检索结果-南通市图书馆

Synthesis and x-ray crystal structure of a Methylene-bridged Glycoluril Dimer

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2010年第1期29卷 47-50页

作者：佘能芳吴彦东孙静静吴安心 Key Laboratory of Pesticide & Chemical Biology Ministry of EducationCollege of ChemistryCentral China Normal University

The synthesis and x-ray crystal structure of a methylene-bridged glycoluril dimer 2 was *** methylene-bridged glycoluril dimer 2（C38H36Br4N8O12,Mr=1116.35） crystallizes in space group P1 with a=10.5802（6）,b=16.8469（9）,c=24.7673（14） ,α=98.00,β=96.263（1）,γ=101.606（1）o,V=4239.3（4）3,Z=4,Dc=1.749 g/cm3,μ=3.869 mm-1 and F（000）=*** crystallizes in an S-shaped conformation that displays two ethoxycarbonyl groups on each face of the molecule.

关键词： methylene-bridged glycoluril dimer x-ray crystal structure S-shape

Synthesis and crystal structure of a One-dimensional Ladder-like Complex [Cu_2(L)(dca)_2]_n(dca = [N(CN)_2]～-,L=1,4-Bis(3-furanyl)-2,3-diaza-1,3-butadiene)

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2008年第9期27卷 1069-1072页

作者：赵琦华赵辉杜琳方瑞斌 Department of Chemistry Key Laboratory of Medicinal Chemistry for Natural ResourceMinistry of EducationYunnan University

A new Cu（I）-dicyanamide with formula [Cu2（L）（dca）2]n （dca = dicyanamide anion, L = 1,4-bis（3-furanyl）-2,3-diaza-1,3-butadiene） has been synthesized and structurally characterized. The complex crystallizes in the monoclinic system, space group P21/n with a = 9.271（2）, b = 7.7355（16）, c = 11.967（3）A,β = 102.693（3）°, V= 837.3（3）A^3, Z = 4, Mr = 223.68, Dc = 1.775 g/cm^3,μ（MoKa） = 2.567 mm^-1, F（000） = 444, R = 0.0782 and wR = 0.2582 for 951 observed reflections （I 〉 2σ（I））. Single-crystal x-ray analysis reveals that the copper atom is three-coordinated by two nitrogen atoms from two dicyanamide anions and another one from the ligand, and each copper atom is connected by two [N（CN）2] anions to form an infinite double-stranded bridge fashion leading to 1D ladder-like motifs.

关键词： copper(I) complex dieyanamide x-ray crystal structure

Air-stable diradical dications with ferromagnetic interaction exceeding the thermal energy at room temperature: from a monomer to a dimer

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2018年第3期61卷 300-305页

作者： Wenqing Wang Lei Wang Sheng Chen Wenbang Yang Zaichao Zhang xinping Wang State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Collaborative Innovation Center of Advanced Microstructures Nanjing University School of Chemistry and Chemical Engineering Huaiyin Normal University

Two tetraazacyclophane dications(1^(2+) and 2^(2+)) with different remote substituents have been synthesized, isolated and *** electronic structures and physical property were studied by various spectroscopic techniques, single crystal x-ray diffraction,super conducting quantum interference device(SQUID) measurements and theoretical calculations. The dications have triplet ground states with ferromagnetic interaction exceeding the thermal energy at room temperature. The solid-state structures of these species were tunable by substituent effect, with 1^(2+) as a monomer and 2^(2+) as a dimer.

关键词： diradical dication triplet ground state ferromagnetic interaction x-ray crystal structure

Syntheses, characterization, and luminescence of two lanthanide complexes [Ln_2(acetate)_6(H_2O)_4]·4H_2O (Ln=Tb(1), Sm(2))

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2008年第2期26卷 178-184页

作者：于琼燕周秀霞刘茂胜陈键侨周正元殷霞蔡跃鹏 School of Chemistry and Environment South China Normal UniversityGuangzhou 510006 China

