8 weeks. The survival rate of fish fed the diet containing 42.5 and 89.5 mg kg-1 OLA was significantly higher than that of fish fed the diet containing 0 and 277.2 mg kg-1 OLA(P < 0.05), while the weight gain rate of fish fed the diet containing 42.5 and 89.5 mg kg-1 OLA was significantly higher than that of fish fed the diet without OLA(control)(P<0.05), but similar to that of fish fed the diet with 277.2 mg kg-1 OLA. Fish fed the diet with 277.2 mg kg-1 OLA had the highest content of OLA and MQCA in liver(3.44 and 0.39 mg kg-1, respectively), skin(0.46 and 0.09 mg kg-1, respectively) and muscle(0.24 and 0.06 mg kg-1, respectively). In average, fish fed the diet containing OLA had the highest content of OLA and MQCA in liver which was followed by skin and muscle(P < 0.05), whereas OLA and MQCA were not detectable in control. Our findings demonstrated that OLA and MQCA accumulated in large yellow croaker when it was fed with the diet containing OLA, thus imposing a potential safety risk to human health. 展开更多
关键词 large yellow croaker Pseudosciaena crocea OLAQUINDOX 3-methyl-quinoxaline-2-carboxylic acid
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Formation of Benzyl Oxazole, A Competitive Path with the Classical Bishler-Napieralski Reaction 被引量:1
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作者 Zhan Zhu LIU Ye Feng TANG Shi Zhi CHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期947-950,共4页
Several aromatic ring-substituted N-acetyl-phenylalanine methyl esters were treated with POCl3 in refluxing benzene, which is the typical condition of B-N reaction. It was found that the normal B-N product 3, 4-dihydr... Several aromatic ring-substituted N-acetyl-phenylalanine methyl esters were treated with POCl3 in refluxing benzene, which is the typical condition of B-N reaction. It was found that the normal B-N product 3, 4-dihydroisoquinoline-3-carboxylic acid methyl ester and/or 5-benzyl-2-methyl-4-methoxy oxazole could be obtained. The result depended mainly upon the electron-donating property of the substitutes on the benzene ring. Strong electron-donating groups located at para- or ortho- to the cyclization site will facilitate the formation of the normal B-N product 2. On the other hand, the absence or weak electron-donating groups tended to yield the oxazole product 3. It was established that the formation of benzyl oxazole is the competitive path with the B-N reaction. In this article, an explanation was given based on the mechanism of Bishler-Napieralski reaction. 展开更多
关键词 Bishler-Napieralski reaction benzyl oxazole 1 2 3 4-tetrahydroisoquinoline-3-carboxylic acid N-acetyl-phenytalanine methyl ester
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Synthesis,Structure,and Magnetic Property of One Snake-shaped Copper(Ⅱ)-organic Compound:Cu[Cu_2(PP)_2](CBPC)_2]·2(H_2O) 被引量:3
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作者 范黎明 李大成 +2 位作者 魏培海 张修堂 窦建民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第10期1381-1386,共6页
One novel copper(II)-organic compound,namely Cu[Cu2(PP)2](CBPC)2]·2(H2O)(1,H2CBPC = 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP = 3-(2-pyridyl)pyrazole),was designed... One novel copper(II)-organic compound,namely Cu[Cu2(PP)2](CBPC)2]·2(H2O)(1,H2CBPC = 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP = 3-(2-pyridyl)pyrazole),was designed and synthesized under hydrothermal conditions.X-ray diffraction analysis reveals that two Cu(II)ions in the quasi-planar dimmer of [Cu2(PP)2] are linked by the carboxylate oxygen atoms on the phenyl ring and the imidazole ring,respectively,yielding one snake-shaped structure.Magnetic measurements reveal that compound 1 shows the strongly antiferromagnetic property.Crystal data of 1:C58H52Cu3N10O10,Mr = 1239.72,monoclinic,P21/c,a = 14.900(7),b = 15.029(7),c = 12.308(6),β = 102.519(9)o,V = 2691(2)3,Z = 2,Dc = 1.530 g/cm3,F(000)= 1274,μ = 1.246 mm-1,R = 0.0416,wR = 0.0780(I 2σ(I))and S = 0.999. 展开更多
关键词 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid 3-(2-pyridyl)pyrazole) copper(II) magnetism TGA XPS
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Hydrothermal Synthesis and Crystal Structure of One Novel 1-D Copper(Ⅱ)-organic Framework:{[Cu_2(PP)_2(CBPC)]_2·7H_2O}_n 被引量:2
