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1.
It has been shown that the reaction of 2, 3-biquinolyls with an excess of lithium in tetrahydrofuran leads to the formation of dianions, treatment of which with water or D2O gives 1, 4-dihydro-2, 3-biquinolyls or their 4-D derivatives in good yield. Oxidation of the latter leads to 4-D-2,3-biquinolyl. The reduction of 2, 3-biquinolyl has been studied.Stavropol State University, Stavropol 355009. Rostov State University, Rostov-on-Don 344090. Russian University of Chemical Technology, Moscow 125190. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1391–1394, October, 1996. Original article submitted September 10, 1996.  相似文献   

2.
Convenient methods for the synthesis of chiral 2,3-seco-2-deoxynucleosides were developed. An isopropylidene protective group was used to block the 3,5-hydroxy groups in 2,3-seco-uridine. Conversion of the hydroxymethyl group to a methyl group was accomplished by chlorination with a mixture of CCl4 and Ph3P with subsequent reduction with n-Bu3SnH. 2,3-seco-2-Deoxyuridine was obtained after deacetonation. The (S) enantiomer was similarly synthesized starting from 1-(-D-arabinofuranosyl)uracil. 3-O-tert-Butyldimethylsilyl-5-O-(p-monomethoxytrityl)-2,3-seco-2-deoxyuridine, which has optically active centers at C(1) and C(4), was also synthesized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 822–826, June, 1988.The authors thank Professor M. Ya. Karpeiskii for his constant interest in this research.  相似文献   

3.
Summary Ruthenium(III) complexes of types [Ru(L)3], [Ru(L)Cl(H2O)2], [Ru(L)Cl2]n, [Ru(L)Cl(H2O)]n(LH =Schiff bases derived from anthranilic acid and benzaldehyde, acetophenone, vanillin, cinnamaldehyde orm-hydroxyacetophenone; LH2=Schiff bases derived from anthranilic acid and salicylaldehyde oro-hydroxyacetophenone; LH=Schiff bases derived fromp-aminobenzoic acid and benzaldehyde, acetophenone, vanillin, cinnamaldehyde orm-hydroxyacetophenone; LH2=Schiff bases derived fromp-aminobenzoic acid and salicylaldehyde oro-hydroxyacetophenone) have been synthesized and characterized on the basis of elemental analyses, conductance, magnetic moment and spectral (electronic, i.r. and1H n.m.r.) data. The wavelengths of the principal electronic absorption peaks have been accounted for quantitatively in terms of crystal field theory and various parameters have been evaluated. On the basis of the electronic spectra, an octahedral geometry has been established for all these complexes except [Ru(L)Cl2]n. The complexes [Ru(L)Cl2]n are pentacoordinate and a trigonal-bipyramidal environment, D3h, is suggested for the ruthenium(III) ion. The thermal behaviour of these complexes has also been studied by t.g., d.t.g and d.s.c techniques. Heats of reaction for the decomposition steps were calculated from the d.s.c. curves. The antifungal and antiviral activities of the complexes with Schiff bases derived from anthranilic acid were also investigated.  相似文献   

4.
Summary Rhodium(I) and iridium(I) mixed complexes of the formulae [M(diolefin)LL]ClO4, [M(diolefin)L2L]ClO4, [(diolefin)LIr(-L)2IrL(diolefin)](ClO4)2, [(diolefin)LM(-L-L)ML'(diolefin)](ClO4)2, [(diolefin)Rh{-(L-L)}2Rh(PPh3)2](ClO4)2 and [(diolefin)LIr{-(L-L)}2IrL (diolefin)](C1O4)2, (L=monodentate sulphur ligand, L-L=bidentate sulphur ligand, L=group Vb ligand; M=Rh, diolefin=1,5-cyclooctadiene (COD) or 2,5-norbornadiene (NBD); M=Ir, diolefin=COD) are described.Author to whom all correspondence should be directed.  相似文献   

