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cis,trans-4-戊基环己基甲酸的合成及异构体转位 被引量:1
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作者 张越 牛玉环 +2 位作者 王荣耕 吴鹏程 马东来 《河北工业科技》 CAS 2006年第1期24-26,共3页
采用Ni5249P为催化剂,在水相碱性条件下,反应温度为175℃,反应压力为9MPa,加氢合成4-戊基环己基甲酸[m(civ):m(trans-)=75:253。在200-220℃进行异构体转位,可以使4-戊基环己基甲酸产物中m(cir):m(trans-)=2:98,trans... 采用Ni5249P为催化剂,在水相碱性条件下,反应温度为175℃,反应压力为9MPa,加氢合成4-戊基环己基甲酸[m(civ):m(trans-)=75:253。在200-220℃进行异构体转位,可以使4-戊基环己基甲酸产物中m(cir):m(trans-)=2:98,trans-4-戊基环己基甲酸收率为95%。 展开更多
关键词 cis trans-4-戊基环己基甲酸 trans-4-戊基环己基甲酸 异构化
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4-(trans-4”’-n-烷基环己烷甲氧基)-4'-氰基联苯的合成
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作者 李瑞军 左秀锦 《大连大学学报》 1999年第4期53-55,共3页
从trans-4-n-烷基环己基甲醇和4-溴-4’-羟基联苯出发经磺酸酯化、醚化、氰代合成了三种4-(trans-4”-n-烷基环己烷甲氧基)-4’-氰基联苯液晶化合物,经IR、MS、元素分析确证了化学结构.
关键词 4-(trans-4″-n-烷基环己烷甲氧基)-4′-氰基联苯 差示扫描量热仪 粘度 液晶显示器
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Synthesis and Crystal Structure of Trans-4-[(5-(2,4-Dichlorophenoxy)-3-methyl-1-phenyl-1H-pyrazol-4-yl)methyleneamino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 被引量:4
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作者 孙凤梅 田孟魁 +1 位作者 杨靖华 连照勋 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第7期789-792,共4页
The title compound trans-4-[(5-(2,4-dichlorophenoxy)-3-methyl- 1-phenyl-1H-pyrazol-4-yl)methyleneamino]- 1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 (C28H23Cl2N5O2, Mr = 532.41) has been synthesized and its... The title compound trans-4-[(5-(2,4-dichlorophenoxy)-3-methyl- 1-phenyl-1H-pyrazol-4-yl)methyleneamino]- 1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one 3 (C28H23Cl2N5O2, Mr = 532.41) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1- with a = 8.9438(4), b = 11.6065(5), c = 14.2215(6)A, α = 112.566(1), β = 92.324(2), γ = 102.91(1)°, V= 1315.65(10) A^3, Z = 2, Dc = 1.344 g/cm^3,μ(MoKa) = 0.282 mm^-1, λ = 0.71073 A, F(000) = 552, the final R = 0.0587 and wR = 0.1578 for 5071 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the product is a thermodynamically stable trans isomer. Intra- and intermolecular C( 12)-H(12)…O(1) and C(28)-H(28)...O(1)# 1 hydrogen bonds were observed in the title compound. 展开更多
关键词 trans-4-[ 5-(2 4-dichlorophenoxy)-3-methyl- 1-phenyl- 1H-pyrazol-4-yl)methylene amino]-1 5-dimethyl-2-phenyl-1 2-dihydropyrazol-3-one synthesis crystal structure
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Determination of trans-4-hydroxy-2-alkenals in thermally treated soybean oil by SPE-HPLC 被引量:1
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作者 Hongying Hua Shimin Wu Xin Ma 《Grain & Oil Science and Technology》 2022年第3期107-113,共7页
Trans-4-hydroxy-2-hexenal(4-HHE) and trans-4-hydroxy-2-nonenal(4-HNE) are secondary lipid peroxidation products in edible oils, which are cytotoxic and genotoxic. They could covalently bind with protein, phospholipids... Trans-4-hydroxy-2-hexenal(4-HHE) and trans-4-hydroxy-2-nonenal(4-HNE) are secondary lipid peroxidation products in edible oils, which are cytotoxic and genotoxic. They could covalently bind with protein, phospholipids and DNA, further disrupting the normal function of liver, lung and brain.Derivation process was generally conducted during pretreatment before detection and quantification of 4-HHE and 4-HNE. However, the derivation procedures were time consuming and chemical degradation may occur during the process. Hence, this paper aims to establish a simple solid phase