期刊文献+
共找到45篇文章
< 1 2 3 >
每页显示 20 50 100
Synthesis,Structure and DFT Calculations of a Novel Copper(Ⅱ)Complex Based on Tert-butyl 2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate 被引量:3
1
作者 程泽英 胡慧萍 +3 位作者 杨金鹏 邱雪景 王彩霞 姬广富 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第5期795-804,共10页
A novel copper(Ⅱ) complex with tert-butyl 2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate(ampy) was synthesized and structurally characterized by elemental analysis, FT-IR spectrum, electrospray ioniza... A novel copper(Ⅱ) complex with tert-butyl 2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate(ampy) was synthesized and structurally characterized by elemental analysis, FT-IR spectrum, electrospray ionization-mass spectrometry, UV-vis spectrum and single-crystal X-ray diffraction, respectively. A mononuclear copper(II) complex with ampy, [Cu(ampy)Cl2](1), was formed irrespective of the metal-to-ligand molar ratios([Cu2+]:[ampy] = 0.5:1, 1:1, and 2:1) as a single product. Complex 1 crystallizes in the orthorhombic system, space group Pbca with a = 12.343(2), b = 18.928(3), c = 20.058(4) A, V = 4686.1(14) A3, Z = 8, Dc = 1.3349(4) g/cm3, F(000) = 1920, S = 1.016, R = 0.0693 and w R = 0.1721 for 3151 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that the central copper(II) ion is bound by pyridyl N, tertiary amine N and carbonyl O atoms of the quadridentate ampy as well as two Cl anions, constructing a slightly distorted octahedral geometry. Complex 1 further constructs a stable 3D supramolecular architecture by intermolecular C–H…Cl hydrogen bonds. In addition, the molecular geometry was calculated by density functional theory(DFT/B3LYP) method with the basis sets(6-31+G(d,p) for H, C, N, O and Cl atoms, and LANL2 DZ for Cu atom, respectively). The calculated results show that the optimized geometrical parameters are in good agreement with the experimental data. Natural bond orbital(NBO) analysis and frontier molecular orbitals(FMOs) analysis were investigated at the same level. 展开更多
关键词 copper(Ⅱ) complex crystal structure tert-butyl2-[N-(tert-butyloxycarbonylmethyl)-2-picolyamino]acetate (ampy) DFT calculation
下载PDF
Diurnal emission of herbivore-induced(Z)-3-hexenyl acetate and allo-ocimene activates sweet potato defense responses to sweet potato weevils
2
作者 XIAO Yang-yang QIAN Jia-jia +4 位作者 HOU Xing-liang ZENG Lan-ting LIU Xu MEI Guo-guo LIAO Yin-yin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第6期1782-1796,共15页
The sweet potato weevil(Cylas formicarius(Fab.)(Coleoptera: Brentidae)) is a pest that feeds on sweet potato(Ipomoea batatas(L.) Lam.(Solanales: Convolvulaceae)), causing substantial economic losses annually. However,... The sweet potato weevil(Cylas formicarius(Fab.)(Coleoptera: Brentidae)) is a pest that feeds on sweet potato(Ipomoea batatas(L.) Lam.