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《结构化学》1987,(2)
<正> The structure of the title compound has been determined by X-ray analysis. The crystals of this coiapound are monoclinic, space group P21/c with a=8.432(1),b=11.735(3),c=18.254(4)A,β=93.25(2)°,Z=4, and Dx=1.33 g/cm3. The final refinement converged with R=0.031 and Rw=0.031 for 1788 observed independent reflections. 相似文献
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自七十年代以来合成了一系列的二价稀土三元卤化物,目的在于发现新的化合物及寻找稳定低价态的配体.但对更易吸水、氧化的二阶稀土三元碘化物系统的研究,最近几年才开始进行.通过相图及直接合成已获得一系列的碘化物,发展了二价稀士三元卤化物化学,但这方面的合成、结构及其性质的研究仅仅是开始.SmI_2-CsI 体系相图的研究指出,在室温存在一些化合物.本文报导采用一步法合成固液同组成化合物CsSmI_3及固液异组成化合物CsSm_2I_5,通过与相图制备法合成的结果比较,以及其它性质的研究,进一步验证了一步法合成的可靠性和优越性. 相似文献
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(Z)-3-丁烯基苯酞和它的衍生物广泛地存在于微形科植物,如当归、川芎等,这些植物有些是重要的中药材。(Z)-3-丁烯基-4,5-二羟基苯酞是(Z)-3-丁烯基苯酞的类似物;它对前列腺素F2α具有抑制作用。本文以3,4-二甲氧基苯甲醇(2)或价廉易得的胡椒醇(6)为起始原料,分别经四步反应顺利地合成了(Z)-3-丁烯基-4,5羟基苯酞(1)。和一步是本方法的关键,即利用杂原子诱导的区域选择性的芳环 相似文献
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ZENG Xiang-Chao② GU Jian XU Shi-Hai LIU Po-Run 《结构化学》2006,25(2):153-158
1 INTRODUCTION Pyrrole and its derivatives have attracted much attention due to their chemical properties as well as biological activities[1]. They have been widely used as the materials to produce pharmaceutical, essences, biochemicals, etc. It has been found that a great deal of pyrrole derivatives present bioactivities, such as antitumor and antiviral activities[2~5]. Thus, due to the interest in exploring the syntheses of potential bioactive materials which contain pyrrole ring andna… 相似文献
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G. Yu. Ishmuratov M. P. Yakovleva A. V. Galyautdinova L. V. Faifer R. Ya. Kharisov V. V. Zorin G. A. Tolstikov 《Chemistry of Natural Compounds》2001,37(5):486-489
A universal approach to the synthesis of juvenoid hydroprene and methoprene was developed on the basis of monoalkylation of acetoacetate by 1-acetoxy-5-bromo-3-methylpentane, the product of acidic decyclization of 4-methyltetrahydropyran. 相似文献
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磺酰脲类除草剂具有用量低,活性高、选择性好、毒性小的优点。为开发和应用此类除草剂,我们合成了在氮原子上连正丁基的8个新的衍生物,并进行了室内药效测定。 相似文献
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2-苯甲酰基亚甲基-3-三苯胂叉琥珀酸二甲酯(5)是苯甲酰基亚甲基三苯胂与丁炔二羧酸二甲酯在无水 THF 中的加成产物。其晶体和分子结构用 X 射线衍射方法测得。晶体黄色,属三斜晶系,空问群为 PI,晶胞参数:a=0.093(2),b=10.668(2),c=13.547(2)(?),α=92.86(1),β=103.49(1),γ=106.30(1)°,Ζ=2。用四圆衍射仪收集得独立可观察衍射3548个。用直接法解出结构,全矩阵块最小二乘法修正,最终偏离因子R=0.046。该分子中 As-C(19)(亚甲基碳)键长为1.877(?),C(19)-C(20)键长为1.409(?),C(19)-C(29)键长为1.447(?),表明形成了分叉的共轭体系。 相似文献
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采用生物活性基团拼接的分子设计方法, 将活性基团2-氧吡咯烷引入到2H-[1,4]苯并噁嗪-3(4H)-酮分子结构的苯环上, 设计并合成了16个未见文献报道的N-取代-6-(3-氯-4-氯甲基-2-氧吡咯烷-1-基)-7-氟-3,4-二氢-2H-1,4-苯并噁嗪-3-酮衍生物6a~6p, 其结构经IR, 1H NMR, LC/MS和元素分析确证. 初步的生物活性测试结果表明, 部分化合物具有较高的除草和杀虫活性, 如6c~6f等化合物在用量为150 g/hm2时对苘麻(Abutilon theophrasti)、刺苋(Amaranthus spinosus)和藜(Chenopodium album L)等阔叶杂草具有90%以上的抑制率, 6l和6o在500 mg/L浓度下对蚕豆蚜(Aphis fabae)具有90%以上的致死率, 个别化合物还兼具除草及杀虫活性. 相似文献
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Wayda最近报道,无水氯化稀土LnCl_3和叔丁基环戊二烯钠(t-BuCp)Na进行交换反应时,由于歧化反应得不到单取代或双取代的轻稀土氯化物衍生物,只能得到中稀土和重稀土氯化物衍生物,并且没有测得这些配合物的晶体结构。我们采用提高反应温度和延长反应时间,使交换反应进行完全,有效地避免了歧化反应的发生,成功地分离到了单取代或双取代的叔丁基环戊二烯基轻稀土氯化物。并测得(t-BuCp)_2LnCl·nTHF(Ln=Pr,n=2;Ln=Yb,n=1) 相似文献