5.
Summary New dinuclear complexes, containing a Ru(trpy)(bpy)2+ moiety (bpy = 2,2-bipyridine, trpy = 2,2:6,2'-terpyridine) bonded through cyanide to Ru(NH3) inf5 sup2+/3+ groups have been prepared and characterized by spectroscopic and electrochemical techniques. The formation of cyanide bridges is evident from the i.r. and u.v.-vis. spectra by appearance of v(CN) shifts and changes in max with respect to the mononuclear parent complex [Ru(trpy)(bpy) (CN)]+. In the mixed-valence species Ru infb supII —CN—Ru infa supIII (Rub = Ru bonded to bpy, Rua = Ru bonded to NH3), an intense metal-to-metal charge transfer transition is observed at max = 700 nm in MeCN, with ovv 1/2 = 3.6 × 103 cm–1. From these spectral data and the difference in redox potentials between both metallic centres (determined by c.v. to be E 1/2 = 1.19 V), a value of k th,r = 5 × 105 s-1 has been calculated for the rate of thermal intramolecular electron transfer of the reverse process: Ru ina supII Ru inb supIII . This low value suggests an inverted regime. The complexes studied are thus interesting as models for the design of energy conversion schemes.Presented in part at the XIX Latinoamerican Congress on Chemistry, Buenos Aires, Argentina, November 1990.  相似文献   

6.
Summary Dichloro complexes of PdII, [Pd(L–L)Cl2], where L–L=1-(thiomethyl)-2-(diphenylarsino)ethane (S–As) or 1-(thiomethyl)-2-(diphenylphosphino)ethane (S–P) andtrans-[PdL2Cl2], where L=diphenyl(2-phenylethyl)-phosphine (PE), diphenyl(1-naphthyl)phosphine (PN) orN-methyl-2-thiophenealdimine (SN), have been prepared and characterized. The reactions of these complexes with MeLi were investigated. The dimethyl complexes [Pd(L–L)Me2] (L–L=S–As, S–P) and [Pd(PE)Me2] were isolated and characterized. Reaction of [Pd(L–L)Me2] (L–L=S–As, S–P) with HCl affords the monomethyl derivatives [Pd(L–L)Me(Cl)]. In contrast to the Pt analogues, [Pd(L–L)Me2] and [Pd(L–L)Me(Cl)] are relatively less stable than [Pt(L–L)Me2] and [Pt(L–L)Me(Cl)].  相似文献   

7.
Zusammenfassung Für die Elemente Neon, Natrium, Magnesium, Aluminium und Silizium werden mit einem quantenmechanischen Variationsverfahren unter Verwendung einer minimalen STF-Funktionenbasis Röntgenübergänge vom Typ K 1L1L2 berechnet und den K -Satellit-Linien , , 3, 3 and 4 zugeordnet.
Relation between K -Satellits and X-ray-transitions of the type K 1 L 1L 2 for Ne, Na, Mg, Al and Si
STF-Calculations are reported for X-ray-transitions of the type K 1L1L2 for Ne, Na, Mg, Al and Si. It is shown that these transitions are correlated with the K -satellits , , 3, 3 and 4.


Die Wellenfunktionen können auf Anfrage zur Verfügung gestellt werden.  相似文献   

8.
Refluxing 4,4-isopropylidenediphenol (1) and 5,6-anhydro-1,2-O-isopropylidene--d-glucofuranose (2) with potassium carbonate in dry acetonitrile afforded molecular tweezers (3) and (4) which, on deprotection with aqueous acetic acid, yielded water soluble tweezers (5) and (6). These water soluble tweezers were explored for the solubilization of neutral arenes, viz. naphthalene, biphenyl, durene, fluorene, anthracene and phenanthrene in aqueous medium. These solid liquid extraction studies revealed that 6,6-O-(4,4-isopropylidenediphenyl)bis[-d-glucopyranose] (5) causes an approximate 17-fold increase in the solubility of naphthalene in aqueous medium.  相似文献   

9.
The reaction of dichloro{1-methyl-2-(arylazo)imidazole}palladium(II), Pd(RaaiMe)Cl2 where RaaiMe = p-R–C6H4N=N–C3H2N2-1-Me; R = H(1), Me(2), Cl(3), with pyridine bases [RPY: R = H (a), 4-Me (b), 4-Cl (c), 2-Me (d), 2,6-Me2 (e), 2,4,6-Me3 (f)] has been studied spectrophotometrically in MeCN at 451 nm. The products (4) have been isolated and characterised as trans-Pd(RPy)2Cl2. The kinetics of the nucleophilic substitution has been examined under pseudo-first-order conditions at 298 K. A single phase reaction step has been observed for bases such as Hpy (a), 4-MePy (b) and 4-ClPy (c) and follows the rate law: rate = (a + k[RPy]2[Pd(RaaiMe)Cl2]). The bases 2-MePy (d), 2,6-Me2Py (e) and 2,4,6-Me3Py (f) exhibits a bi-phasic reaction and follows the rate laws: rate–1 = (a + k[RPy][Pd(RaaiMe)Cl2]) and rate–2 = (a + k[RPy][Pd(RaaiMe)-Cl2]), where k is the third-order rate constant; k is the second-order first phase rate constant, k is the second-order second phase rate constant and a/a/a correspond to the solvent dependent constant of the respective reaction path. The rate data supports a nucleophilic association path. External addition of Cl (LiCl) suppresses the rate, which follows the order: k/k/k (3) > k/k,k (1) > k/k,k (2). The k values are linearly related to the Hammett constants. The 2-substituted pyridines (d–f) remarkably reduce the rate and show a bi-phasic reaction behaviour as compared with 4-Rpy (a–c). This is attributed to the steric effect that destabilises the transition state. The rate decreases with increasing steric crowding at the ortho-position and follows the order: (d) > (f) > (e). The 4-substituted pyridines control the rate via an inductive effect and follow the order: (b) > (a) > (c).  相似文献   

