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Impact of dietary fat levels and fatty acid composition on milk fat synthesis in sows at peak lactation
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作者 Li Zhe Uffe Krogh +3 位作者 Charlotte Lauridsen Mette Olaf Nielsen Zhengfeng Fang Peter Kappel Theil 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1134-1149,共16页
Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis... Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis,and milk fatty acid(FA)output is sparse in sows.This study aimed to evaluate impacts of dietary fat levels and FA composition on these traits in sows.Forty second-parity sows(Danish Landrace×Yorkshire)were assigned to 1 of 5 dietary treatments from d 108 of gestation until weaning(d 28 of lactation):low-fat control diet(3%added animal fat);or 1 of 4 high-fat diets with 8%added fat:coconut oil(CO),fish oil(FO),sunflower oil(SO),or 4%octanoic acid plus 4%FO(OFO).Three approaches were taken to estimate de novo milk fat synthesis from glucose and body fat.Results Daily intake of FA was lowest in low-fat sows within fat levels(P<0.01)and in OFO and FO sows within highfat diets(P<0.01).Daily milk outputs of fat,FA,energy,and FA-derived carbon reflected to a large extent the intake of those.On average,estimates for de novo fat synthesis were 82 or 194 g/d from glucose according to method 1 or 2 and 255 g de novo+mobilized FA/d according to method 3.The low-fat diet increased mammary FAS expression(P<0.05)and de novo fat synthesis(method 1;P=0.13)within fat levels.The OFO diet increased de novo fat synthesis(method 1;P<0.05)and numerically upregulated mammary FAS expression compared to the other high-fat diets.Across diets,a daily intake of 440 g digestible FA minimized milk fat originating from glucose and mobilized body fat.Conclusions Sows fed diets with low-fat or octanoic acid,through upregulating FAS expression,increased mammary de novo fat synthesis whereas the milk FA output remained low in sows fed the low-fat diet or high-fat OFO or FO diets,indicating that dietary FA intake,dietary fat level,and body fat mobilization in concert determine de novo fat synthesis,amount and profiles of FA in milk. 展开更多
关键词 Carbon metabolism De novo fat synthesis Dietary fatty acid Fat balance Mammary gene expression Mammary lipogenesis Milk fat production Piglet growth
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Study on the Total Synthesis of 3-Oxo-9β-Acetoxyilicic Acid─The Synthesis of 9β-Acetoxy-3(4),11(13)-Dien-5αH,7αH-12-Eudesmanoic Acid Methyl Ester
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作者 Jiong YANG Zbao Ming XIONG Yong Gang CREN and Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,ho University, Lanzhou 730000) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第12期0-0,共2页
The synthesis of 99-acetoxy-3(4), 11(13)-dien-5αH 7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone. The key step is the p-toluenesulfonhydrazide assisted reductiv rearrangement reaction
关键词 The synthesis of 9 H 7 H-12-Eudesmanoic acid Methyl Ester Dien-5 Study on the Total synthesis of 3-Oxo-9 Acetoxyilicic acid Acetoxy-3
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ASYMMETRIC SYNTHESIS Ⅻ:HIGHLY ENANTIOSELECTIVE SYNTHESIS OF α-AMINO ACIDS BY ALKYLATION OF THE KETIMINE FROM 2-HYDROXY-PINAN-3-ONE AND MENTHYL GLYCIN-ATE A DOUBLE ASYMMETRIC INDUCTION SYSTEM
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作者 Ai Qiao MI Zeng Xin MA Lan Jun WU Yao Zhong JIANG Chengdu Institute of Organic Chemistry,Academia Sinica,Chengdu 610015 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第2期115-118,共4页
A series of α-amino acids are obtained in 72-96% optical yields by alkylation of the ketimine derived from(+)-2-hydroxy-pinan-3-one and(-)-menthyl glycinate fol- lowed by hydrolysis of the alkylated intermediates wit... A series of α-amino acids are obtained in 72-96% optical yields by alkylation of the ketimine derived from(+)-2-hydroxy-pinan-3-one and(-)-menthyl glycinate fol- lowed by hydrolysis of the alkylated intermediates with mineral acid.The double asymmetric induction are explained by the transition model of lithium enolate. 展开更多
