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1.
Summary New complexes of 2,2-dipyridyl and 4,4-dipyridyl with thulium salts TmX 3 (whereX=Cl, Br, NO 3 , NCS, and ClO 4 ) have been prepared and their solubilities in water at 21 °C were determined. The IR spectra of these compounds are discussed. The conditions of thermal decomposition of the complexes were also studied.
Synthese und Eigenschaften von 2,2-Dipyridyl- und 4,4-Dipyridylkomplexen mit Thuliumsalzen
Zusammenfassung Es wurden neue 2,2-Dipyridyl- und 4,4-Dipyridyl-Komplexen mit Thuliumsalzen TmX 3 (X=Cl, Br No 3 , NCS, ClO 4 ) dargestellt und ihre Wasserlöslihkeit bei 21 °C bestimmt. Die IR-Spektren werden diskutiert. Das thermische Verhalten der erhaltenen Komplexe wurde untersucht.
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2.
Summary A modified synthesis of protected 2,3-dideoxyribose5 starting fromL-glutamic acid (1) is described. Reaction of5 with silylated 5-hydroxymethyluracil7 a and 5-alkoxymethyluracils7 b–e in the presence of trimethylsilyl triflate afforded an anomeric mixture of 2,3-dideoxyuridine derivatives8 a–e and9 a–e. Deprotection with methanolic ammonia and separation by chromatography gave the corresponding nucleosides10 a–e and11 a–e. Treatment of9 b–e with tri(1H-1,2,4-triazol-1-yl)phosphine oxide and subsequent reaction of12 b–e with ammonia in dioxane afforded the cytosine derivatives13 b–e which on treatment with methanolic ammonia gave the corresponding 2,3-dideoxycytidine derivatives14 b–e and15 b–e. In contrast with the parent compounds, these alkoxymethyl derivatives had no appreciable activity against human immunodeficiency virus (HIV-1).
Synthese von 2,3-Dideoxynucleosiden aus 5-Alkoxymethyluracilen
Zusammenfassung Ausgehend vonL-Glutaminsäure (1) wird eine modifizierte Synthese von geschützter 2,3-Dideoxyribose (5) beschrieben. Reaktion von5 mit silyliertem 5-Alkoxymethyluracilen7 b–e in Gegenwart von Trimethylsilyltriflat ergab anomere Mischungen der 2,3-Dideoxyuridinderivate8 a–e und9 a–e. Abspaltung der Schutzgruppe mit methanolischen Ammoniak und chromatographische Trennung ergab die entsprechenden Nucleoside10 a–e und11 a–e. Behandlung von9 b–e mit Tri(1H-1,2,4-triazol-1-yl)phosphinoxid und nachfolgende Reaktion von12 b–e mit Ammoniak in Dioxan ergab die Cytosinderivate13 b–e, welche nach Behandlung mit methanolischem Ammoniak die entsprechenden 2,3-Dideoxycytidinderivate14 b–e und15 b–e ergaben. Im Gegensatz zur Stammverbindung hatten diese Alkoxymethylderivate keine nennenswerte Wirksamkeit gegen den menschlichen Immunschwächevirus (HIV-1).
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3.
The NMR spectral data including high resolution 1H, 13C and 2D NMR for butrin, 3,4,7-trihydroxyflavanone 3,7-di-O--D-glucopyranoside, isolated from flowers of Butea monosperma, are reported here for the first time. Butrin was hydrolyzed using b-glucosidase to butin in high yield. They were subjected to free radical scavenging test using 2,2-diphenyl-1-picrylhydrazyl (DPPH) spectrophotometric assay. At a dose of 4 × 10-8 mol of tested compounds, the percentage of reduced DPPH for butin was 14.5% while no reduction was observed for butrin (0%).  相似文献   

4.
The x-ray structure is solved for a tetrahydrothebaine derivative containing a C7,8-annelated thiolane dioxide fragment, the influence of which on the change of conformation of the morphine skeleton is examined.Institute of Organic Chemistry, Ural Branch, Russian Academy of Sciences, 450054 Ufa. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2565–2572, November, 1992.  相似文献   