extractionhigh performance liquid chromatography(SPE-HPLC) method to determine the 4-HHE and 4-HNE contents in thermally treated soybean oil. C18 solid phase extraction was applied in the pretreatment process. Firstly, the reliability of the method was evaluated. Good linearity was observed in the range of 0.1–0.5 μg/m L and 0.5–10 μg/m L for 4-HHE and 4-HNE. The limit of detection(LOD) of 4-HHE and 4-HNE were 0.0486 and 0.0129 μg/m L, respectively. And the limit of quantitation(LOQ) of4-HHE and 4-HNE were 0.1458 and 0.0431 μg/m L, respectively. Recovery rate were in the range of89.11%–91.58% and 71.83%–79.40% for 4-HHE and 4-HNE, respectively. The method achieved the extraction, purification and detection of 4-HHE and 4-HNE simultaneously and had the advantages of simple operation, effectiveness, high precision, good repeatability. Then, the method was applied to monitor the concentrations of 4-HHE and 4-HNE in soybean oil heated at 180 °C for 40 h. The contents of 4-HHE and 4-HNE were 0–0.32 μg/g and 0–6.97 μg/g, respectively, which provided guidance for evaluating health risks of thermally treated soybean oil during heating. 展开更多
关键词 trans-4-hydroxy-2-hexenal trans-4-hydroxy-2-nonenal Soybean oil
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Facile synthesis of 9-(N-amino-4-fluoromethyl-3-pyrrolidinyl)-2-fluoro-6-aminopurine from trans-4-hydroxy-L-proline
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作者 Ye Qing Li Ming Lu Chun Xu Lu Sai Jian Zhu Qi Fa Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第11期1313-1315,共3页
A novel and simple procedure for synthesis of azanucleoside by Mitsunobu reaction between N-(p-nitrobenzyloxycarbonyl)- trans-4-hydroxy-D-proline methyl ester obtained from trans-4-hydroxy-L-proline after six-step r... A novel and simple procedure for synthesis of azanucleoside by Mitsunobu reaction between N-(p-nitrobenzyloxycarbonyl)- trans-4-hydroxy-D-proline methyl ester obtained from trans-4-hydroxy-L-proline after six-step reaction and 2-fluoro-6-azidopurine is described, and azanucleoside is fluorinated by new fluridizer 2,2-difluoro-1,3-dimethylimidazolidine (DFI). All reactions could be carried out under mild condition. 展开更多
关键词 trans-4-Hydroxy-D-proline 2-Fluoro-6-azidopurine Fluoride azanucleosides Mitsunobu reaction DFI
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Synthesis and Structural Characterization of a Ni(Ⅱ) Complex [Ni(H_2O)_4(4,4'-bipy)_2](hca)_2 被引量:2
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作者 ZHOU Qiu-Xuan XU Qing-Feng +1 位作者 LU Jian-Mei XIA Xue-Wei 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第11期1392-1396,共5页
The reaction of Ni(CH3COO)2.6H2O, 4-hydroxycinnamic acid (Hhca) and 4,4'-bipyridine (bipy) ligand in water-solution afforded a mononuclear complex [Ni(H2O)4(4,4'-bipy)2](hca)2 which was characterized by ... The reaction of Ni(CH3COO)2.6H2O, 4-hydroxycinnamic acid (Hhca) and 4,4'-bipyridine (bipy) ligand in water-solution afforded a mononuclear complex [Ni(H2O)4(4,4'-bipy)2](hca)2 which was characterized by IR, elemental analysis, TGA and single-crystal X-ray diffraction. X-ray crystallography analysis reveals that the complex is of triclinic, space group PI with a = 7.0238(14), b = 7.2934(11), c = 17.186(4) A, α = 87.073(13), β = 84.354(10), γ = 81.961(12)°, V= 866.9(3) A^3, Z = 1, Dc = 1.474 g/cm^3, F(000) = 402,μ = 62.7 mm^-1, R = 0.0411, wR = 0.0862 and GOF = 1.048. In solid state, the cation [Ni(H2O)4(4,4'-bpy)2]^2+ connects six nearby hca counter anions via O-H…O hydrogen bonds to form an extended 2D lattice framework and the O-…N hydrogen bonds finally link the 2D layers into an infinite 3D network. 展开更多