Two dinuclear compounds [Ln2（acetate）6（H2O）4]-4H2O （Ln=Tb（1）, Sm（2）） were obtained by the hydrothermal reaction of Ln2O3 with malonic acid at 150 ℃. Both compounds were characterized by elemental analyses, infrared spectra, and single crystal x-ray diffraction. The results showed that complexes 1 and 2 were isomorphous and crystallize in triclinic space group P 1. The coordination geometry around Ln（Ⅲ） ions in the complexes 1 and 2 was a distorted tricapped trigonal prism with a nine coordination. In the crystal, the molecular organization was further stabilized by well-defined weak hydrogen bonding interactions between the neutral dinuclear molecular units that led to the formation of a three-dimensional network. The fluorescence properties of the two complexes 1 and 2 in organic solvents were also studied. The results show that the ligand acetate favored energy transfer to the emitting energy level of Tb（Ⅲ） in complex 1. Some factors that influence the fluorescent intensity were also discussed in the article.

关键词： rare earth dinuclear complexes x-ray crystal structure malonic acid fluorescence rare earths

Synthesis, structure Characterization, and Cu^(2+) Recognition of 3-{[3-(Phenylsulfonamido)benzoyl]methylidene}-3,4-dihydroquinoxaline-2(1H)-one

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2006年第6期22卷 747-752页

作者： LI xue-mei ZENG Cheng-chu NIU Li-ting YAN Hong ZHENG Da-wei ZHONG Ru-gang College of Life Science ＆ Bioengineering Beijing University of Technology Beijing 100022 P. R. China

Aryl diketo acid derivatives are one of the most promising HIV-1 integrase（IN） inhibitors. With a view to substitute the critical diketo acid pharmacophore with the diketo benzimidazole unit, the coupling reaction of compound 4 with o-phenylenediamine was carried out. However, the reaction product, compound 5, was confirmed to be 3-{ [ 3- （phenylsulfonamido） benzoyl] methylidene t -3,4-dihydroquinoxaline-2 （1H） -one rather than the 2-benzimidazole derivative by using x-ray diffraction. Owing to its low solubility in water, the evaluation of the anti-HIV IN activity of the synthesized compound 5 could not be carried out. Consequently, the ion-binding properties of compound 5 in the absence of HIV-1 IN were investigated with UV-Vis spectroscopy in organic solvents. The results show that such a compound can selectively recognize Cu^2＋.

关键词： Diketo acid Quinoxalone derivative x-ray crystal structure Cu^2+ recognition

Inactivity of YGL082W in vitro due to impairment of conformational change in the catalytic center loop

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2020年第2期63卷 237-243页

作者： Lining Lu Yu Guo Tian Wang Lujun Liang Suwen Zhao Feng Wang Lei Liu Tsinghua-Peking Center for Life Sciences Key Laboratory of Bioorganic Phosphorus Chemistry&Chemical Biology(Ministry of Education)Center for Synthetic and Systems BiologyState Key Laboratory of Chemical Oncogenomics(Shenzhen)Department of ChemistryTsinghua UniversityBeijing 100084China School of Life Science Beijing Institute of TechnologyBeijing 100081China iHuman Institute School of Life Science and TechnologyShanghaiTech UniversityShanghai 201210China

MINDY-1 is a recently discovered new family of deubiquitinating enzymes(DUB),but one of its yeast homologs,YGL082 W,does not show any DUB activity in *** alignment shows that YGL082 W possesses the correct catalytic triad,and yet did not catalyze either the hydrolysis of di-ubiquitin,crosslinking with C-terminally propargylated ubiquitin,or hydrolysis of *** obtaining a crystal structure of the catalytic domain of YGL082 W,we identified an interesting difference between the catalytic center loop of YGL082 W and that of its human homolog *** the conformation of the catalytic center loop was previously reported to be important for the deubiquitination activity of MINDY-1,we hypothesized that Glu27(instead of the corresponding Pro136 in MINDY-1) of the catalytic center loop of YGL082 W may impair the conformational change and account for the lack of *** hypothesis was supported by homology modeling and molecular dynamics simulations,which showed that the Pro-to-Glu mutation(P136 E mutation for MINDY-1) creates a hydrogen bond that inhibits the conformation change of the catalytic center loop of *** experiments through site-directed mutation validated this hypothesis,showing that the P27 E mutation caused MIY1(a homologous active DUB from yeast) to lose activity.

