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1.
Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis,IR spectra,UV spectra,XRD,TG-DSC;and were compared with Hquin-PW12.The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.  相似文献   

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Ab initio CI studies of the UV-PES of the title compounds are described. The assignments are discussed in relation to through-bond and through-space effects.  相似文献   

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A series of novel bis-squaramidoacid ligands were prepared. Prochiral ketone and diketones were direct reduced by borane in the presence of these ligands giving secondary alcohol products with enantiomeric excesses up to 64.2% for ω-bromoacetophenone and 90.0% for 1,6-diphenyl- 1, 6-hexanedione.  相似文献   

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Low-temperature condensates of water and water-methane mixture are studied in the temperature range of 65–200 K. Amorphous samples are obtained by molecular beam deposition under vacuum conditions on the substrate cooled with liquid nitrogen. The vitrification and crystallization temperatures are determined from the changes in the dielectric properties of the condensates upon heating. The kinetics of crystallization of amorphous water layers is studied by differential thermal analysis. The temperature conditions for the growth of thick methane crystalline hydrate layers during the low-temperature condensation of molecular water-gas mixture beams are found.  相似文献   

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A series of 2-benzyl-1,3-dicabonyl derivatives was synthesized.Their insulin-sensitizing activity was evaluated in 3T3-L1 preadipocyte cells.Compounds3,26 and 27 were found to possess strong insulin-sensitizing activity in vitro and were selected for further hypoglycemic evaluation in vivo.  相似文献   

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李超  罗保生  孙天恩 《结构化学》2001,20(2):100-103
1 INTRODUCTIONCoumarinisonekindofthelactoneofortho hydroxylcassiaacid .Itcomposesalargenumberofcoumaricderivateseriesbecauseofthedifferentpositions,kindsandnumbersofthesubstituentgroupswhichlinkupwiththearomaticandlactonerings[1 ,2 ,3] .Thiskindofcompoundsex…  相似文献   

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Synthesis and Crystal Structure of a β—Lactam Derivative of 2,4—Diary   总被引:1,自引:0,他引:1  
李媛  杜彩云 《结构化学》1999,18(1):57-60
1INTRODUCTION1,5benzothiazepinesposespotentialbiologicalactivities〔1〕.CycloadditionreactionsattheirC=Ndoublebondhavearousedc...  相似文献   

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黄泰山  姚志杨 《结构化学》1995,14(2):113-116
SynthesisandStructureof2-AcetylthiopheneThiosemicarbazone¥HuangTai-Shan;YaoZhi-Yang;ZhouZhao-Hui(DepartmentofChemistry,Xiamen...  相似文献   

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JPC – Journal of Planar Chromatography – Modern TLC - This paper reports an investigation of physicochemical properties of four series of carbamates of 3-hydroxy and...  相似文献   

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INTRODUCTION2-Bromoaldisin was first isolated from the marine sponge Hymeniacidon aldis [1,2]. In the course of our systematic search for bioactive substances from marine organisms, we have studied the marine sponge Phacellia fusca Schmidt and obtained the title compound. Up to now, there is no report on the crystal structure of 2-bromoaldisin. This paper reports the isolation and crystal structure of it. EXPERIMENTALIsolation of 2-bromoaldisinThe sponge, Phacellia fusca Schmidt wa…  相似文献   

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田玉鹏  罗保生 《结构化学》1996,15(4):307-310
SynthesisandStructureof4-NitrobenzaldehydeThiosemicarbazoneTianYu-Peng;DuanChun-Ying;LuZhong-Lin;YouXiao-Zeng(CoordinationChe...  相似文献   

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《European Polymer Journal》1986,22(7):565-567
Polycondensations of 1,2- and 1,4-naphthoquinones with hydrazine hydrate and disulphinylhydrazine under various conditions were carried out. The optimum parameters for the disulphinylhydrazine synthesis were established. The thermal stabilities and electrical conductivities of the polynaphthoquinoneazines were determined.  相似文献   

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1 INTRODUCTION 6-Bromo-piperonal-dimethyl-acetal is an intermediate used for the synthesis of natural products, such as podophyllotoxin[1] and the related compounds[2~6] due to the useful biological activities associated with some of its derivatives[7, 8]. In particular, glycoside derivatives of 4?dimethyl- 4-epipodophyllotoxin have been used in cancer chemotherapy[9, 10]. The title compound has been synthesized from raw material piperonal, after bromo substitution and acetal protection…  相似文献   

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The alkoxides of molybdenum and other heavy transition elements such as Ta or Nb were found to be unreactive towards each other. The bimetallic derivatives could be obtained either via partial hydrolysis that gave Mo2Ta4O8(OMe)16 (I) or via partial thermolysis that provided access to Mo4Ta2O8(OiPr)14 (II), Mo3Ta2O8(OiPr)10 (III), Mo4Ta4O16(OiPr)12 (IV), Mo4Nb2O8(OiPr)14 (V) and Mo4W2–x Mo x O10(OiPr)12 (VI). IVI can be isolated only from hydrocarbon media as the presence of alcohols leads to precipitation of insoluble homometallic derivatives of molybdenum. The cathodic reduction of MoO(OR)4 (R = Me, Et) in the presence of LiCl and M(OR)5 (M = Nb, Ta) leads only to formation of LiMo2O2(OMe)7(MeOH) (VII) or LiMo2O2(OEt)7 (VIII) respectively.  相似文献   

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The polymerization of aniline in the presence of poly(4-styrenesulfonic acid) and poly(2-acryla-mido-2-methyl-1-propanesulfonic acid) results in interpolyelectrolyte complexes with a composition and a dispersion stability depending on the aniline-to-polyanion ratio in the initial reaction mixture. As opposed to polymerization mediated by poly(4-styrenesulfonic acid), the template polymerization of aniline conducted in the presence of poly(2-acrylamido-2-methyl-1-propanesulfonic acid) leads to the structural template effect that manifests itself as the formation of polyaniline containing 1,2- and 1,4-substituted benzene rings. It is found that the electron conductivity of the polyaniline-polyanion interpolyelectrolyte complexes depends not only on the content but also on the nature of the used polyacid and proves to be higher in the case of stoichiometric interpolyelectrolyte complexes formed in the presence of poly(4-styrenesulfonic acid).  相似文献   

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Aryloxy-terminated polydimethylsiloxanes (AOS) were synthesized by the telomerization of hexamethylcyclotrisiloxane(D3) with phenols.The structures of AOS were characterized by UV,IR,^2HNMR and elemental analysis,The effects of the reaction conditions and the mole ratios of the reactants on the molecular weight of the polymer were discussed.AOS′s structural influence on bactericidal action,flocculation and hydrolysis was studied.  相似文献   

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