关键词 nickel(Ⅱ) 4 4'-bipyridyl trans-4-hydroxycinnamic acid crystal structure
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皂角刺中黄酮类化学成分的分离鉴定 被引量:21
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作者 李万华 李琴 +1 位作者 王小刚 赵文明 《西北大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第6期763-765,770,共4页
目的研究中药材皂角刺中黄酮类化合物化学成分。方法用溶剂萃取、反复柱层析方法,分离纯化皂角刺中黄酮类化合物,通过NMR,MS等波谱技术确定其化学结构,并进行细胞模型的体外活性筛选。结果从皂角刺中分离得到两种黄酮类化合物,结构鉴定... 目的研究中药材皂角刺中黄酮类化合物化学成分。方法用溶剂萃取、反复柱层析方法,分离纯化皂角刺中黄酮类化合物,通过NMR,MS等波谱技术确定其化学结构,并进行细胞模型的体外活性筛选。结果从皂角刺中分离得到两种黄酮类化合物,结构鉴定为(+)trans-2R,3R-3′,4′,5,7-tetrahydroxyflavanonol(1)和8-C-glucopyranosyl-3,4′,7-trihydroxyflavone(2),化合物2显示出明显的组织蛋白酶B抑制活性(CAT-B模型)。结论该两种化合物均为首次从皂角刺中分离得到的单体黄酮类化合物,且发现化合物2具有组织蛋白酶B抑制活性。 展开更多
关键词 皂角刺 (+)trans-2R 3R-3’ 4 5 7-tetrahydroxyflavanonol 8-C—glucopyranosyl-3 4 7-trihydroxyflavone
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Stress-induced Solid-Solid Crystal Transition in Trans-1,4-polyisoprene 被引量:2
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作者 Chun-Bo Zhang Lei Wang +3 位作者 Bo Yang Hui Zhao Guo-Ming Liu Du-Jin Wang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2022年第3期256-265,I0006,共11页
The polymorphic transition of trans-1,4-polyisoprene(TPI) during stretching was investigated by in situ wide-angle X-ray diffraction and Fourier transform infrared spectroscopy. The influences of the initial structure... The polymorphic transition of trans-1,4-polyisoprene(TPI) during stretching was investigated by in situ wide-angle X-ray diffraction and Fourier transform infrared spectroscopy. The influences of the initial structure, stretching temperature, and strain rate on the contents of different crystal modifications(α, β) were explored. The results confirm that the α-β transition occurs during stretching of TPI that only contains αcrystal(α-TPI). When the stress is relaxed, the β crystal formed during stretching remains, which indicates that the transition is irreversible. On the other hand, stretching of TPI that only contains β crystal(β-TPI) results in orientated β crystal. No β-α transition occurs during stretching. The different structures of stretched α-TPI and β-TPI exclude the previously proposed "melting-recrystallization mechanism". The α-β transition depends significantly on temperature and strain rate, indicating the transition is governed both by thermodynamics and kinetics. Our results support a solid-solid transition mechanism rather than a melting-recrystallization mechanism. The irreversible nature of the transition is attributed to the metastability of the β phase in the unstretched state. Different from the "β phases" that appear in polymers with stress-induced reversible transitions, e.g. poly(butylene terephthalate) and poly(butylene succinate), the stability of β phase in TPI is high that can be long-lived.The strain rate dependence of α-β transition hinders the determination of critical stress for the transition. It further indicates that the local stress within the sample is more heterogeneous at higher strain rates. 展开更多
关键词 trans-1 4-polyisoprene Crystal transition DEFORMATION CRYSTALLIZATION
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Synthesis of New Multibranch Chromophores with Strong Light-emitting in Solution and in PMMA Film 被引量:1