10.
The activities and stabilities of coprecipitated Ni/Al2O3 methanation catalysts depend markedly on their preparation and pretreatment. The results are discussed in relation to the structure of the precipitate and to changes which occur during calcination and reduction.
Ni/Al2O3 . , .
  相似文献   

11.
Highly dispersed TiO2-supported copper with strong interactions with the support has been prepared. After reduction at 770 K, H2 chemisorption is suppressed. Two types of copper sites exist, one easily and reversibly oxidized by O2 at room temperature, and another interacting with the support.
, TiO2, . 770 H2 . , O2 , - .
  相似文献   

12.
Zusammenfassung Arylhydrazon-cyanacetylcarbamidsäureäthylester (I) wurde durch Einwirkung einer Na2CO3-Lösung auf 1-Aryl-5-cyan-6-azauracile (II)1,2 cyclisiert. Nitrile (II) wurden durch Addition von Hydroxylamin in entsprechende Amidoxime (III) übergeführt, welche durch Kochen mit Acetanhydrid die zugehörigen 1-Aryl-5-[5-methyl-1,2,4-oxdiazolyl(3)]-6-azauracile (IV) lieferten.
Aryl hydrazone-cyanoacetylcarbamic acid ethyl esters (I) have been cyclized in Na2CO3 soln. yielding 1-aryl-5-cyano-6-azauraciles (II)1,2. Addition of NH2OH to the nitriles (II) gave the corresponding amidoximes (III), which by refluxing with Ac2O were converted to the corresponding 1-aryl-5-[5-methyl-1, 2, 4-oxdiazolyl(3)]-6-azauraciles (IV).
  相似文献   

13.
Ni(II) and Co(II) complexes with deprotonated paramagnetic enaminoketones 4(3,3,3trifluorine2oxopropylidene) 2,2,5,5tetramethyl3imidazolidine1oxyl (L) and 4(3,3,3trifluorine1chlorine2oxopropylidene)2,2,5,5tetramethyl3imidazolidine1oxyl (L1) and alcohols are shown to form continuous solid solutions NixCo1-xL2(C2H5OH)2 and NixCo1-xL2 1(CH3OH)2. Single crystal Xray diffraction analysis showed that concentration variation practically does not affect the structural characteristics of the solid solutions. Distinguishing features if the magnetic behavior of NixCo1-xL2 · (C2H5OH)2 and NixCo1-xL2 1(CH3OH)2 are the antiferromagnetic interaction of the moments of the nickel and cobalt sublattices inside the polymeric layers and the antiferromagnetic nature of interlayer interaction of the magnetic moments.  相似文献   

14.
Compounds of the compositions [2(18-crown-6)6(H2O)2(C2H4Cl2){Pt2+(C2H4)}(Pt2Cl10)2–], [4(18-crown-6)2(OH3)+2(OH2)2(NH3)(Pt2Cl10)2–], [(dibenzo-18-crown-6)6(H2O){Pt2+(C2H4)}(Pt2Cl10)2–], and [4(dibenzo-18-crown-6)2(OH3)+2(OH2)2(NH3)Pt2Cl10)2–] were prepared by reactions of H2PtCl6 with 18-crown-6 and dibenzo-18-crown-6.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1593–1599.Original Russian Text Copyright © 2004 by Guseva, Busygina, Khasanshin, Polovnyak, Yarkova, Yusupov.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