(Solanales: Convolvulaceae)), causing substantial economic losses annually. However, no safe and effective methods have been found to protect sweet potato from this pest. Herbivore-induced plant volatiles(HIPVs)promote various defensive bioactivities, but their formation and the defense mechanisms in sweet potato have not been investigated. To identify the defensive HIPVs in sweet potato, the release dynamics of volatiles was monitored.The biosynthetic pathways and regulatory factors of the candidate HIPVs were revealed via stable isotope tracing and analyses at the transcriptional and metabolic levels. Finally, the anti-insect activities and the defense mechanisms of the gaseous candidates were evaluated. The production of(Z)-3-hexenyl acetate(z3HAC) and allo-ocimene was induced by sweet potato weevil feeding, with a distinct circadian rhythm. Ipomoea batatas ocimene synthase(IbOS) is first reported here as a key gene in allo-ocimene synthesis. Insect-induced wounding promoted the production of the substrate,(Z)-3-hexenol, and upregulated the expression of IbOS, which resulted in higher contents of z3HAC and allo-ocimene,respectively. Gaseous z3HAC and allo-ocimene primed nearby plants to defend themselves against sweet potato weevils. These results provide important data regarding the formation, regulation, and signal transduction mechanisms of defensive volatiles in sweet potato, with potential implications for improving sweet potato weevil management strategies. 展开更多
关键词 sweet potato (Z)-3-hexenyl acetate allo-ocimene defense signaling
下载PDF
Synthesis, Structure and Quantum Mechanical Calculations of Methyl 2-(5-((Quinolin-8-yloxy)-methyl)-1,3,4-oxadiazol-2-ylthio)-acetate
3
作者 AAMER SAEED FOUZIA PERVEEN +2 位作者 NAEEM ABBAS SIDRA JAMAL ULRICH FL?RKE 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第6期858-870,共13页
The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data a... The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes from a methanol solution in the triclinic space group Pi with unit cell dimensions a = 7.4509(9), b = 10.2389(12), c = 12.2299(15)A, a = 74.771(2), β = 77.956(2), 7 = 69.263(2)°, V = 834.98(17) A3 and Z = 2. In order to gain some valuable insights into the molecular structure, the quantum mechanical calculations were performed using both HF and time-dependent density functional theory at the B3LYP/6-31G(d,p) level. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartree-Fock (HF) and density functional theory (DFT) with the 6-31G(d) basis set. The calculated results show that the DFT and HF can well reproduce the structure of the title compound. The energetic behavior of the title compound was examined using the B3LYP method with the 6-31G(d) basis set. The harmonic vibrational frequencies calculated have been compared with the experimental FTIR and FT-Raman spectra. The restricted Hartree-Fock and density functional theory-based nuclear magnetic resonance (NMR) calculation procedure was also performed, and it was used for assigning the 13C and 1H NMR chemical shifts of the title compound. Moreover, molecular electrostatic potential and thermodynamic parameters of the title compound were investigated by theoretical calculations. 展开更多
关键词 methyl 2-(5-((quinolin-8-yloxy)methyl)-1 3 4-oxadiazol-2-ylthio)acetate CRYSTALSTRUCTURE CONFORMER quantum chemical calculations vibrational studies
下载PDF
Synthesis,Characterization,X-ray Crystal Structure and Safener Activity of Chiral 2-(3-Methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)-2-oxoethyl Acetate
4
作者 叶非 程阳 +2 位作者 吴世龙 孙长迎 付颖 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第11期1694-1699,共6页