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作者 XiaoMeiWANG TianSheYANG +3 位作者 PingYANG QinFenSHI WanLiJANG HongDeXIE 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第11期1135-1138,共4页
Three new chromophores with triphenylamine as molecular focal point bearing one, two, or three 4-(n-butyloxystyryl) group(s) at the periphery respectively, (named as T1, T2, and T3) have been synthesized and character... Three new chromophores with triphenylamine as molecular focal point bearing one, two, or three 4-(n-butyloxystyryl) group(s) at the periphery respectively, (named as T1, T2, and T3) have been synthesized and characterized. It is interesting to find that the fluorescence quantum yield increases from T1 (0.489), to T3 (0.535), and to T2 (0.628) in cyclohexane, meanwhile the lifetime for T3 is shorter than T1 and T2, which is an important characteristic for applications in light emitting diode. Also PMMA (polymethyl methacrylate) film doped with T3 gives stronger fluorescence than T1, and T2. Cyclic voltammetry showed that T3 exhibited lowest oxidation potential of 0.52 V vs SCE, suggesting its better hole-transport property. 展开更多
关键词 trans-4-(4'-n-butyloxy-styryl) triphenylamine trans-4 4- di (4'-n- butyloxy- styryl)- triphenylamine trans-4 4 4-tris(4'-n-butyloxystyryl)triphenylamine photo- luminescence film.
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Fabrication of Trans-1,4-polyisoprene Nanofibers by Electrospinning and Its Crystallization Behavior and Mechanism
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作者 hua-feng shao zhi-lu li +2 位作者 贺爱华 chen-guang liu wei yao 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2016年第7期797-804,共8页
Trans-1,4-polyisoprene(TPI) nanofibers have been fabricated successfully through electrospinning technology.Through the control of electrospinning parameters, highly crystallized TPI fresh fibers composed mainly of ... Trans-1,4-polyisoprene(TPI) nanofibers have been fabricated successfully through electrospinning technology.Through the control of electrospinning parameters, highly crystallized TPI fresh fibers composed mainly of β phase were produced. Morphology and diameter of TPI nanofibers can be controlled by adjusting the electrospinning conditions. The in situ observations of FTIR spectra revealed that the crystallinity of the TPI fibers decreased with aging. While for TPI nanofibers aging at 45 °C for 24 h, a decrease in crystallinity as well as β to a transformation was observed with aging and these changings happened in the first 50 h during aging. The mechanism for β-TPI formation during electrospinning process and the reduced crystallinity with aging were proposed. 展开更多
关键词 ELECTROSPINNING trans-1 4-polyisoprene CRYSTALLIZATION TRANSFORMATION βphase
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Low and Wide Phase Transition Temperature Dimesogenic Compounds Consisting of a Cholesteryl and 4-(trans-4-n-Alkylcyclohexyl)phenoxy Mesogens
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作者 张春波 丛志奇 +2 位作者 尹炳柱 田英载 久保勘二 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2006年第3期435-438,共4页
