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81.
The title compound, 2,6-bis(benzimidazo(1,2-c)quinazolin-6-yl)pyridine tetrahydrate, was synthesized by simple condensation of 2-(2-sminophenyl) benzimidazole with pyfidine- 2,6-dicarboxylic acid and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group C2/c with a = 22.226(8), b = 16.730(7), c = 16.820(5)A, β = 115.796(13)°, V = 5631(4)A^3, C33H27NTO4, Mr = 585.62, Z = 8, Dc = 1.381 g/cm^3, λ(MoKα) = 0.71073 A, F(000) = 2448 and μ = 0.09 mm^-1. The structure was refined to the final R = 0.0730 and wR = 0.1573 for 6346 independent reflections (Rint = 0.0801) and 3384 observed reflections (I 〉 2σ(I)). In the crystal, the molecules are linked through intermolecular O-H…O and O-H…N hydrogen bonds. Intermolecular π-π interactions (with distances of about 3.45 A) are pronounced in the crystal structure.  相似文献   
82.
The title compound, N,N'-bis-[3-chloro-5-S-(l-menthyloxy)-2(5H)-4-furanon-yl]- propane-l,3-diamine (C31H48Cl2N2O6, Mr = 615.61), has been synthesized and characterized by IR, 1H NMR, MS, elemental analysis and single-crystal X-ray diffraction. The crystal crystallizes in the monoclinic system, space group C2 with a = 16.1091(4), b = 11.1880(3), c = 19.2854(5) A, β = 106.297(2)°, V = 3336.12(15) A3, Z = 4, Dc = 1.226 mg/m3,μ = 0.237 mm^-1, F(000) = 1320, the final R = 0.0531 and wR = 0.0700 for 2760 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the title compound possesses four rings: two chiral five-membered furanone rings and two six-membered cyclohexane rings with chair conformation, containing eight chiral centers: C2(S), C3(R), C5(R), C10(S), C18(S), C21(R), C22(S) and C25(R). The structure is stabilized by N-H…O hydrogen bonding interaction.  相似文献   
83.
A novel ionic compound [Fe(CN)6·(PhCHeNC9H7)4]·12H2O
(C70H80FeN10O12, Mr = 1309.29) has been synthesized and its structure was characterized by I-R, elemental analysis and X-ray diffraction. The compound crystaUizes in triclinic, space group P1, with a = 10.968(7), b = 11.466(7), c = 14.077(8)A, α= 87.014(7), β= 78.124(7), γ = 72.708(7)°, V = 1654.1(17)A3, Z = 1, Dc = 1.314 g·cm^-3, F(000) = 692, p = 0.298 mm^-1, the final R = 0.0519 and wR = 0.1355. The building unit of the title compound consists of four (PhCH2N+C9H7) ions, one [Fe(CN)6]4- anion, and a dozen water molecules. According to the structural analysis, [Fe(CN)6]4- ions are linked together by O-H…O and O-H…N hydrogen bonds, while (PhCH2N+C9HT) and [Fe(CN)6]4- ions interact with each other by electrostatic force to form an ionic compound.  相似文献   
84.
The title compound 10-(4,5-dibenzylthio-1,3-dithiol-2-ylidene)anthracen-9(10H)- one (C31H22OS4) has been synthesized, and its crystal structure was prepared by crystallization from CH2Cl2-MeOH. The crystal belongs to the triclinic system, space group Pi with a = 10.9758(3), b = 11.4241(4), c = 11.7460(2)A^°, α = 62.379(2), β = 81.227(3), γ = 80.321(2)°, Mr = 538.73, V = 1281.69(7) A^°^3, Z = 2, Dc = 1.396 g/cm^3, F(000) = 560,μ = 0.395 mm^-1, the final R = 0.0291 and wR = 0.0739. The molecular structure is severely distorted from planarity. The central ring of anthraquinone moiety adopts a boat conformation, while the two outer benzene rings are tilted in the opposite direction to form a dihedral angle of 23.65°. The photocurrent generation was measured and an anodic photocurrent response was obtained. The electronic spectrum was studied by using TDDFr method on the basis of optimized geometries with B3LYP method. The obtained results are in good agreement with the experimental values.  相似文献   
85.
正本刊是宁波大学主办的综合性自然科学和工程技术学术期刊,创刊于1988年,现为季刊,国内外公开发行,主要刊登理、工、农、林、医等学科的学术论文和研究成果,欢迎各方学人来稿.1投稿要求1.1文稿书写要求:文章论点明确、论据充分、层次分明,文字简练,图表清晰,篇幅(含图表)一般不超过6000字.1.2文稿书写顺序:中文标题;作者姓名;作者单位;中文摘要(要有目的、方法、结果、结论 4要素内容,200字左右);中文关键词(3~5个,用分号隔开);中图分类号(按《中国图书馆分类法》(第4版)标引);正文;附录(非必有);参考文  相似文献   
86.
87.
勘误声明     
根据作者要求,对下述论文进行勘误:出版信息:2020年38卷第2期,页码为286~290论文标题:急性脑梗死患者心电图特征与病情分型及其预后状况的关系作者:郭小云,王金桃DOI:10.7517/issn.1674-0475.190911勘误内容:1.作者单位由“山西医科大学附属医院”更正为“山西医科大学”2.文章中的“本院”更正为“吕梁市人民医院”特此告知并诚挚地向读者致歉!  相似文献   
88.
The title compound 4-(N,N-diphenylamino)styrene-4'-N-methylpyridinium iodine (abbreviated to PASMPI) was synthesized by a facile condensation reaction with a high yield. The red crystal including a mol...  相似文献   
89.
90.
LI  Zong-Xiao ZHANG  Xin-Li PU  Xiao-Hua 《结构化学》2010,29(12):1824-1827
The title compound,2,6-bis(2-pyridinylmethyl)-3,5-bis(2-hydroxyl-5-chlorophe nyl)-pyrazine(C26H12Cl2N4O2C2H8O2,Mr=551.41),has been synthesized and characterized by LC-ESIMS,NMR,UV and IR spectroscopy as well as by X-ray single-crystal diffraction.The compound behaves as a substituted pyrazine.The hydrogen atoms on C(2) and C(3) are substituted by 2-pyridinyl,whereas those on C(1) and C(4) are substituted by 2-hydroxyl-5-chlorophenyl.It crystallizes in the monoclinic system,space group P21/c with a=8.9433(12),b=32.003(4),c=10.5209(18),β=111.199(2)°,V=2807.5(7)3,Z=4,Dc=1.305 mg/m3,F(000)=1144 and μ=0.094 mm-1.A total of 13235 reflections were collected in the range of 2.17~25.01o by using a phi and omega scan mode,of which 4923 were unique(Rint=0.0692) and 2872 observed reflections with Ⅰ > 2σ(Ⅰ) were used in the structure solution and refinement.  相似文献   
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