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141.
《结构化学》2010,29(4):660-660
<正>《结构化学》是由中国科学院主管,中国化学会、中国科学院福建物质结构研究所主办的学术性期刊。1982年由我国著名化学家卢嘉锡院士创办并担任主编,现任主编是著名化学家吴新涛院士。《结构化学》主要报道晶体学,量子化学,药物、材料和催化剂等领域物质性  相似文献   
142.
Synthesis and Crystal Structure of 2-Fluoro-4-methyl-3-oxo-4-aza-5α-androst-1-ene-17β-carboxylic Acid Methyl EsterAuthorJANG Yin-Zhi XIANG Zuo LIANG Da-Wei (Department of Applied Chemistry, Zhejiang Sci-Tech. University, Hangzhou 310018, China)AbstractThe title compound VII, 2-fluoro-4-methyl-3-oxo-4-aza-5α-androst-1-ene-17β-carboxylic acid methyl ester (C21H30FNO3, Mr = 363.46), was prepared through a seven-step reaction from pregnenolone, and characterized by elemental and single-crystal X-ray diffraction analyses as well as IR, MS and 1H-NMR spectra. It is of monoclinic system, space group P21/c with a = 6.3882(7), b = 9.9033(11), c = 15.4925(17) , β = 91.923(2)°, V = 979.57(19) 3, Z = 2, Dc = 1.232 mg/m3, μ = 0.088 mm-1, F(000)= 392, R = 0.0465, wR = 0.0989 and λ(MoKα) = 0.71073 . The structure indicates that the four cycles (A: C(1)-C(2)-C(3)-N(1)-C(5)-C(10), B: C(5)-C(6)-C(7)- C(8)-C(9)-C(10), C: C(8)-C(14)-C(13)-C(12)-C(11)-C(9), D: C(14)-C(15)-C(16)-C(17)-C(13)) are in chairand trans-configurations. The results of crystal structure determination show that there exist weak intra-molecular hydrogen bonds, resulting in a two-dimensional supramolecular frame-work of the title compound.Keywordsfluoro-sterol, synthesis, crystal structure, supramolecule  相似文献   
143.
The title compound,(Z)-methyl-3-methoxy-2-{2-[(4-(E-3-p-tolylacryloyl)phenoxy)-methyl]phenyl}acrylate,was synthesized and determined by X-ray single-crystal diffraction. The crystal belongs to the triclinic system,space group P1 with a = 8.0157(8),b = 12.5748(13),c = 13.3768(14) ,α = 64.770(2),β = 75.720 (2),γ = 89.784(2)°,μ = 0.085 mm-1,Mr = 442.49,V = 1174.1(2) 3,Z = 2,Dc = 1.252 g/cm3,F(000) = 468,T = 294(2) K,R = 0.0603 and wR = 0.1498 for 2644 observed reflections with I 2σ(I). X-ray diffraction analysis reveals that the single crystal contains strong non-classical hydrogen bonds. The preliminary bioassay showed that the title compound exhibits inhibitory activity against the Pseudoperoniospora cubensis and Rhizoctonia solani at the test concentration of 200 mg/L.  相似文献   
144.
The title compound,C 12 N 2 O 4 H 14 (M r=250.3),crystallizes in triclinic P1 space group with a=7.7709(9),b=8.7534(11),c=9.6958(12),α=77.103(2),β=80.496(2),γ=86.726(2)o,V=633.9(1) 3,Z=2,F(000)=264,D c=1.311 Mg/m 3,μ(MoKα)=0.1 mm-1,the final R=0.056,and wR=0.15 for 2239 observed reflections (I > 2σ(Ⅰ)).The molecules in the crystal are linked through O-H···O type of hydrogen bonding interaction forming an infinite chainlike structure.The phenylhydrazone ring and oxobutanoate groups are almost planar.The keto hydrazo group adopts a Z-configuration in the molecule and the torsion angle is-177.6(2)°.  相似文献   
145.
正《化学分析计量》由中国兵器工业集团第五三研究所主办,是全国性分析测试、化学计量专业技术刊物,中国科技核心期刊,中国学术期刊综合评价数据库统计源期刊,中国仪器仪表学会分析仪器分会会刊,中国石油和化工行业优秀期刊,中国兵器工业优秀期刊,华东地区优秀期刊,入选美国CA千种表。国内统一刊号:CN 37-1315/O6,国际标准刊号:ISSN 1008-6145。双月刊,大16开本。单月20日出版。  相似文献   
146.
