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1.
反式9, 10-二氢-9, 10-二苯基-9, 10-菲二醇包结性能的研究   总被引:5,自引:0,他引:5  
合成了一种具有螯形结构的反式-9, 10-二氢-9, 10-二苯基-9,10-菲二醇(1)作为主体分子。它能与许多有机小分子化合物, 诸如DMF, DMSO, 吡啶, 哌啶, 喹啉, 异喹啉等形成包结化合物。本文还报道了这些包结化合物的IR, 粉末XRD的表征, 用^1H NMR谱测定了它们的分子摩尔比。DMF包结物的单晶四圆X衍射结果表明主体分子1与客体分子形成的包结物为配位笼状包合物。  相似文献   

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When treated with a series of nucleophiles cis-3-cyanomethylene-3-deocy-1,2:5,6-di-O-isopropylidene-α-D-ribo-hexofurannose ( 1 ) may yield its trans isomer, a product of allylic isomerization or a product of conjugate addition, depending on the nature of the nucleophile. The configuration of the starting material is also important as shown by the differences in reactivity between 1 and its trans-xylo isomer 8 .  相似文献   

5.
以PCl3和季戊四醇为原料合成了中间体3,9$C二氯-2,4,8,10$C四氧代-3,9-二磷杂螺[5.5]十一烷,产率达99.6%.对反应条件进行了优化,最佳反应条件为:PCl3和季戊四醇摩尔比为2.5∶1,反应温度80℃,反应时间1.5h.  相似文献   

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A two-dimensional (2D) gas chromatography/electron impact-mass spectrometry (GC/EI-MS) method for simultaneous quantification of Delta(9)-tetrahydrocannabinol (THC), 11-hydroxy-Delta(9)-tetrahydrocannabinol (11-OH-THC), and 11-nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid (THCCOOH) in human plasma was developed and validated. The method employs 2D capillary GC and cryofocusing for enhanced resolution and sensitivity. THC, 11-OH-THC, and THCCOOH were extracted by precipitation with acetonitrile followed by solid-phase extraction. GC separation of trimethylsilyl derivatives of analytes was accomplished with two capillary columns in series coupled via a pneumatic Deans switch system. Detection and quantification were accomplished with a bench-top single quadrupole mass spectrometer operated in electron impact-selected ion monitoring mode. Limits of quantification (LOQ) were 0.125, 0.25 and 0.125 ng/mL for THC, 11-OH-THC, and THCCOOH, respectively. Accuracy ranged from 86.0 to 113.0% for all analytes. Intra- and inter-assay precision, as percent relative standard deviation, was less than 14.1% for THC, 11-OH-THC, and THCCOOH. The method was successfully applied to quantification of THC and its 11-OH-THC and THCCOOH metabolites in plasma specimens following controlled administration of THC.  相似文献   

8.
We herein descirbe various methods for synthesizing 1-foryml-2-hydroxyanthracene, 2-formyl-1-hydroxyanthracene and 1-formyl-2-hydroxy 6-methoxyanthracene. These compounds are used as starting materials to prepare anthrafuran derivates nitracted on their heterocycles in order to copare their mutagenic properties to that of the corresponding nitro-derivates of naphthofurans.  相似文献   

9.
The authors describe the synthesis of decahydro-4-quinolinones and N-substituted 4-alkynyl-, 4-allyl- and 4-alkyldecahydro-4-quinolinols and discuss the stereochemical problems of this compounds.  相似文献   

10.
The retention indices for cycloalkanes, cycloalkenes and bicyclic compounds have been measured as a function of temperature for different liquids phases. The diastereomeric bicycloalkenyl-2 were separated. Some rules concerning the indices are given.  相似文献   