The new title compound, chiral 2-(3-methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)- 2-oxoethyl acetate, has been synthesized via reduction, cyclization and acylation reaction. The structure of the product has been conf... The new title compound, chiral 2-(3-methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)- 2-oxoethyl acetate, has been synthesized via reduction, cyclization and acylation reaction. The structure of the product has been confirmed by IR, 1H NMR, 13C NMR, LC-MS (ESI) and single-crystal X-ray diffraction. (R)-2-(3-methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)-2-oxoethyl acetate crystallizes in monoclinic, space group P21/c with a = 11.867(2), b = 8.4087(2), c = 14.325(6) A^°, β = 117.59(2)°, Z = 4, V = 1266.9(6) A^°3, Dc = 1.307 g/cm^3, F(000) = 528, μ(MoKα) = 0.097 mm-1, R = 0.0453 and wR = 0.1237; (S)-2-(3-methyl-2,3-dihydrobenzo[b][1,4]oxazin-4-yl)-2-oxoethyl acetate belongs to the triclinic system, space group P with a = 8.2647(17), b = 8.7034(17), c = 9.5479(19) A^°, α = 105.33(3), β = 100.95(3), γ = 105.14(3)°, Z = 2, V = 614.1(2) A^°3, Dc = 1.348 g/cm^3, F(000) = 264, μ(MoKα) = 0.10 mm-1, R = 0.0613 and wR = 0.1037. Both of the molecules prefer to form crystal packing through C–H…O hydrogen bonds. 展开更多
关键词 synthesis single crystal CHIRAL 2-(3-methyl-2 3-dihydrobenzo[b][1 4]oxazin-4-yl)-2-oxoethyl acetate
下载PDF
Preparation, Characterization and Catalytic Performance of La-SO_4^(2-)/SBA-15 in Esterification of Acetic Acid with n-Butanol 被引量:12
5
作者 TIAN Zhi-ming DENG Qi-gang +1 位作者 SUN Hui ZHAO De-feng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第3期357-361,共5页
La-SO42-/SBA-15 was synthesized with various amounts of lanthanum via incipient-wetness impregnation. Characterization was done by X-ray diffraction(XRD), transmission electron micrographs(TEM), nitrogen adsorptio... La-SO42-/SBA-15 was synthesized with various amounts of lanthanum via incipient-wetness impregnation. Characterization was done by X-ray diffraction(XRD), transmission electron micrographs(TEM), nitrogen adsorption, FTIR spectroscopic analysis, thermogravimetric analysis, and the total amount of acidity of catalyst was estimated by TPD of NH3. The results indicate that lanthanum has been incorporated into SBA-15 molecular sieve. The prepared materials(La-SO42-/SBA-15) keep the highly ordered mesoporous two-dimensional hexagonal structure and do not change the mesoporous channel structure of the support SBA-15. The catalyst showed best catalytic activity in the synthesis of n-butyl acetate. The optimum conditions of the esterification by orthogonal experiments were studied: the molar ratio of n-butanol to acetic acid 1:1.2, the amount of catalyst 7.5%, reaction time 80 min. The yield of n-butyl acetate could reach 93.2% under the optimum conditions. The catalyst was recyclable, cost effective and environmental friendly. 展开更多
关键词 SBA-15 molecular sieve La-SO462-/SBA-15 CATALYSIS n-Butyl acetate ESTERIFICATION
下载PDF
Synthesis,Crystal Structure and Antitumor Activity of a Novel Zn(Ⅱ)Complex with 2-(Nicotinoyloxy)acetic Acid Ligand 被引量:1
6
作者 台夕市 郭洪梅 郭芊沁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第7期1052-1056,共5页