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作者 魏培海 吴小园 +5 位作者 范黎明 李大成 张修堂 窦建民 刘新征 石聪文 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第12期1774-1779,共6页
One novel 1-D copper(Ⅱ)-organic compound,namely {[Cu2(PP)2(CBPC)]2·7H2O}n(1,H2CBPC=1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP=3-(2-pyridyl)pyrazole),was synthesized ... One novel 1-D copper(Ⅱ)-organic compound,namely {[Cu2(PP)2(CBPC)]2·7H2O}n(1,H2CBPC=1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP=3-(2-pyridyl)pyrazole),was synthesized under hydrothermal conditions.X-ray diffraction analyses reveal that the two Cu(Ⅱ) ions in the distorted dimer [Cu2(PP)2] of 1 are linked by the carboxylate oxygen atoms on the phenyl and imidazole rings,respectively,forming one interesting snake-like chain.Single-crystal X-ray analyses reveal that it crystallizes in monoclinic,space group C2/c with a=30.656(8),b=12.715(3),c=22.405(5),β=122.758(3)°,V=7344(3)3,Z=4,Mr=1681.65,Dc=1.521 g/cm3,F(000)=3464,μ=1.221 mm-1,the final R=0.0453 and wR=0.1023 for 4617 observed reflections with Ⅰ 〉2σ(Ⅰ). 展开更多
关键词 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid 3-(2-pyridyl)pyrazole) copper(Ⅱ) TGA XPS crystal structures
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The Dependence of <i>N</i>-Malonyltryptophan Formation in Plants on Water Deficit (Review)
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作者 Kim Z. Gamburg 《Natural Science》 2021年第2期26-41,共16页
Drought stress in plants is accompanied by several metabolic changes. One of them is the appearance of <em>N</em>-malonyltryptophan (MT) during leaf wilting of many species, but there is a significant numb... Drought stress in plants is accompanied by several metabolic changes. One of them is the appearance of <em>N</em>-malonyltryptophan (MT) during leaf wilting of many species, but there is a significant number of plant species in which the appearance of MT did not occur. Plants of some species were able to synthesize also <em>N</em>-acetyltryptophan (AT). Excised tomato leaves incubated with D-amino acids (including D-Trp) transform them into malonyl- and acetyl-derivatives even without water deficit. However, MT which appeared during water deficit has been shown to contain L-Trp. Amino acid—1-amino-cyclopropane-1-carboxylic acid (ACC) is also malonylated during water deficit, but other L-amino acids were not malonylated. <em>N</em>-malonyl transferases specific for Trp and ACC have been found in several plants. The existence of <em>N</em>-malonyltransferase specific to L-Trp and appeared during water deficit in plants forming MT is supposed, but clear experimental proof has not been obtained yet. Plants can transform MT applied exogenously into Trp and further to indole-3-acetic acid (IAA). But no evidence has been appeared up to now that endogenous MT may be a source of IAA. It is unknown till now why it is necessary for plants of many species to malonylate only Trp during water deficit. How MT metabolized in animals and if it affects them is also unknown. The necessity to use molecular-genetic approaches for the elucidation of the physiological significance of MT formation during water deficit is underlined. 展开更多
关键词 Drought Stress N-Acetyltryptophan 1-Aminocyclopropane-1-carboxylic acid Indole-3-Acetic acid Tryptophan Malonylation
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壮药龙脷叶化学成分研究(Ⅱ) 被引量:8
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作者 韦建华 莫惠雯 +2 位作者 蒙秋艳 赵惠玲 卢汝梅 《中草药》 CAS CSCD 北大核心 2016年第20期3560-3564,共5页
目的研究壮药龙脷叶Sauropusrostratus的化学成分。方法通过硅胶、聚酰胺、MCI、凝胶等柱色谱及重结晶方法进行分离和纯化,根据理化性质和波谱数据对化合物结构进行鉴定。结果从龙脷叶75%乙醇提取物中分离得到19个化合物,分别鉴定为... 目的研究壮药龙脷叶Sauropusrostratus的化学成分。方法通过硅胶、聚酰胺、MCI、凝胶等柱色谱及重结晶方法进行分离和纯化,根据理化性质和波谱数据对化合物结构进行鉴定。结果从龙脷叶75%乙醇提取物中分离得到19个化合物,分别鉴定为正三十烷醇(1)、2,4-二叔丁基苯酚(2)、3-谷甾醇(3)、胡萝卜苷(4)、3,6.anhydro-2-deoxy-D-arabino-hexono-l,4-lactone(5)、烟酰胺(6)、东莨菪亭(7)、3β-hydroxy-26α,27β-arbor-13(18)-ene-24-carboxylicacid(8)、2R*,3R*,5S*-tnhydroxy-6R*-nonadecyltetrahydropyran-4-one(9)、大黄素(10)、原儿茶酸(11)、2,3-dideoxy-D-erythro-hex-2-enono-1,4-lactone(12)、咖啡酸(13)、3-乙酰氧基咖啡酸(14)、槲皮素(15)、D-半乳糖(16)、甘露醇(17)、橙黄胡椒酰胺(18)、山柰酚(19)。结论化合物8为新化合物,命名为龙劂叶酸;化合物2、5-14、16-18均为首次从该属植物中分离得到。 展开更多
关键词 龙脷叶 守宫木属 2 4-二叔丁基苯酚 3β-hydroxy-26α 27β-arbor-13(18)-ene-24-carboxylic acid 龙脷叶酸 橙黄胡 椒酰胺
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