5.
An optosensing method for gadolinium based on the room-temperature phosphorescence behavior in aqueous solution induced by the transient adsorption of the complex formed by 1,4-bis (1-phenyl-3-methyl-5-pyrazolone-4-)butanedione (1,4) with Gd (III) on the chelating resin Chelex 100 (packed in a flow cell) is proposed. The proposed optosensing is satisfactory for the determination of the gadolinium ion in the range 8 × 10–7–5 × 10–5 M with a correlation coefficient of 0.995. The relative standard deviation was 2.0% for determination of 5× 10–6 M gadolinium ion (n = 10). The response mechanism of the optosensing and the interferences of other lanthanide ions were also investigated. The method has been used to determine gadolinium ion in synthetic sample.  相似文献   

6.
The process of structurization in solutions of H-complexes of dimethyl 3,3,4,4 -benzophenonetetracarboxylate with 4,4 -diaminodiphenylmethane has been investigated in 90 % aqueous methanol in the concentration range 6 to 0.2 g L–1. Structural instability of the solutions has been found in the concentration range from 1.2 to 2 g L–1. The addition of an ionogenic substance stabilizes the solution and results in monotonic changes in the structural parameters as solution is diluted. A tendency toward variation of the extemum in the mean correlation radius of the polarizability fluctuation has been found in the concentration range 0.6-–1 g L–1, which had been observed previously for polymer systems.For Part 1, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1219–1221, July, 1994.  相似文献   

7.
Mono- and dicarbanionic derivatives of 4,4bis(1-phenylethylene)1,1-biphenyl) (BPB): are prepared by addition of cumyl-barium or polystyryl-barium to BPB in tetrahydrofuran (THF). Spectroscopic and conductimetric measurements on monoadduct solutions were carried out in a temperature range from –105 to 25°C. At low temperature these solutions show a large spectral shift, due to the equilibrium between tight and solvent separated ion pairs. The thermodynamic parameters of this two step ion pair solvation were determined and the corresponding dissociation constant was found to be K d =1×10–6 mol-dm–3 at 20°C. Once the first addition completed, the remaining double bond of the monoadduct seems to be less reactive than those of the original BPB. The diadduct has been prepared in the presence of an excess of cumyl-barium, and characterized spectroscopically.  相似文献   

8.
Intercalation of ,-alkanediamines, NH2(CH2) n NH2 (n = 3–10), into layered aluminium dihydrogen triphosphate dihydrate, AlH2(P3(O10... 2H2O, was investigated by XRD, DTA-TG, elemental analysis, and solid-state 31P, 13C and 27Al NMR. ,-Alkanediamines are intercalated to form a monomolecular layer in the interlayer region, in which the alkanediamines incline at 57 ± 5° to the phosphate layers, whereas n-alkylamines form a bilayer structure with the same inclination angle. Two amino groups in an ,-alkanediamine molecule bridge the layered sheets of phosphates.  相似文献   

9.
Photochromic 1, 3, 3 -trimethyl-6-trifluoromethylsulfonyl-spiro(indoline-2,2-ben-zo[b]pyran) (1) was studied by X-ray diffraction analysis. In compound1, the Cspiro-O bond (1.49(1) Å (average)), broken on photoexcitation, is the longest of all the indoline spiropyrans studied.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1969–1971, November, 1994.  相似文献   

10.
The equilibrium of 1-pentafluorophenylthio-1,2-dimethylacenaphthylenium and 1,2-dimethylacenaphthylene-1, 2-S-pentafluorophenylepisulphonium ions in different media has been investigated by1H and13C NMR spectroscopy using isotope perturbation. It has been found that this equilibrium is weakly sensitive to variation in the medium.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1057–1060, June, 1993.  相似文献   

11.
The condensation of aminals of -dimethylaminoacrolein and 5-dimethylaminopenta-2,4-dienal with cyclic and acyclic 1,2-, 1,3-, 1,4-, 1,5-, and 1,6-diketones was studied. A series of previously unknown bis(,-dimethylaminopolyenyl)diketones was synthesized; their structures were established by means of1H and13C NMR spectroscopies. The electron absorption spectra were employed to study the mutual influence of -aminopolyene chromophores separated by two C=O groups.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1235–1241, July, 1993.  相似文献   