A novel Zn(Ⅱ) complex, [ZnL2(H2O)4]·H2O(1, HL = 2-(nicotinoyloxy)acetic acid), was synthesized using Zn(OAc)2·2H2O and 2-(nicotinoyloxy)acetic acid as raw materials. Its structure has been eluci... A novel Zn(Ⅱ) complex, [ZnL2(H2O)4]·H2O(1, HL = 2-(nicotinoyloxy)acetic acid), was synthesized using Zn(OAc)2·2H2O and 2-(nicotinoyloxy)acetic acid as raw materials. Its structure has been elucidated by elemental analysis, IR and single-crystal X-ray diffraction. The structural analysis revealed that complex 1 crystallizes in triclinic, space group P1 and the Zn(Ⅱ) atom is six-coordinated with two N atoms from two different 2-(nicotinoyloxy)acetate anion ligands and four O atoms from coordinated water molecules. Complex 1 forms a 3D network structure by O–H···O hydrogen bonds. The antitumor activities of 2-(nicotinoyloxy)acetic acid ligand and its Zn(Ⅱ) complex were evaluated against human lung adenocarcinoma A549 cells, human hepatoma SMMC-7721 cells and human colon carcinoma Wi Dr cells. 展开更多
关键词 2-(nicotinoyloxy)acetic acid ligand Zn(Ⅱ) complex SYNTHESIS crystal structure antitumor activity
下载PDF
Synthesis,Structure,and Surface Photo-electric Properties of a New Zn(Ⅱ)Coordination Complex Constructed from 2-(1H-benzotriazol-1-yl)acetic Acid and 1,10-Phenanthroline Ligands 被引量:2
7
作者 李家明 史忠丰 何坤欢 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第1期135-142,共8页
A new binuclear Zn^Ⅱ coordination complex,Zn2(bta)(phen)2(Cl)3(1,Hbta = 2-(1Hbenzotriazol-1-yl)acetic acid and phen = 1,10-phenanthroline),has been synthesized and characterized by single-crystal X-ray diff... A new binuclear Zn^Ⅱ coordination complex,Zn2(bta)(phen)2(Cl)3(1,Hbta = 2-(1Hbenzotriazol-1-yl)acetic acid and phen = 1,10-phenanthroline),has been synthesized and characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental,and photoluminescent analysis.Complex 1 crystallizes in triclinic system,space group P1 with a = 9.3040(19),b = 10.694(2),c =16.841(3) A°,α = 101.18(3),β = 105.77(3),γ = 91.72(3)°,V= 1575.8(5) A°3,C(32)H(22)Zn2Cl3N7O2,Mr =773.66,Dc = 1.631 g/cm^3,Z = 2,F(000) = 780,μ = 1.820 mm^-1,the final R = 0.1238 and wR =0.1131.X-ray diffraction analyses indicate that 1 displays two crystallographic independent Zn^Ⅱmetal centers with a distorted tetragonal pyramidal(ZnN4O) and a tetrahedral(ZnNCl3) geometries,respectively.The phen serves as a common N,N'-bidentate ligand,and the bta^- as a unique N,O-bridged ligand in 1.In the crystal,1 forms a stable 3D supramolecular architecture by trifurcated hydrogen bonding C-H…C1 interactions and C-H…π,π…π stacking.1 showed photo-electric conversion properties. 展开更多
关键词 photo-electric property zinc(Ⅱ) complex 2-(1H-benzotriazol-1-yl)acetic acid synthesis crystal structure
下载PDF
Acetalation and Ketalation Catalyzed by SO_4^(2-)/TiO_2-MoO_3
8
作者 YANG Shui-jin BAI Ai-min DONG Jing-hua SUN Ju-tang 《合成化学》 CAS CSCD 2004年第z1期138-138,共1页
关键词 acetal ketal SO42-/TiO2-MoO3 catalysis.
下载PDF
Synthesis of 2-(Benzodioxol-2-yl)acetic Acids as PPARδAgonists
9
作者 Jian Lei KANG Zhi Bing ZHENG +2 位作者 Dan QIN Li Li WANG Song LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1013-1016,共4页
A new series of compounds, 2-(benzodioxol-2-yl)acetic acids, have been synthesized. Their structures were confirmed by MS and 1H-NMR. The preliminary pharmacological screening showed that these compounds exhibited p... A new series of compounds, 2-(benzodioxol-2-yl)acetic acids, have been synthesized. Their structures were confirmed by MS and 1H-NMR. The preliminary pharmacological screening showed that these compounds exhibited potent human PPARδ agonist activities. 展开更多