Unsymmetrical dimesogenic compounds with cholesteryl and 4-(trans-4-n-alkylcyclohexyl)phenoxy parts were synthesized by condensation of cholester-3-yl 6-bromohexanoate with appropriate 4-(trans-4-n-alkylcyclohexyl... Unsymmetrical dimesogenic compounds with cholesteryl and 4-(trans-4-n-alkylcyclohexyl)phenoxy parts were synthesized by condensation of cholester-3-yl 6-bromohexanoate with appropriate 4-(trans-4-n-alkylcyclohexyl)- phenols. Structures and thermal phase behaviour of these dimesogenic compounds have been confirmed by IR, IH NMR, elemental analysis, DSC, polarity microscopy and XRD measurements. Their thermal phase behaviour was significantly different with that of other cholesterol-based dimesogens while they exhibited low and wide phase transition temperature. 展开更多
关键词 liquid crystal dimesogen cholesteryl 4-(trans-4-n-alkylcyclohexyl)phenol chiral nematic phase
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Synthesis of both epimeric triacid ananlogs of kainic acid
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作者 Hai Ling Hao Pi Sun +2 位作者 Guang Xing Wang Kyoji Fruta Masaaki Suzuki 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第3期269-272,共4页
A practical and cheap method for synthesis of C-4 carboxylic acid substituted kainic acid analogue 5 and its epimer 6 from trans-4-hydroxyproline is described. Using this method, more interesting intermediates and ana... A practical and cheap method for synthesis of C-4 carboxylic acid substituted kainic acid analogue 5 and its epimer 6 from trans-4-hydroxyproline is described. Using this method, more interesting intermediates and analogues could be obtained easily. 展开更多
关键词 trans-4-hydroxyprolime Kainic acid analogue Practical synthesis
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Solid state transformation of <i>cis</i>and <i>trans</i>methylcyclopentadienyl molybdenumdicarbonyltriphenylphosphineiodide on pelleting utilizing different diluents
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作者 Olalere G. Adeyemi Umaru Salami 《Open Journal of Inorganic Chemistry》 2012年第2期28-32,共5页
[(η5-C5H4Me)Mo(CO)2PPh3I] undergoes solid state transformation on the formation of a good pellet for FT IR measurement. There was a formation of the products mixture on pelleting using different diluents of group I m... [(η5-C5H4Me)Mo(CO)2PPh3I] undergoes solid state transformation on the formation of a good pellet for FT IR measurement. There was a formation of the products mixture on pelleting using different diluents of group I metal salts on either the cis or the trans isomer of the [(η5-C5H4Me)Mo(CO)2PPh3I] complex. The cis or the trans isomer gave the same IR spectra i.e. a mixture of cis and trans isomer of the complex. It does not matter the isomer started with in the course of solid state transformation reaction, an equilibrium ratio of 30/70 (trans/cis) will still be achieved. The solid state IR spectra show very strong peaks at νco 1957, 1947 and strong peaks at 1867, 1853 cm–1. The individual IR cis/trans isomer will therefore show at 1947 and 1853/1957 and 1867 cm–1. The solution IR spectra gave, cis = 1961, 1875 and trans = 1963, 1882 cm–1 in dry CHCl3. Hence, most of the solid state IR measurement of the organometallic complex of the type (η5-C5H4Me)Mo(CO)2(PPh3)I on pelleting will give isomer mixture. 展开更多
关键词 Solid State cis/trans-[(η5-C5H4Me)Mo(CO)2PPh3I] PELLETING DILUENTS FT IR
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Synthesis and anti-HIV activities of phorbol derivatives
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作者 HUANG Xiaolei TANG Chengrun +9 位作者 HUANG Xusheng YANG Yun LI Qirun MA Mengdi ZHAO Lei YANG Liumeng CUI Yadong ZHANG Zhenqing ZHENG Yongtang ZHANG Jian 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2024年第2期146-160,共15页