关键词 THF AMINO acidS BY ALKYLATION OF THE KETIMINE FROM 2-HYDROXY-PINAN-3-ONE AND MENTHYL GLYCIN-ATE A DOUBLE ASYMMETRIC INDUCTION SYSTEM ASYMMETRIC synthesis HIGHLY ENANTIOSELECTIVE synthesis OF ATE
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One-pot Synthesis of Lewis Acidic Ionic Liquids for Friedel-Crafts Alkylation 被引量:3
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作者 Ling HE Guo Hong TAO Wei Shan LIU Wei XIONG Tao WANG Yuan KOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第3期321-324,共4页
Novel Lewis acidic ionic liquids containing thionyl cations and chloroaluminate anions were obtained by one-pot synthesis for the first time. Their acidities were determined by acetonitrile probe on IR spectrography. ... Novel Lewis acidic ionic liquids containing thionyl cations and chloroaluminate anions were obtained by one-pot synthesis for the first time. Their acidities were determined by acetonitrile probe on IR spectrography. The ionic liquids were used as catalyst for Friedel-Crafts alkylation of benzene and 1-dodecene. The turnovers of l-dodecene were higher than 99%. Monoalkylbenzene selectivity was 98%, while the 2-substituent product selectivity was 45%. 展开更多
关键词 Ionic liquids green chemistry one-pot synthesis Lewis acidity alkylation.
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Hydrothermal Synthesis and Crystal Structure of Zinc(Ⅱ) Dinicotinate Complex [Zn(nic)_2(H_2O)_4](nic=nicotinic acid):A Three-dimensional Hydrogen-bond Network 被引量:2
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作者 MAOHong-yan ZHANGZong-pei +4 位作者 ZHANGHong-yun XUChen WANGEn-bo WUQing-an ZHUYu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第3期377-379,共3页
关键词 Nicotinic acid Zinc(Ⅱ) complex Crystal structure Hydrothermal synthesis
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Efficient one-pot synthesis of 14-substituted-14H-dibenzo[a,j]xanthenes using boric acid under solvent-free conditions 被引量:1
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作者 Zahed Karimi-Jaberi Mohsen Keshavarzi 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第5期547-549,共3页
Boric acid efficiently catalysed the one-pot reaction of alkyl or aryl aldehydes with 2-naphthol to afford the corresponding 14- alkyl-or aryl-14H-dibenzo[a,j]xanthenes in good yields under solvent-free conditions.
关键词 Boric acid 2-NAPHTHOL Dibenzoxanthenes Solvent-free synthesis
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A practical synthesis of trifluorophenyl R-amino acid:The key precursor for the new anti-diabetic drug sitagliptin 被引量:1
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作者 Li Li Zeng Ying Jie Ding +2 位作者 Gui Cheng Zhang Hong Rui Song Wen Hui Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1397-1399,共3页
Sitagliptin is the first new anti-diabetic drug in DPP-Ⅳ inhibitor class. The general synthesis of sitagliptin is by coupling of the β-amino acid fragment with the heterocycle fragment. Though the specific β-amino ... Sitagliptin is the first new anti-diabetic drug in DPP-Ⅳ inhibitor class. The general synthesis of sitagliptin is by coupling of the β-amino acid fragment with the heterocycle fragment. Though the specific β-amino acid can be easily made from the corresponding R-amino acid by Arndt-Eistert hornologation, the optically pure precursor R-amino acid is difficult to prepare. We herein reported a practical protocol to make the trifluorophenyl substituted R-amino acid 4 in 〉99.9% ee and 40.3% yield by the enzymatic resolution employing enantioselective hydrolysis and a general separation procedure. This protocol requires only cheap starting materials and friendly reaction condition. The procedure not only allows people to prepare the drug substance, but also provides an alternative method for prepareing the rare α-amino acid and the subsequent β-amino acid. 展开更多