关键词 PPARδ agonists 2-(benzodioxol-2-yl)acetic acids synthesis.
下载PDF
Synthesis and Crystal Structure Analysis of 2-(3,5-Di-tert-butyl-2-hydroxyphenyl)-2-(3,4- dimethylphenyl) Acetic Acid Dimethylamine Salt
10
作者 程杰 成昌梅 +3 位作者 何娟 尚培华 王如骥 赵玉芬 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第4期414-418,共5页
A new compound 2-(3,5-di-tert-butyl-2-hydroxyphenyl)-2-(3,4-dimethylphenyl) acetic acid dimethylamine salt ([NH2(CH3)2][C24H31O3]) was synthesized and structurally determined. It is of monoclinic system, space... A new compound 2-(3,5-di-tert-butyl-2-hydroxyphenyl)-2-(3,4-dimethylphenyl) acetic acid dimethylamine salt ([NH2(CH3)2][C24H31O3]) was synthesized and structurally determined. It is of monoclinic system, space group P21/c with a = 14.731(2), b = 10.1185(10), c = 17.065(2) A^°, β = 98.293(10)° ,Z = 4, V = 2517.0(6)A^°^3, Dc = 1.091 g/cm^3, F(000) = 904 and Mr= 413.58. The dihedral angle defined by two benzene rings is 98.23°. 展开更多
关键词 2-(3 5-di-tcrt-butyl-2-hydraxyphenyl)-2-(3 4-dimethylphenyl) acetic acid dimethylamine salt synthesis X-ray diffraction crystal structure
下载PDF
Synthesis and Molecular Structure of Acetic Acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester
11
作者 WEI Hui-Qin ZENG Run-Sheng WU Gui-Ping WANG Bao-An ZOU Jian-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第8期1014-1018,共5页
The title compound, acetic acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin- 2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester 8 (C28H28N2O10, Mr = 552.54), has been synthesized and its crystal structure was determined ... The title compound, acetic acid-3,5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin- 2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester 8 (C28H28N2O10, Mr = 552.54), has been synthesized and its crystal structure was determined by X-ray diffraction analysis. It crystallizes in monoclinic, space group P21, a = 10.060(8), b = 5.648(4), c = 24.11(2)A, β = 91.078(10)°, Z = 2, V= 1369.9(19)A^3, Dc = 1.339 g/cm^3,μ(MoKa) = 1.03 cm^-1, F(000) = 580.00, T =. 193.1 Kx-9 θmax = 25.03, (△/σ)max = 0.0000, Flack = -0.0(24), the final R = 0.0680 and wR = 0.140 (w = 1/[0.0016Fo^2 + 1.00000(Fo^2)]/(4Fo^2)) for 3126 observed reflections (1 〉 20(/)). The pyranoid ring adopts chair conformation in the sugar moiety, and all of the acetyl groups are in the e bond of the pyranoid ring, so the sugar moiety is very stable. 展开更多
关键词 acetic acid-3 5-diacetoxy-2-acetoxymethyl-6-(4-quinoxalin-2-yl-phenoxy)-tetrahydro-pyran-4-yl-ester synthesis crystal structure
下载PDF
气相色谱-质谱法测定化妆品中的氯霉素 被引量:11
12
作者 谢维平 陈春祝 +1 位作者 黄盈煜 傅晖蓉 《色谱》 CAS CSCD 北大核心 2006年第6期659-659,共1页
关键词 气相色谱-质谱(GC-MS) 乙酸酐(acetic anhydride) 氯霉索(chloramphenicol) 衍生化(derivatization) 化妆品(cosmetics)
下载PDF
β-谷甾醇乙酸酯对脂质膜结构稳定性的影响 被引量:5
13
作者 侯丽芬 宗珊盈 +3 位作者 张海臣 潘丽 王宏雁 谷克仁 《食品与机械》 北大核心 2019年第9期20-25,共6页
通过薄膜-超声法制备β-谷甾醇乙酸酯脂质体,考察其不同掺入浓度对脂质体粒径、PDI和储藏稳定性的影响,探究β-谷甾醇乙酸酯与磷脂在膜中的相互作用。试验结果表明,脂质体在β-谷甾醇乙酸酯添加量为2,4 mg时,与相同条件下的β-谷甾醇脂... 通过薄膜-超声法制备β-谷甾醇乙酸酯脂质体,考察其不同掺入浓度对脂质体粒径、PDI和储藏稳定性的影响,探究β-谷甾醇乙酸酯与磷脂在膜中的相互作用。试验结果表明,脂质体在β-谷甾醇乙酸酯添加量为2,4 mg时,与相同条件下的β-谷甾醇脂质体Size和PDI相一致;4℃下储藏30 d,低掺入量的β-谷甾醇乙酸酯脂质体具有较好的储藏稳定性;采用FTIR检测结果显示β-谷甾醇乙酸酯掺入脂质体中与磷脂的P═O和(CH 3)3 N之间有相互作用;TGA的分析结果也验证了β-谷甾醇乙酸酯在低掺入量时对其构建脂质体膜结构起稳定作用。 展开更多
关键词 β-谷甾醇乙酸酯 脂质体 稳定性 影响
下载PDF