11.
The synthesis, crystal structures, second-harmonic generation (SHG), piezoelectric, pyroelectric, and ferroelectric properties of three polar noncentrosymmetric (NCS) hexagonal tungsten bronze-type oxides are reported. The materials KNbW 2O 9, RbNbW 2O 9, and KTaW 2O 9 were synthesized by standard solid-state techniques and structurally characterized by laboratory powder X-ray diffraction. The compounds are isostructural, crystallizing in the polar NCS space group Cmm2. The materials exhibit a corner-shared MO 6 (M = Nb (5+)/W (6+) or Ta (5+)/W (6+)) octahedral framework, with K (+) or Rb (+) occupying the "hexagonal" tunnels. The d (0) transition metals, Nb (5+), Ta (5+), and W (6+), are displaced from the center of their oxide octahedra attributable to second-order Jahn-Teller effects. SHG measurements using 1064 nm radiation revealed frequency-doubling efficiencies ranging from 180 to 220 x alpha-SiO 2. Converse piezoelectric measurements resulted in d 33 values ranging from 10 to 41 pm V (-1). The total pyroelectric coefficient, p, at 50 degrees C ranged from -6.5 to -34.5 muC K (-1) m (-2). The reported materials are also ferroelectric, as demonstrated by hysteresis loops (polarization vs electric field). Spontaneous polarization values, P s, ranging from 2.1 to 8.4 muC cm (-2) were measured. The magnitudes of the SHG efficiency, piezoelectric response, pyroelectric coefficient, and ferroelectric polarization are strongly dependent on the out-of-center distortion of the d (0) transition metals. Structure-property relationships are discussed and explored. Crystal data: KNbW 2O 9, orthorhombic, space group Cmm2 (No. 35), a = 21.9554(2) A, b = 12.60725(15) A, c = 3.87748(3) A, V = 1073.273(13) A (3), and Z = 6; RbNbW 2O 9, orthorhombic, space group Cmm2 (No. 35), a = 22.00985(12) A, b = 12.66916(7) A, c = 3.8989(2) A, V = 1086.182(10) A (3), and Z = 6; KTaW 2O 9, orthorhombic, space group Cmm2 (No. 35), a = 22.0025(2) A, b = 12.68532(14) A, c = 3.84456(4) A, V = 1073.05(2) A (3), and Z = 6.  相似文献   

12.
1-Alkyl-2-(N-methylidenealkylamino)aziridines are obtained by the reaction of primary amines with either α-chloroacraldehyde or α-chlorocrotonaldehyde. Structural assignments are made by nmr spectroscopy. The thermal rearrangement of 1-alkyl-2-(N-methylidenealkylamino)-3-methylaziridines to pyrroles is described.  相似文献   

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Ugrinov A  Sevov SC 《Inorganic chemistry》2003,42(19):5789-5791
A tetramer of nine-atom deltahedral germanium clusters and charge 8-, [Ge9=Ge9=Ge9=Ge9]8- , has been characterized as a (Rb-18C6)(+) salt (18C6 = 18-crown-6 polyether). The clusters are connected by pairs of parallel bonds, and the electrons are delocalized over the whole anion. The size of the tetramer is of nanorod dimensions, ca. 2 nm.  相似文献   

15.
The equilibrium NH acidities of acridan, phenanthridone, 9-acridone, and 2-substituted 9-acridones (substituents: Me2N, MeO, F, Br, I, and NO2) were measured by transmetallation in dimethyl sulfoxide (DMSO). The role of conjugation and the aromatic character of the heterocyclic ring in stabilization of the anions is discussed. The energies of deprotonation of phenanthridone and 9-acridone were estimated by the CNDO/2 (complete neglect of differential overlap) method; it is shown that the difference between them is in agreement with the experimental results. The dependence pK = 16.2 – 3.37I – 1.84R (s 0.23, r 0.989) was obtained for the 2-substituted 9-acridones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1241–1244, September, 1982.We thank É. S. Shcherbakova for her assistance in the correlation analysis of the data on the acidities of the substituted 9-acridones.  相似文献   

16.
Anionic polymerizations of methylmethacrylate, initiated by fluorenyl-alkali metals in ether media or in hexamethyl phosphotriamide, give syndiotactic polymers. Calculated differential entropies and enthalpies of activation between the iso- and syndiotactic placements reveal that in dioxane, tetrahydropyrane and tetrahydrofurane the syndiotacticity increases from K+ to Li+. With solvents having higher dielectric constant (such as hexamethyl phosphotriamide) or higher donating power (such as glyme 4), the tacticity of the polymers is not affected by the nature of the counter-ions.