关键词 SITAGLIPTIN β-Amino acid DPP-Ⅳ inhibitor Practical synthesis
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Microwave-induced synthesis and characterization of nanometer Ce_(0.5)Zr_(0.5)O_2 solid solution for the acidic catalytic reaction 被引量:1
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作者 HU Yucai YIN Ping LIANG Tao JIANG Wei DU Zhengkun CHEN Yonghua 《Rare Metals》 SCIE EI CAS CSCD 2008年第2期138-141,共4页
Ce0.5Zr0.5O2 solid solution was successfully synthesized using cerium nitrate, zirconium nitrate, and urea as raw materials by the microwave irradiation method and characterized by X-ray diffraction, fluorescence spec... Ce0.5Zr0.5O2 solid solution was successfully synthesized using cerium nitrate, zirconium nitrate, and urea as raw materials by the microwave irradiation method and characterized by X-ray diffraction, fluorescence spectrum, transmission electron microscopy, and infrared spectrum. Its acid catalytic activity was evaluated in the esterification reaction of acetic acid and n-butyl alcohol. The results show that Ce0.5Zr0.5O2 solid solution has cubic fluorite structure, and its particle diameter is in the nanometer scale. As a sort of solid acid, it possesses a higher acid catalytic activity and can be easily separated from reaction liquids. It can be used for several times, and basically, its activity keeps constant. The proton acid sites and Lewis acid sites exist in the structure of Ce0.5Zr0.5O2 solid solution. 展开更多
关键词 ceria-zirconia solid solution microwave-induced synthesis CHARACTERIZATION acidic catalytic reaction
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Molecular Cloning and Characterization of a Novel Gene Involved in Fatty Acid Synthesis in Brassica napus L. 被引量:1
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作者 XIAO Gang ZHANG Zhen-qian +4 位作者 LIU Rui-yang YIN Chang-fa WU Xian-meng TAN Tai-long GUAN Chun-yun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第6期962-970,共9页
Based on the sequence of a novel expressed sequence tag (EST), the full-length cDNA of 1 017 nucleotides was cloned from Brassica napus cv. Xiangyou 15 through rapid amplification of cDNA ends (RACE). The gene was... Based on the sequence of a novel expressed sequence tag (EST), the full-length cDNA of 1 017 nucleotides was cloned from Brassica napus cv. Xiangyou 15 through rapid amplification of cDNA ends (RACE). The gene was designated as Bnhol34 (HQ585980), encoding a protein of 338 amino acids. BLAST analysis showed no high degree of sequence identity to any known gene. The calculated molecular weight of the Bnhol34 protein was 36.23 kDa, and the theoretical isoelectric point was 8.74. The Bnhol34 was also cloned from a high oleic acid mutant 854-1 through homologous cloning. There was no difference between the two Bnhol34 genes. Bnhol34 was localized in a tissue-specific manner in B. napus, and its expression level was about eight-fold greater in Xiangyou 15 seeds than in 854-1. The promoter region sequences of Bnhol34 were then isolated from Xiangyou 15 and 854-1, and a 93-bp deletion was found to occur in the Bnhol34 promoter region of 854-1. Three abscisic acid-responsive cis-elements (ABRE) were identified in the promoter region of Xiangyou 15. Real-time PCR analyses revealed that exogenous abscisic acid increased Bnhol34 expression by about four-fold in Xiangyou 15 seeds, yet did not change Bnhol34 expression in 854-1. It appeared that Bnhol34 might be abscisic acid insensitive in 854-1. 展开更多
关键词 Brassca napus L. rapid amplification of cDNA ends high-efficient thermal asymmetric interlaced PCR fatty acid synthesis abscisic acid EXPRESSION
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Melt Synthesis and Characterization of Poly(L-lactic Acid) Chain Linked by Multifunctional Epoxy Compound 被引量:1
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作者 王远亮 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第5期774-779,共6页