Cloning and expression of two sterol C-24 methyltransferase genes from upland cotton(Gossypium hirsuturm L.) 被引量:8
14
作者 Ming Luo,Kunling Tan,Zhongyi Xiao,Mingyu Hu,Peng Liao,Kuijun Chen Key Laboratory of Biotechnology and Crop Quality Improvement,Ministry of Agriculture Biotechnology Research Center,Southwest University,Chongqing 400716,China 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第6期357-363,共7页
Brassinosteroids (BRs) are an important class of plant steroidal hormones that are essential in a wide variety of physiological processes. Two kinds of intermediates, sitosterol and campesterol, play a crucial role ... Brassinosteroids (BRs) are an important class of plant steroidal hormones that are essential in a wide variety of physiological processes. Two kinds of intermediates, sitosterol and campesterol, play a crucial role in cell elongation, cellulose biosynthesis, and accumulation. To illuminate the effects of sitosterol and campesterol on the development of cotton (Gossypiurn hirsuturm L.) fibers through screening cotton fiber EST database and contigging the candidate ESTs, two key genes GhSMT2-1 and GhSMT2-2 controlling the sitosterol biosynthesis were cloned from developing fibers of upland cotton cv. Xuzhou 142. The full length of GhSMT2-1 was 1,151 bp, including an 8 bp 5'-untranslated region (UTR), a 1,086 bp open reading frame (ORF), and a 57 bp 3'-UTR. GhSMT2-1 gene encoded a polypeptide of 361 amino acid residues with a predicted molecular mass of 40 kDa. The full length of GhSMT2-2 was 1,166 bp, including an 18 bp 5'-UTR, a 1,086 bp ORF, and a 62 bp 3'-UTR. GhSMT2-2 gene encoded a polypeptide of 361 amino acid residues with a predicted molecular mass of 40 kDa. The two deduced amino acid sequences had high homology with the SMT2 from Arabidopsis thaliana and Nicotiana tabacurn. Furthermore, the typical conserved structures characterized by the sterol C-24 methyltransferase, such as region I (LDVGCGVGGPMRAI), region II (IEATCHAP), and region III (YEWGWGQSFHF), were present in both deduced proteins. Southern blotting analysis indicated that GhSMT2-1 or GhSMT2-2 was a single copy in upland cotton genome. Quantitative real-time RT-PCR analysis revealed that the highest expression levels of both genes were detected in 10 DPA (day post anthesis) fibers, while the lowest levels were observed in cotyledon and leaves. The expression level of GhSMT2-1 was 10 times higher than that of GhSMT2-2 in all the organs and tissues detected. These results indicate that the homologue of sterol C-24 methyltransferase gene was cloned from upland cotton and both GhSMT2 genes play a crucial role in fiber elongation. The role of GhSMT2-1 may be more important than that of GhSMT2-2. 展开更多
关键词 cotton fiber sitosterol CAMPESTEROL sterol C-24 methyltransferase GhSMT2-1 GhSMT2-2
下载PDF
MICROBIAL TRANSFORMATION OF 19-HYDROXY-CHOLESTEROL ACETATE OR 19-HYDROXY-β-SITOSTEROL ACETATE TO △~4-19-HYDROXY ANDROST-3, 17-DIONE
15
作者 周维善 殷芝华 王敬一 《Chinese Science Bulletin》 SCIE EI CAS 1991年第16期1386-1387,共2页
The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or... The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or indirect synthesis via estrone of this class of compound. 展开更多
关键词 microbial transform ation 19-hydroxycholesterol acetate 19-hydroxy-β-sitosterol acetate △~4-19-hydroxy androst-3 17-dione.