The title molecule, 3-(4-(dimethylamino)benzylidene)-l,5-dioxaspiro[5.5] unde- cane-2,4-dione (I), was synthesized and characterized by elemental analysis, IR, UV-vis spectra and X-ray diffraction analysis. The compound belongs to the triclinic system, space group Pi with a = 6.3640(6), b = 7.7404(8), c = 16.2890(18) A, α = 86.860(2), β = 85.837(2), γ = 79.6720(10)°, V = 786.60(14) A3, D, = 1.331 g/cm3, and F(000) = 336. Geometrical structure of the title compound was optimized by density functional theory (DFT) using B3LYP method with 6-31G** as the basis set. The vibrational frequencies were calculated by the DFT method and the results are consistent with the observed frequencies. The electronic absorption spectra were studied with the time- dependent density functional theory (TD-DFT), showing the calculation results in good agreement with the corresponding experimental data.  相似文献   
147.
The title compound, CsH12NO4"2(H20) 1, was obtained by slow diffusion of cop- per sulfate solution into the solution of 1,4-N,N-bis[tri(hydroxy)methyl]terephthaldiamide in DMSO and characterized by elemental analysis and infrared spectra. The crystal of 1 crystallizes in the monoclinic space group P2Jc with a = 12.943(7), b = 6.446(3), c = 14.157(5) A, fl = 119.76(3), V = 1025.4(9)/3, Z = 2, C16H32N2OI2, Mr= 444.44, Dc= 1.439 g/cm3, F(000) = 476 and/(MoKa) = 0.123 mm"1. The final R = 0.0484 and wR = 0.1080 for 1776 observed reflections with 1〉 2r(/) and R = 0.0679 and wR = 0.1183 for all data. X-ray diffraction reveals that the (2D+ID) hydrogen bonds pillar the structure into an open 3D supramolecular framework with a pore along the b axis (approximate dimensions 5.9*10.5 /2), which is occupied by free water molecules. Photolu- minescent investigation reveals that the title compound displays an emission in the blue region.  相似文献   
148.
The title compounds, C12HIoN307SCI (I) and C15H27NO3S (II), crystallize in the monoclinic system, space group P21/c with a = 7.3995(1), b = 27.8489(6), c = 9.8246(2)/, fl = 131.349(1), V = 1519.82(5) A3, Z = 4, F(000) = 768, Rint = 0.033 and S = 1.03 for I, and in the orthorhombic system, space group Pbca with a = 8.6227(1), b = 16.1480(4), c = 23.8774(6)/, V= 3324.67(12) A3, Z = 8, F(000) = 1312, Rint = 0.024 and S = 1.04 for II. We have devised a convenient procedure for the synthesis of fused organic salts resulting from 1:1 proton-transfer, using an amine and a derivative ofbenzenesulfonic acid. The synthesized salts have a number of applications ranging from their consumption as eco-friendly solvents and catalysts in organic syntheses, to being used as efficient precursors for the production of sulfa drugs. Structures of compounds 3-chloroanilinium 2,4-dinitrobenzenesulfonate (CA-DNBS) and triethylaminium 2,4,6-trimethylbenzenesulfonate (TEA-TMBS) were determined by single-crystal X-ray diffraction studies and infrared spectroscopy.  相似文献   
149.
李正义  来源  石嵩  韩辰  陈亮  孙小强 《结构化学》2013,(9):1387-1391
The title compound 5,17-diformyl-11,23-di(tert-butyl)-25,26,27,28-tetrapropoxycalix[4]arene has been synthesized by selective formylation of 5,11,17,23-tetra(tert-butyl)25,26,27,28-tetrahydroxycalix[4]arene in three steps and characterized by1H NMR and X-ray single-crystal diffraction.The crystal belongs to the monoclinic system,space group C2/c with a = 25.760(3),b = 10.9952(10),c = 18.630(2),β = 119.985(4)°,V = 4570.4(9)3,Z = 4,Dc = 1.106 g/cm3,Mr = 761.01,F(000) = 1648,μ = 0.071 mm-1,MoKa radiation(λ = 0.71073),R = 0.0710 and wR = 0.2411 for 3234 observed reflections with I 2σ(I).X-ray analysis reveals that the title compound adopts a pinched cone conformation which leads to an open cavity.Intermolecular C–H O weak interactions link the molecules along the bc plane,which are effective in the stabilization of the crystal structure.  相似文献   
150.
The title complex bis(2-acetylpyridine thiosemicarbazonato)-indium(iii) perchlo-rate hydrate has been synthesized by the reaction of 2-acetylpyridine thiosemicarbazide(L) with indium(iii) perchlorate,and its structure was characterized by elemental analysis,IR and single-crystal X-ray diffraction.The crystal of the title compound([In(C8H9N4S)2]ClO4·H2O) belongs to monoclinic,space group P21/c with a = 12.6438(18),b = 12.6259(18),c = 15.116(2) nm,β = 105.800(2)°,Z = 4,V = 2321.9(6) nm3,Mr = 618.79,Dc = 1.770 g/cm3,μ = 1.359 mm-1,F(000) = 1240,R = 0.0265 and wR = 0.0675.X-ray analysis indicates that various intriguing hydrogen patterns involving both the solvent intermedia and polyatomic counterions play crucial roles in the self-assembly of functional supramolecules.  相似文献   
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