High molecular weight(Mw) poly(L-lactic acid)s(PLLAs) were synthesized using multifunctional epoxy compound(Joncryl-ADR4370) as chain extender. The products were characterized by gel permeation chromatography... High molecular weight(Mw) poly(L-lactic acid)s(PLLAs) were synthesized using multifunctional epoxy compound(Joncryl-ADR4370) as chain extender. The products were characterized by gel permeation chromatography(GPC) and spectroscopy(1HNMR and FTIR). The results indicated that the Mw of PLLA increased with the increasing of the ratio of epoxy compound and the extending of reaction time. The highest Mw of PLLA reached 360 000 g/mol when the ratio of epoxy compound was 1.5 wt%. However, the reactants turned to cross-linking when the ratio of epoxy compound was over 1.5 wt%. Differential scanning calorimetry(DSC) measurements demonstrated that the glass transition(Tg) and melting temperatures(Tm) of products increased slightly as the increase of the molecular weight. Analysis of the hydrolytic degradation in vitro showed that the branched PLLA possessed the quicker degradability than that of the linear PLLA. 展开更多
关键词 melt synthesis poly(lactic acid epoxy compound chain extender
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Hydrothermal synthesis and structural studies of a new coordination polymer of lanthanum(Ⅲ) with benzene-1,2,4,5-tetracarboxylic acid and 4,4′-bipyridine 被引量:1
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作者 Masoumeh Tabatabaee Mahboubeh A. Sharif +1 位作者 Fatemeh Vakili Saina Saheli 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第3期357-362,共6页
A new lanthanum complex formulated as {(bpyH2)[La(btc)(H2O)4(NO3)]·2H2O}n (1) (btcH4=benzene-1,2,4,5-tetracarboxylic acid; bpy=4,4'-bipyridine) was hydrothermally synthesized. The complex was charact... A new lanthanum complex formulated as {(bpyH2)[La(btc)(H2O)4(NO3)]·2H2O}n (1) (btcH4=benzene-1,2,4,5-tetracarboxylic acid; bpy=4,4'-bipyridine) was hydrothermally synthesized. The complex was characterized by FT-IR spectroscopy, elemental analysis and X-ray diffraction. X-ray crystal structural analysis revealed that the compound belonged to the monoclinic space group C2/c with cell parameters a= 1.42806(7) nm, b=1.10258(5) nm, c=1.60333(8) nm and β=101.9400(10)°. The complex was polymeric with La^III atoms linked by four O atoms from two carboxylate groups of one benzene-1,2,4,5-tetracarboxylate. The LaIn atom was ten coordinated in a distorted tetracapped trigonal prism. In the crystal structure, a wide range of noncovalent interactions consisting of hydrogen bonding (of the types of O-H…O, N-H…O and C-H…O) and ion pairing interactions connected the various components into a supramolecular structure. 展开更多
关键词 lanthanum(III) complex hydrothermal synthesis coordination polymer hydrogen bonding benzene-1 2 4 5-tetracarboxylic acid rare earths
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Hydrothermal Synthesis, Crystal Structure and Thermal Analyses of Pyrazine-2,3-dicarboxylic Acid Bridged Co(II) Coordination Polymer of _∞~2[Co(phen)(μ-L)_(3/3)]·H_2O (H_2L = Pyrazine-2,3-dicarboxylic Acid) 被引量:3
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作者 ZHANGBi-Song 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第4期478-482,共5页
A novel pyrazine-2,3-dicarboxylic acid bridged Co(II) phen complex 2 ∞ [Co- ... A novel pyrazine-2,3-dicarboxylic acid bridged Co(II) phen complex 2 ∞ [Co- (phen)(μ-L)3/3]?H2O (H2L = pyrazine-2,3-dicarboxylic acid) has been hydrothermally synthesized, and X-ray single-crystal diffraction analysis shows that it crystallizes in the monoclinic system, space group P21/n with a = 11.480(2), b = 11.885(2), c = 12.939(3) ?, β = 110.55(3)°, V = 1653.1(6) ?3, Mr = 423.25, Dc = 0.425 g/cm3, Z = 4, R = 0.0361 and wR = 0.1011. The title complex consists of 2D 2 ∞ [Co(phen)(μ-L)3/3] layers and crystal water molecules. Each Co atom is octahedrally coordinated by three N atoms and three O atoms to form 2D 2 ∞ [Co(phen)(μ-L)3/3] polymeric layers. Furthermore, such 2D layers are stacked into 3D supramolecular frameworks via Van der Waals’ intermolecular forces, strong and weak hydrogen-bond interactions. The coordination phen and crystal water molecules are resided into cavities of the frameworks. 展开更多