It has been suggested that, with dioxane, tetrahydropyrane and tetrahydrofurane, the donating power is not strong enough to destroy the coordination bonds between the C=O groups of the living polymer chains and the counter-ions.  相似文献   


17.
The stability constants of N-acetylgycinates of some rare earths in aqueous solution have been determined by a potentiometric method, and by a solvent extraction technique. The ligand forms 1:1 complexes which are stabilized by relatively large positive entropies of formation, the corresponding enthalpies being endothermic. This backs up the assumption that a conjugate base of an amino acid forms innersphere complexes and acts as a unidentate ligand towards a rare earth cation, like a simple carboxylate.  相似文献   

18.
Paramagnetic complexes of 9, 10-anthraquinone and 9-fluorenone adsorbed on the surface of calcium, magnesium, zinc, zirconium, and aluminum oxides and modified Al2O3 as well as on mixed oxides were studied by ESR and electron-nuclear double resonance. Radical anions that do not interact with Lewis acid sites are generated on the surfaces of oxides with electrondonating properties (CaO, MgO). Paramagnetic complexes of the anthraquinone or fluorenone radical anion with Lewis acid sites (coordinatively unsaturated metal cations) are formed in other cases. Several types of similar complexes can be formed. Mechanisms of interaction of the probe molecules with the metal oxide surface were proposed.  相似文献   

19.
Reactions of Mononucleophiles with a Bromoenurononitrile, Precursor and Partial Synthetic Equivalent of an Ynurononitrile Several mononucleophiles (bases) have been reacted with one or the other of the geometrical isomers of the bromoenurononitrile 1. Depending on the nucleophile and the conditions, many different mechanistic pathways were followed, f. ex.: with OH?, stereospecific elimination from (Z)- 1 leading to 2 , with N?3 and F?, stereospecific E-AN reactions leading from (Z)- 1 to (Z)- 8 and (Z)- 12 respectively, with PhCH2SH, conjugate nucleophilic addition to 7, with Me2NH, conjugate nucleophilic addition followed by a SN2 to 11 , as well as several cases of nonstereoselective, probably AN-E, reactions leading to 3,6,9 and 10. In spite of their diversified reactivity, bromoenurononitriles like 1 , partial synthetic equivalent of 2 , constitute useful synthetic intermediates.  相似文献   

20.
The title compound 9 S,9 aS-neotuberostemonine(1) was isolated from the 95% ethanol extract of the roots of Stemona tuberosa. The crystal structure of 1, C_922)H_(33)NO_4, was determined by single-crystal X-ray diffraction analysis. The crystal belongs to orthorhombic system, space group P212121, with a = 9.0115(11), b = 10.612(4), c = 22.074(3) ?, V = 2110.9(8) ?~3, Z = 4, Mr = 375.49, Dc = 1.182 g/cm3, λ= 0.71079 ?, μ = 0.080 cm-1, F(000) = 816, S = 1.019, R = 0.0579 and w R = 0.1358. A total of 3109 unique reflections were collected, of which 2902 were observed(I 2σ(I)). The absolute configuration of 1 could be assigned by referring to the conserved configuration of the methyl groups at C(13) and C(20). In the solid state, the molecules were linked into a chain along the a-axis through weak hydrogen bond C(11)–H(11 A)…O(2). Compound 1 shows significant inhibition of cough by 24%, 44% and 65% at doses of 50, 100 and 150 mg/kg, respectively.  相似文献   

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