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M. A. Salama L. A. Almotabacani 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):305-319
4,5-Diaryl-2,3-dihydro-2-mercaptoimidazoles (2a–e) were synthesized. They reacted with chloroacetic acid in gl. acetic acid/Ac 2 O in presence of anhyd. sodium acetate afforded 5,6-diaryl-2,3-dihydro-imidazo[2,1-b]thiazol-3-ones (3a–d). Also these compounds were prepared by the action of chloroacetyl chloride on compounds (2) in pyridine. Compounds (3a–d) on condensation with aromatic aldehydes yield 2-arylmethylene-5,6-diaryl-2,3-dihydroimidazo[2,1-b]-thiazol-3-ones (4a–q). The latter compounds were prepared directly by the reaction of (2) with chloroacetic acid and the aromatic aldehydes. Compounds (3a–d) coupled with aryldiazonium salts in pyridine to give 2-arylhydrazono-5,6-diaryl-2,3-dihydroimidazo[2,1-b]thiazol-3-ones (5a–r). Also compounds (2) when reacted with 2 or 3-bromopropionic acid afford 2,3-di-hydro-5,6-diaryl-2-methylimidazo[2,1-b]thiazol-3-ones (6a–d) and 2,3-di-hydro-6,7-diaryl imidazo-[2,1-b]-1,3-thiazin-4-ones (7a–d), respectively. Compounds (3, 6, and 7) have been cleaved by aromatic amines to give the corresponding 2-(4′,5′-diaryl-2′,3′-dihydroimidazol-2′-yl)thioacetanilide (8a–f), 2-(2′,3′-dihydro-4′,5′-diaryl imidazol-2′-yl)thiopropionamide (9a–c), and 3-(2′,3′-dihydro-4′,5′-diaryl-imidazol-2′-yl)thiopropionamide (10a–d) respectively. All the prepared compounds show considerable antimicrobial activity against bacteria, yeast, and fungi. 相似文献
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K对Mn—Co—O的结构及氧化活性的影响 总被引:1,自引:0,他引:1
利用XRD,TPD,TFD-MS及催化氧化反应等实验技术,研究了K对Mn-Co-O的结构及氧化活性的影响。XRD结果表明,Mn-Co-O系已形成反尖晶石型的MnCo_2O_4结构;K-Mn-Co-O系中除MnCo_2O_4型结构外,还有新相KMnO_2存在。根据O_2的TPD-MS及吡啶的TPD结果,Mn-Co-O中添加适量的K能提高供氧活性和增加供氧数目,但酸中心数目减少,强度降低。K对Mn-Co—O催化剂氧化活性的影响随反应物分子结构的不同而异,对乙酸乙脂、苯甲酰氯等极性有机物的完全氧化反应,K能提高氧化活性,但对苯、正己烷等非极性有机物的完全氧化反应,K使其活性降低。 相似文献
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Krzysztof Kostka Roman Modranka 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):279-285
Abstract Chromone-2- and chromone-3-hydroxymethanephosphonic- as well as chromone-2- and chromone-3-methanephosphonic acids and esters were synthesized. 相似文献
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SincethesynthesisandherbicidalactivityofDPX-4l89wasreportedinl98o,awidevarietyofsulfonylureaswithimprovedselectivityand/oreffectivenesshavebeendeveloped'-'.Inacontinuingstudyonthesynthesisandherbicidalactivityofthiophenesulfonylureaandsubstitutedbenzenesulfonylureaderivatives'-',wehavefoundthatsulfonylureaherbicideshaveexcellentherbicidalactivityagainstawiderangeofweeds,butmostofthemwerenotselectivelyactiveherbicides.Inthispaperwedescribethesynthesisandherbicidalactivityofthirteen3-benzoly-l-… 相似文献
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本文介绍利用一步法反应,分别合成出新的Fe_3S_3原子簇化合物[Et_4N]_3[Fe_3(p-CH_3PhS)_3Cl_3Br_3](1)和[Et_4N]_3[Fe_3(P-CH_3PhS)_3Cl_6](2)。X射线晶体结构测定表明,化合物1和2的阴离子骨架均为3Fe、3S交叉排列的六无环,略呈船型结构。1和2均属三斜晶系,空间群均为P1。1的晶胞参数:a= 12.301(2),b=13.780(4),c=19.097(2)A,α=101.39(2),β=101.92(1),γ=196.15(2)°,Z=2.2的晶胞参数:a=12.226(4),b=15.323(3),c=17.012(2)A,α=70·72(1),β=88.65(5),γ=72.51(2)°,Z=2。本文还讨论了该反应的立体化学和机理。 相似文献