原文传递
Synthesis of 3-(1-Cyclohexenyl)-2-butanone via Environmentally Friendly Catalysts
16
作者 ZHAO Zhen-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第3期350-354,共5页
We substituted several environmentally friendly catalysts which included HY and H- β zeolites, various cation-exchanged β zeolites, and solid-supported ferric chloride for conventional catalysts for the synth... We substituted several environmentally friendly catalysts which included HY and H- β zeolites, various cation-exchanged β zeolites, and solid-supported ferric chloride for conventional catalysts for the synthesis of 3-(1-cyclohexenyl)-2-butanone from the reaction of ethylidenecyclohexane with acetic anhydride at room temperature. HY zeolite was found to be the most effective for this reaction, and gave the acylated product in a 72% yield under the conditions of n (ethylidenecyclohexane)/ n (acetic anhydride)/ m (HY zeolite)=1 mmol/10 mmol/0 100 g, reaction temperature 25 ℃ and reaction time 2 h. The used HY zeolite can be recovered, regenerated and gave almost the same yield as the fresh one. The lifetime of the HY zeolite is over 80 h. The effect of different factors on the reaction has also been investigated. 展开更多
关键词 ACYLATION ZEOLITE Environmentally friendly catalyst 3-(1-Cyclohexenyl)-2-butanone Ethylidenecyclohexane acetic anhydride Synthesis
下载PDF
The Expression of Cyclooxygenase-2 in Cervical Cancers and Hela Cells Was Regulated by Estrogen/Progestogen
17
作者 李允光 濮德敏 李艳丽 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第4期457-460,共4页
To investigate the relationship between the expression of cyclooxygenase-2 (COX-2) and menstrual cycle, the regulatory effects of 17-β-estradiol (E2) and medroxyprogesterone acetate (MPA) on the expression of C... To investigate the relationship between the expression of cyclooxygenase-2 (COX-2) and menstrual cycle, the regulatory effects of 17-β-estradiol (E2) and medroxyprogesterone acetate (MPA) on the expression of COX-2 in cervical cancer Hela cells were examined. Cervical cancer specimens were obtained from 47 pre-menopausal patients. The phase of menstrual cycle was determined by case history and HE staining of uterine endometrium. COX-2 was immunohistochemically stained by SABC staining and the staining intensity was determined with computerized image analysis system. Hela cells were incubated with alcohol, E2, E2+MPA, MPA for 12, 24 and 48 h respectively. The expression of COX-2 in Hela cells was detected by Western blotting and reverse transcriptase-polymerase chain reaction (RT-PCR). Our results showed that the expression of COX-2 was significantly higher during proliferative phase than secretory phase (P〈0.05), but there was no difference in the positive rate between proliferative phase and secretory phase (P〉0.05). Incubation with E2 could significantly enhance the expression of COX-2 continually. On the contrary, E2+MPA and MPA alone could decrease the expression of COX-2 as compared with the control and E2 group (P〈0.05 and P〈0.01 respectively). It is concluded that the expression of COX-2 in cervical cancer of pre-menopausal patients and Hela cells was regulated by estrogen/progestogen. 展开更多
关键词 cervical cancer CYCLOOXYGENASE-2 menstrual cycle 17-β-ESTRADIOL medroxyprogesterone acetate
下载PDF
A Sensitive HPLC-MS/MS Analysis of Dencichine in Rat Plasma and Its Application to Pharmacokinetics
18
作者 Chen Qian Yanjuan Yuan +4 位作者 Xuejun He Jing Liu Qing Shao Hua Wu Hongqun Qiao 《American Journal of Analytical Chemistry》 2012年第8期596-603,共8页
In order to quantitate dencichine in biological samples, a selective and sensitive method for the determination of dencichine in rat plasma based on high-performance liquid chromatography-tandem mass spectrometry (HPL... In order to quantitate dencichine in biological samples, a selective and sensitive method for the determination of dencichine in rat plasma based on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed and validated. (l)-2-amino-3-(carboxymethylthio)propionic acid was used as the internal standard (I.S.). After a protein precipitation extraction with acetonitrile, dencichine and the I.S. were chromatographed on an Xterra MS-C18 column. The mobile phase was consisted of 20mmol/L ammonium acetate solution-acetonitrile (35:65, V/V) at a flow rate of 0.2 mL/min. The detection was performed on a triple quadrupole mass via electrospray ionization (ESI) source in the positive mode. The intra- and inter-day precision (relative standard deviation, R.S.D.) values of dencichine were below 6.7%. The extraction recoveries were up 85%. The lower limit of quantification was 20 ng/ml, which was sensitive enough to detect the analyte. The HPLC-MS/MS method was successfully applied to the pharmacokinetic study after an intravenous administration of dencichine in Sprague-Dawley (SD) rat. 展开更多