In this study,37 derivatives of phorbol esters were synthesized and their anti-HIV-1 activities evaluated,building upon our previous synthesis of 51 phorbol derivatives.12-Para-electron-acceptor-trans-cinnamoyl-13-dec... In this study,37 derivatives of phorbol esters were synthesized and their anti-HIV-1 activities evaluated,building upon our previous synthesis of 51 phorbol derivatives.12-Para-electron-acceptor-trans-cinnamoyl-13-decanoyl phorbol derivatives stood out,demonstrating remarkable anti-HIV-1 activities and inhibitory effects on syncytia formation.These derivatives exhibited a higher safety index compared with the positive control drug.Among them,12-(trans-4-fluorocinnamoyl)-13-decanoyl phorbol,designated as compound 3c,exhibited the most potent anti-HIV-1 activity(EC_(50)2.9 nmol·L^(−1),CC50/EC_(50)11117.24)and significantly inhibited the formation of syncytium(EC_(50)7.0 nmol·L^(−1),CC50/EC_(50)4891.43).Moreover,compound 3c is hypothesized to act both as an HIV-1 entry inhibitor and as an HIV-1 reverse transcriptase inhibitor.Isothermal titration calorimetry and molecular docking studies indicated that compound 3c may also function as a natural activator of protein kinase C(PKC).Therefore,compound 3c emerges as a potential candidate for developing new anti-HIV drugs. 展开更多
关键词 Phorbol esters Anti-HIV-1 activity Syncytia formation 12-(trans-4-fluorocinnamoyl)-13-decanoyl phorbol Safety index HIV-1 entry inhibitor HIV-1 reverse transcriptase inhibitor PKC activator
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HPLC同时测定安息香中3种化学成分的含量
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作者 刘瑶 李碧君 王峰 《中国实验方剂学杂志》 CAS CSCD 北大核心 2016年第16期40-43,共4页
目的:建立HPLC同时测定安息香中香草醛、松柏醛和trans-[四氢-2-(4-羟基-3-甲氧基苯基)-5-氧代呋喃-3-基]甲基苯甲酸酯含量的方法。方法:采用Phenomenex Luna C18(2)色谱柱(4.6 mm×250 mm,5μm),以甲醇-水为流动相,在1.0 m L·... 目的:建立HPLC同时测定安息香中香草醛、松柏醛和trans-[四氢-2-(4-羟基-3-甲氧基苯基)-5-氧代呋喃-3-基]甲基苯甲酸酯含量的方法。方法:采用Phenomenex Luna C18(2)色谱柱(4.6 mm×250 mm,5μm),以甲醇-水为流动相,在1.0 m L·min-1的流速下,对样品进行梯度洗脱,并在280 nm波长处测定这3种化学成分的含量。结果:3种成分均能达到基线分离,且线性关系良好,加样回收率分别为99.51%,101.25%,100.71%。结论:该方法灵敏、准确、具有良好的稳定性和重复性,可用于同时测定安息香中这3种化学成分的含量,为安息香的质量控制研究提供一定参考。 展开更多
关键词 安息香 香草醛 松柏醛 trans-[四氢-2-(4-羟基-3-甲氧基苯基)-5-氧代呋喃-3-基]甲基苯甲酸酯
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A New Stilbene from Cercis chinensis Bunge 被引量:4
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作者 Yuan LI Dong-Ming ZHANG Shi-Shan YU 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2005年第8期1021-1024,共4页
To study new natural products, we used ODS (YMC, Kyoto, Japan) and silica gel column chromatography to separate compounds in Cercis chinensis Bunge (Leguminosae). A new stilbene, trans- 3, 5, 3', 4'-tetrahydroxy... To study new natural products, we used ODS (YMC, Kyoto, Japan) and silica gel column chromatography to separate compounds in Cercis chinensis Bunge (Leguminosae). A new stilbene, trans- 3, 5, 3', 4'-tetrahydroxy-4-methylstilbene (1), along with 10 known compounds, namely piceatannol (2), dihydromyricetin (3), catechin (4), dihydrorobinetin (5), menisdaurin (6), lithospermoside (7), teatannin (8), dasycarponin (9), β-sitosterol (10), and daucosterin (11), was isolated from C. chinensis. Their structures were elucidated on the basis of spectroscopic evidence. Compounds 2-6 and 9 were isolated from the genus Cercis Linn. for the first time. 展开更多
关键词 Cercis chinensis LEGUMINOSAE trans-3 5 3' 4'-tetrahydroxy-4-methylstilbene.
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