关键词： deubiquitinating enzymes(DUB) enzymology x-ray crystal structure molecular dynamics

Synthesis of (3aS,6aR)-1,3-Dibenzyl-tetrahydro-1H- thieno[3,4-d]-imidazole-2(3H)-one-4-ylidenepentanoic Acid and Characterization of Its crystal

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2004年第6期23卷 507-510页

作者：袁建莉王静梅陈芬儿 Department of Chemistry Fudan University Shanghai 200433 China Research Center for Analysis and Measurement Fudan University Shanghai 200433 China

The intermediate of d-biotin, (3aS,6aR)-1,3-dibenzyltetrahydro-1H-thieno[3,4- d]-imidazole-2(3H)-one-4-ylidenepentanoil acid was synthesized from (3aS,6aR)-1,3-dibenzylte- trahyro-4H-thieno[3,4-d]-imidazole-2,4(1H)-dione by using the Grignard reaction. The structure of 3 was characterized by IR, 1H NMR and MS, and the absolute configuration was further confirmed by x-ray crystal structure analysis. Compound 3 crystallizes in monoclinic, space group P21 with a = 11.030(2), b = 7.783(2), c = 12.797(2) , b = 93.44(1)o, Z = 2, Mr = 422.53 (C24H26N2O3S), V = 1096.3(6) 3, = 0.177 mm-1, Dc = 1.280 g/cm3, F(000) = 448 and T = 293(2) K. The final R = 0.0737 and Rw = 0.1974 for 1009 observed reflections with I >2s(I).

关键词： Grignard reaction, synthesis x-ray crystal structure

A New Route to Z-5-Fluoro-2-methyl-1- （p-methylsulfinylbenzylidene）-3-indenylacetic Acid and Its x-ray Diffraction Analysis

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2006年第10期24卷 1443-1446页

作者：曾卓陈超森金桂芳赵经纬朱士正 College of Chemistry and Environment South China Normal University Guangzhou Guangdong 510931 China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Science Shanghai 200032 China

The title compound （Sulindac） was prepared from the corresponding sulfinyl compound p-methylsulfinylbenzyl bromide by four-step reaction. The sole product （Z）-5-fuoror-2-methyl-l-（p-methylsulfinylbenzylidene）-3-indenyl acetic acid （Sulindac） was obtained and the E isomer of it was not found. x-ray single crystal diffraction analysis showed that the strong intermolecular hydrogen bonding and weak intermolecular hydrogen bonding coexisted in Sulindac.

关键词： p-methylsulfinylbenzyl bromide Z configuration x-ray crystal structure intermolecular hydrogen bonding

Guajamers A-I, Rearranged Polycyclic Phloroglucinol Meroterpenoids from Psidium guajava Leaves and Their Antibacterial Activity

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2021年第5期39卷 1129-1137页

作者： Ji-Wu Huang Chuang-Jun Li Jing-Zhi Yang Chuan Li Yu Zhang Ke Liu Yue Yu Jian-Dong Jiang Dong-Ming Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Eight new polycyclic phloroglucinol meroterpenoids guajamers A-H(1-8),a methylated benzoylphloroglucinol meroterpenoid guajamer I(9)representing a new skeleton,and two known analogues(10 and 11)were isolated from the leaves of Psidium *** structures of new molecules were elucidated by detailed analysis of spectroscopic data,and those of 1,2,8,and 9 were unambiguously confirmed by single-crystal x-ray diffraction ***,compounds 1-8 were sesquiterpene and monoterpene-based meroterpenoids with rearranged skeletons,while compound 9 was the first case of 3-alkyl-5-formyl-benzoylphloroglucinol-coupled sesquiterpene containing an unusual C-l-spiro-fused 6/6/9/4 polycyclic *** addition,all the isolated compounds were evaluated for their antibacterial activity against three bacterial strains,and most of them(compounds 2-7,10,and 11)showed antibacterial activity against Staphylococcus aureus and Staphylococcus epidermidis with MIC values of 8-32 μmol/*** findings suggested that meroterpenoids isolated from Psidium guajava can be considered as potential antibacterial leading compounds for pharmaceutical industry.

关键词： Psidium guajava Meroterpenoids x-ray crystal structure Structural elucidation Antibacterial activity