关键词 DENCICHINE (L)-2-Amino-3-(Carboxymethylthio)Propionic Acid HPLC-MS/MS PHARMACOKINETIC Ammonium acetate Solution-acetonitrile (35:65 V/V) Mobile Phase
下载PDF
Enantioselective Resolution of (±)-l-Phenylethyl Acetate by Using the Whole Cells of Deep-sea Bacterium Bacillus sp. DL-2 被引量:2
19
作者 DONG Lu XU Yongkai +2 位作者 ZHANG Yun SUN Aijun HU Yunfeng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2019年第5期792-798,共7页
Bacillus sp. DL-2 was isolated from the deep sea of the Western Pacific and further utilized as novel biocatalysts to efficiently asymmetrically hydrolyze (±)-1-phenylethyl acetate. After the optimization of hydr... Bacillus sp. DL-2 was isolated from the deep sea of the Western Pacific and further utilized as novel biocatalysts to efficiently asymmetrically hydrolyze (±)-1-phenylethyl acetate. After the optimization of hydrolytic reactions, chiral chemicals (R)1-phenylethanol and (S)-l-phenylethyl acetate were obtained with high optical purities (96% and 99.8%, respectively). Our research is about the asymmeric hydrolysis of (±)-1-phenylethyl acetate using whole-cell biocatalysts. In addition, the optical purity of (S)-l-phenylethyl acetate generated through the kinetic resolution of (±)-1-phenylethyl acetate using the whole-cells of Bacillus sp. DL-2 was the highest report so far. Using the whole cells of deep sea bacterium Bacillus sp. DL-2 as the biocatalysts is an enviromnentally friendly method and will play critical roles in industrial asymmetric synthesis. 展开更多
关键词 DEEP-SEA MICROORGANISM WHOLE-CELL BIOCATALYST Asymmetric hydrolysis (R)-1-Phenylethanol (S)-1-Phenylethyl acetate
原文传递
Clinical Study on Treatment of Advanced Non-small Cell Lung Cancer by Arsenious Acid Combined with Tα-1 Thymus Peptide and Megestrol Acetate
20
作者 GUO Yue-feng(郭岳峰) +1 位作者 JIAO Zhi-min(焦智民) 《Chinese Journal of Integrative Medicine》 SCIE CAS 2002年第4期262-266,共5页
Objective: To observe the therape utic effect of arsenious acid combined with Tα-1 thymus peptide and megestro l acetate on advanced non-small cell lung cancer.Methods: Nintey-two patients were divided randomly into... Objective: To observe the therape utic effect of arsenious acid combined with Tα-1 thymus peptide and megestro l acetate on advanced non-small cell lung cancer.Methods: Nintey-two patients were divided randomly into the tr eated group( n =45) and the control group( n =47). The treated group were tr eated with arsenious acid combined with Tα-1 thymus peptide and megestrol ac etate, and the control group were treated with chemotherapy in the NP protocol .Results: (1) Therapeutic effect :In the 36 patients of the treated group, 2 were evaluated as CR, 8 as PR, 9 as MR, 8 as SD and 9 as PD, the CR+PR rate being 27.7% (10/36), while in the 40 patients of the control group, the co rresponding numbers were 3, 10, 11, 9, 7 and 32.5% (13/40). Comparison between t he CR+PR rate between the two groups showed insignificant difference ( P >0.05 ). (2)Clinical benefit rate: The positive rate of Karnofsky scores in the treate d group and the control group was 44.4% and 20.0% respectively; and the positive rate of body weight in the two groups was 33.3% and 12.5% respectively, the dif ference between the two groups was significant ( all P <0.05). (3)Changes of T- cell subsets and NK cell activity: CD4 and CD4/CD8 ratio after treatment i n the treated group increased significantly ( P <0.05), while in the control group, CD3, CD4, CD4/CD8 ratio and NK cell activity all lowered significantly ( P <0.01). Comparison between the two groups after treatment showed significa nt difference in CD4, CD4/CD8 ratio and NK cell activity, with those in the trea ted group all higher than those in the control group ( P <0.01). (4)Adeverse -reaction: No serious adverse reaction was found in both two groups. (5)Media n survival period:The treated group was 30 weeks and that in the control group w as 28.5 weeks, and the difference between the two groups was insignificant ( P >0.05).Conclusion: Arsenious acid combined with Tα-1 thymus peptide and megestrol acetate was a relatively effective scheme with low toxicity in tre ating advanced NSCLC. 展开更多
关键词 arsenious acid -1 thymus peptide megestrol acetate non-small cell lung cancer
原文传递
上一页 1 2 3 下一页 到第
使用帮助 返回顶部