关键词 Co(II) pyrazine-2 3-dicarboxylic acid 1 10-phenanthrline 2D coordination polymer hydrothermal synthesis crystal structure
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Solvothermal Synthesis, Crystal Structure and Luminescent Property of a Dy(Ⅲ) Coordination Polymer Constructed by 1,2,4,5-Benzenetetracarboxylic Acid 被引量:1
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作者 白威威 竺宁 +3 位作者 韩利民 洪海龙 高媛媛 索全伶 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第7期1021-1027,共7页
A three-dimensional coordination polymer {[Dy(H2btec)2/4(btec)3/6(H2O)]·2H2O} n has been synthesized through the reaction of DyCl3·6H2O and 1,2,4,5-benzenetetracarboxylic acid by solvothermal technique... A three-dimensional coordination polymer {[Dy(H2btec)2/4(btec)3/6(H2O)]·2H2O} n has been synthesized through the reaction of DyCl3·6H2O and 1,2,4,5-benzenetetracarboxylic acid by solvothermal technique, and the crystal structure was determined by X-ray diffraction. The Dy(Ⅲ) coordination polymer crystallizes in monoclinic, space group P21/n with a=10.7063(1), b=7.1491(1), c=17.1197(3), α=90, β=97.10, γ=90°, V=1300.31(3)3 , C10H9DyO11 , Dc=2.389g/cm3 , Z=4, F(000)=892, the final R=0.0165 and wR=0.0448 for I 〉 2σ(I). The title coordination polymer possesses a three-dimensional framework consisting of nine-coordinate Dy(Ⅲ) centers and two kinds of coordination modes for the 1,2,4,5-benzenetetracarboxylic acid ligands. Every btec4- ligand (deprotonated four protons from 1,2,4,5-benzenetetracarboxylic acid) in the title coordination polymer can clamp three Dy atoms like forceps, which could make the Dy atoms closer in the area of metal-metal interaction. The 3-D framework of the coordination polymer has many channels occupied by the free guest water molecules, and the hydrogen bonds between the coordinated carboxylic groups and guest water molecules could stabilize the crystal structure of the title coordination polymer. In addition, the luminescence properties were also studied. 展开更多
关键词 solvothermal synthesis 1 2 4 5-benzenetracarboxylic acid coordination polymer Dy^3+
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REDUCTION BY HYPOPHOSPHOROUS ACID IN ORGANIC SYNTHESIS 被引量:1
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作者 Xue WANG Ye Di GUAN 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第5期407-408,共2页
Hypophosphorous acid and its salt were found to serve as a new agent for selective reduction of α,β-unsaturated carbonyl compounds under mild reaction conditions.
关键词 ETOH HO acid REDUCTION BY HYPOPHOSPHOROUS acid IN ORGANIC synthesis
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A METHOD OF SYNTHESIS OF PHENYL-LACTIC ACID AND SUBSTITUTED PHENYL LACTIC ACIDS 被引量:1
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作者 Jian Ming YU Fen XUE Dept.of Organic Chemistry,Shanghai Medical University.Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第8期673-674,共2页
A method for the conversion of α-acetamido-β-substituted phenyl acrylic acid (αtβSPAA)into substituted phenyl lactic acid(SPLA)is described and an improved Clemmensen reduction reagent is used.
关键词 HCI acid A METHOD OF synthesis OF PHENYL-LACTIC acid AND SUBSTITUTED PHENYL LACTIC acidS
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A SYNTHESIS OF TETRAMETHYL ETHER OFROSMARINIC ACID BENZYL ESTER 被引量:1
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作者 Yan ZHUANG Zong Ru GUO +1 位作者 Guang Zhong YANG Xiao Tian LIANG(Institute of Materia Medial Chinese Academy of Medical SciencesPeking Union Medical College, Xian Nong Tan Street,Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第6期507-508,共2页
A rosmarinic acid derivative, tetramethyl ether of rosmarinic acid benzyl ester, was synthesized. This is the first report of building this structural skeleton.