12.
Summary Methyl 3-benzoylthio-5-O-tert-butyldiphenylsilyl-2,3-dideoxy--D-erythro-pentofuranoside (4) and its corresponding anomer5 were synthesized in four steps from 2-deoxy-D-ribose and used as substrates for the synthesis of nucleosides by condensation with silylated thymidine and N6-isobutyryladenine. The nucleosides were deprotected by treatment with Bu4NF inTHF followed by reaction with MeONa in MeOH to give 3-deoxy-3-mercaptothymidine (8), 2,3-dideoxy-3-mercaptoadenosine (15) and its corresponding anomer16. In the latter reactions it was important to use degassed solvents to minimize formation of the corresponding disulfides of purine nucleosides. Using Bu4NF, without subsequent reaction with MeONa in the deprotection reaction, resulted in intermolecular transesterification reactions.On leave from Chemistry Department, Faculties of Science and Education, Tanta University, Tanta, Egypt  相似文献   

13.
The Dinitrone 2,2-diphenyl-3,3-bi-3H-indole-1,1-dioxide acts as a demethylating and dehydrogenating agent. The mechanism of interaction of the dinitrone with donors and acceptors does not involve intermediate charge-transfer complexes probably due to a self association between dinitrone molecules (as supported by X-ray determinations). The crystal structure of the dinitrone was obtained by direct methods;a=9.967 (2),b=19.817 (3),c=10.875 (2) Å, =111.2 (2)°, space group P21/n. The finalR andR w were 0.089 and 0.063 for all measured reflexes.
2,2-Diphenyl-3,3-bi-3H-indol-1,1-dioxid: Molekulare Wechselwirkungen und Kristallstruktur
Zusammenfassung Das Dinitron 2,2-Diphenyl-3,3-bi-3H-indol-1,1-dioxid wirkt als Demethylierungs- und Oxydationsmittel. Die Wechselwirkung des Dinitrons mit Elektronen-Acceptoren und Elektronen-Donatoren geht wegen der Selbstassoziation zwischen den Dinitron-Molekülen ohne die dazwischenliegende Bildung eines Charge-Transfer-Komplexes vor sich; das wird auch von Röntgenstrukturuntersuchungen gestützt. Die Kristallstruktur wurde mit direkten Methoden ermittelt:a=9.967 (2),b=19.817 (3),c=10.875 (2) Å; =111.2 (2)°. P21/n. Die endgültigen WerteR undR w waren 0.089 und 0.063 für alle gemessenen Reflexe.
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14.
Zusammenfassung Cu(I) bildet mit zahlreichen nicht lumineszierenden Thionoliganden (N-monosubstituierten N-Sulfonylthioharnstoffen, N,N-Dialkyl-N-phenylthioharnstoffen und N,N-Dialkylmonothiocarbamaten) rot lumineszierende oktaedrische Cluster (CuL)6. Die Lumineszenz tritt sowohl im Festzustand als auch in Lösungen auf. Abklingzeiten von 10–5s deuten auf kurzlebige Phosphoreszenz hin. Der Einfluß verschiedener Strukturelemente auf die Lage der Emissionsmaxima wird diskutiert. Dabei bewirken Veränderungen in der Metall-Ligand-Koordination die stärkste Verschiebung der Lumineszenzbanden. Tetraedrische (CuL)4-Cluster mit den obigen Thionoliganden zeigen keine Lumineszenz. Generelle Unterschiede in der Struktur oktaedrischer und tetraedrischer Cluster werden diskutiert.Ag(I) bildet nur mit N-Alkyl-N-sulfonylthioharnstoffen lumineszierende Cluster (AgL)6. Die Lumineszenz ist im Gegensatz zu den Cu-Clustern auf den Festzustand beschränkt.
Luminescent Cu(I) and Ag(I) clusters with thiono ligands
Summary Octahedrical (CuL)6 clusters with several non luminescent thiono ligands (N-monosubstituted N-sulfonylthioureas, N,N-dialkyl-N-phenylthioureas and N,N-dialkylmonothiocarbamates) show red luminescence in the solid state and in solution. The luminescence lifetimes of 10–5s are typical of short lived phosphorescence. The emission bands are affected by structural variation of the ligand. Changes of the coordination bonds cause the strongest shifts of the luminescence maxima. Tetrahedrical (CuL)4 clusters with the same thiono ligands are not luminescent. General structural differences between octahedral and tetrahedral clusters are discussed.(AgL)6 clusters are only luminescent in the solid state and if the ligand is a N-monosubstituted N-sulfonylthiourea
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15.
Manganese can be determined by colorimetry with previous oxidation of Mn(II) in a strong basic medium, using 3,3,5,5-tetramethylbenzidine as a chromogenic reagent. The molar absorptivity of the reaction product is 3.4 × 104 mol–1l cm–1l, the detection limit 3 ng/ml, the RSD (0.5 mg/l,n = 8) 0.9% and the calibration range (1-cm cells) 0.02–0.8 mg/1 V(V), Cr(VI) and Co(II) are the most significant interferences. The new method was compared with an AAS procedure (air-acetylene flame) with previous solvent extraction and also with a colorimetric method for the determination of manganese in sea and drinking water.  相似文献   

16.
A new near-infrared (NIR) dye, 1,1-disulfobutyl-3,3,3,3-tetramethylindotricarbocyanine (DTCY) has been developed for the quantitation of proteins in solution. The method is based on the binding of DTCY to proteins under acidic conditions. The binding of DTCY to proteins causes a new band at 814 nm. The maximum binding number of bovine serum albumin (BSA) with DTCY was measured as 100. The linear range is 0.3–40 g mL–1 for BSA and human serum albumin (HSA), respectively. Except for Fe2+, Cu2+, and cetyltrimethylammonium bromide, all of the examined coexisting substances show no interference in the assay. The method has been applied to the quantitation of proteins in serum and urine with recoveries between 96 and 105%.  相似文献   

17.
The coexistence in solution of tautomeric isoxazoline and pyrazoline forms of 1,3-alkanoylhydrazonoximes of acetylacetone has been detected and investigated by1H and13C NMR spectroscopic methods. The compounds indicated eliminate hydroxylamine under the action of acid catalysts, forming 1-acyl-3,5-dimethylpyrazoles.Institute of High Molecular Compounds, Russian Academy of Sciences, St. Petersburg 199004, RussiaTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 825–829, June, 2000.  相似文献   

18.
Summary Synthesis of the hydrochloride oftrans-2-(2-aminocyclohexyloxy)acetic acid (4) fromtrans-2-(2-azidocyclohexyloxy)acetic acid (1) is described.4 was acylated at the amino group to give compounds5–8.1 was converted into acid chloride (9) and amides10–13.
Synthese und Funktionalisierung dertrans-2-(2-Aminocyclohexyloxy)- undtrans-2-(2-Azidocyclohexyloxy)essigsäure
Zusammenfassung Die Synthese destrans-2-(2-Aminocyclohexyloxy)essigsäurehydrochlorids (4), ausgehend vontrans-2-(2-Azidocyclohexyloxy)essigsäure (1), wird beschrieben.4 wurde durch Acylierung der Aminogruppe in die Verbindungen5–8 übergeführt.1 wurde in das Säurechlorid9 und die Carbonsäureamide10–13 umgewandelt.
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19.
3,3,5,5-Tetramethylbenzidine (TMB) is the most commonly used chromogen for horseradish peroxidase (HRP) and so its performance as an electrochemical substrate was evaluated. Measurements of HRP activity in solution were carried out by using an amperometric detector coupled to a flow injection analysis (FIA) system. The enzymatic product was easily detected at a potential of +0.1 V (vs. Ag-pseudoreference electrode) at a bare screen-printed electrode placed in a homemade electrochemical flow cell. A high flow rate (4.3 mL min–1) of 0.5 M H2SO4 was used to obtain repeatable signals and a short analysis time. The detection limit achieved after 15 min of incubation was 2×10–14 M of HRP. The applicability of the amperometric detector to ELISAs was demonstrated by using a commercially available kit for the quantification of interleukin-6 (IL-6) without modifying the kit manufacturers protocol or the reagents for this test.  相似文献   

20.
The results of a study, by thermal mass spectrometric analysis and NMR spectroscopy, of the polycondensation of H-complexes are presented from which it is possible to propose a mechanism for the reaction. It is shown that conversion of the H-complexes into polyimides takes place through the formation of intermediate zwitterions with an amino acid bond after initial separation of methanol, following which elimination of water commences in one stage to form an imide ring. The role of theortho position of the functional groups in the acid ester during the formation of the hydrogen bond is discussed.Institute of Macromolecular Compounds, Russian Academy of Sciences, 199004 St. Petersburg. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2517–2524, November, 1992.  相似文献   

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