关键词 acid A synthesis OF TETRAMETHYL ETHER OFROSMARINIC acid BENZYL ESTER
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The Synthesis of Hexamethyl Ether of Salvianolic Acid A Benzyl Ester 被引量:2
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作者 Yan ZHUANG Zong Ru GUO +1 位作者 Guang Zhong YANG Xiao Tian LIANG(Institute of Materia Medica.Chinese Academy of Medical Sciences Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第10期888-891,共4页
A salvianolic acid A derivative, hexamethyl ether of salvianolic acid A benzyl ester, was synthesized in fourteen steps. The overall yield was 3.4 parts per thousand. The compound was identified by (1)HNMR and MS. Thi... A salvianolic acid A derivative, hexamethyl ether of salvianolic acid A benzyl ester, was synthesized in fourteen steps. The overall yield was 3.4 parts per thousand. The compound was identified by (1)HNMR and MS. This is the first report of building this structural skeleton. 展开更多
关键词 The synthesis of Hexamethyl Ether of Salvianolic acid A Benzyl Ester
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Solvothermal Synthesis,Crystal Structure and Photoluminescence Property of a 3D Lead(Ⅱ)Coordination Polymer Based on Terephthalic Acid 被引量:1
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作者 林小英 杨攀 +2 位作者 陈君 刘明华 林诚 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第1期61-68,共8页
Solvothermal reaction of Pb(NO3)2·6H2O with rigid linear ligand terephthalic acid(H2pta) in N,N-dimethylformamide(DMF) produced a new three-dimensional(3D) lead(Ⅱ)coordination polymer[Pb2(pta)1.5(μ... Solvothermal reaction of Pb(NO3)2·6H2O with rigid linear ligand terephthalic acid(H2pta) in N,N-dimethylformamide(DMF) produced a new three-dimensional(3D) lead(Ⅱ)coordination polymer[Pb2(pta)1.5(μ4-OH)(DMF)]n 1,and its structure was characterized by single-crystal X-ray diffraction analyses.In polymer 1,the μ4-OH bridges the nearby lead(Ⅱ) ions into an infinite one-dimensional(1D) chain,and then the organic ligand pta^2- joins the neighbored chains into a 3D structure by two similar connection modes in different configurations.The solid-state photoluminescent studies revealed that 1 exhibits a strong greenish emission mainly originating from ligand-to-metal charge transfer between the delocalized π bonds of the aromatic carboxylate ligand pta^2- and the p orbitals of the Pb^2+ centers. 展开更多
关键词 solvothermal synthesis lead(Ⅱ) coordination polymer terephthalic acid photoluminescence property crystal structure
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A facile electrochemical synthesis of caffeic acid derivatives in the presence of acetylacetone or methyl acetoacetate in aqueous medium
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作者 Cheng Chu Zeng Li Ming Hu +1 位作者 Jia Zeng Ru Gang Zhong 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第2期130-132,共3页
关键词 Caffeic acid Electrochemical synthesis ACETYLACETONE Methyl acetoacetate
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Effect Factors in Synthesis of Nicotinic Acid by Electrooxidation of 3-Picoline
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作者 SUN Xiu-yun ZHANG Yu-min +3 位作者 CAO Xue-jing ZHANG Heng-bin LI Fei XU Yu-ling 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第6期692-696,共5页
In an electrolytic cell with a proton exchange membrane, nicotinic acid was synthesized at the PbO2 anode. The relationship between the current density and the potential at different concentrations of 3-picoline and s... In an electrolytic cell with a proton exchange membrane, nicotinic acid was synthesized at the PbO2 anode. The relationship between the current density and the potential at different concentrations of 3-picoline and sulfuric acid as well as at different temperatures was studied with polarization curves. The effects of the concentrations of sulfuric acid and 3-picoline, the anode potential and the reaction temperature on the selectivity and the current efficiency were explored. The optimum conditions were determined by orthogonal experiments. Under optimum conditions the selectivity and the current efficiency for the synthesis of nicotinic acid might reach 89% and 65%, respectively. The, concentrations of 3-picoline and nicotinic acid were analyzed with high performance liquid chromatography and the product was characterized with elemental analysis, chromatography-mass spectrometry and IR spectrometry. 展开更多
关键词 3-PICOLINE Nicotinic acid ELECTROOXIDATION Electroorganic synthesis
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