15.
Summary Complexes with 1-methyl-3-(mercaptomethyl)piperidine (LH) and 1-methyl-2-(2-mercaptoethyl)piperidine (LH) Ligands in their thiolato (R), andN-protonated (HR) orN-methylated (MeR) zwitterionic form, of stoichiometry MR2 (M=Ni, R=L or L; M=Cd, R=L), MR (M=Cu or Ag, R=L and L), [Ni(MeR)2]I2 · nH2O (R=L, n=1; R=L, n=2), [Ni(HR)2]X2 (R=L or L, X=ClO4; R=L, X=Br), and [Ag(HR)] ClO4 (R=L) have been prepared and characterized. According to i.r. and electronic spectra, and magnetic measurements the nickel complexes exhibit polymeric frameworks built up from mercapto-bridged metal atoms in square-planar environments. Complexes with copper, silver, and cadmium exhibit similar polymeric arrangements through bridging sulphur atoms but with a different geometry at the metal centers, the first two being mainly linear, as anticipated, and the latter tetrahedral. In no case does coordinationvia nitrogen take place and therefore these ligands behave simply as mercaptides.  相似文献   

16.
Summary CuII and NiII coordination compounds with N,N,N,N-tetrakis[(2-benzimidazolyl)methyl]-1,2-cyclohexanediamine (CDTB) have been prepared and characterized. The crystal structure of [Cu(CDTB)](ClO4)2 has been determined. The geometry around the Cu atom is highly irregular and can best be described as a cis-distorted octahedron, with four short CuN bond distances of 1.988(3) Å and 2.028(3) Å, and two very long CuN bond lengths of 2.543(4) A. The cis NCuN chelate angles in the complex range from 68.8(2) for N(1)CuN(1) to 141.03° for N(4)CuN(1). The cyclic voltammogram of the complex shows a fully reversible one-electron redox wave at E 1/2 = 0.162V versus standard calomel electrode, corresponding to the CuI/II redox couple. The structure of [Ni(CDTB)](NO3)2 ·EtOH has also been determined. The geometry around the Ni atom in this compound can be described as distorted octahedral, with N(4), N(4), N(1), N(1) as the ligating atoms in the basal plane, with cis chelate angles ranging from 79.37(10) to 120.9(2)° with the trans N(2)NiN(2) angle at 175.1(2)°. The structural differences in these two compounds are undoubtedly electronic rather than steric.  相似文献   

17.
Surface tension isotherms ofn-alkylthiopolyoxyerhylene glycols:n-C x H2x+1S(CH2CH2O) y H, wherex=5 to 8,y=3 or 4, were approximated with orthogonal polynomials to get good quality values of surface pressure (II) and molar area of the adsorbed layer (). The modified Volmer (*(–0)=Z*R*T) van der Waals and virial equations of state were used to correlate and in terms of real two-dimensional gas. The combination of Volmer and van der Waals equations of state made it possible to determine the interaction energy, , which was prescribed to cohesion of hydrophobic chains in the adsorption layer. The value of for the amphiphiles in question was in the range 0.97–1.91R*T and the average contribution per methylene group was ca. 0.21R*T.The Lennard-Jones potentials calculated from second virial coefficient were of the same range as , but no clear relation was found between their values and number of structure elements of the alkylthiopolyoxyethlene glycols.Presented during 7th International Conference: Surface and Colloid Science, July 7–13, 1991, Compiegne, France  相似文献   

18.
Cyclophosphate     
Zusammenfassung Der second messenger Adenosin-3,5-monophosphat (A-3,5-MP) wird in den Organismen durch Phosphodiesterase abgebaut. Mit Hilfe einer Reihe verschiedener Cyclophosphate wurde die Abhängigkeit der Phosphodiesterase-Aktivität von der Struktur des Substrates untersucht. Das Enzym aus Herz spaltet Purinribosid-Cyclophosphate schneller als Pyrimidinribosid-Cyclophosphate. 6-Substitution am Purinring vermindert die Spaltgeschwindigkeit, dieser Effekt ist bei Substitution an der 8-Stelle noch stärker. Tritt ein Substituent an die 2O-Stellung, wird die Spaltrate in geringerem Maße wie bei 6-Substitution vermindert. Untersuchungen mit dem Enzym aus Fettgewebe brachten ähnliche Ergebnisse.
CyclophosphatesIII. Splitting of various cyclophosphates by phosphodiesterase from heart and adipose tissue
In organisms, the second messenger adenosine-3,5-monophosphate (A-3,5-MP) is degraded by phosphodiesterase. Employing a series of different cyclophosphates, the structural requirements for phosphodiesterase activity are investigated. With the heart enzyme, purine riboside cyclophosphates are split faster than pyrimidine riboside cyclophosphates. 6-substitution of the purine moiety lessens the splitting rate. This effect is still more pronounced when substitution takes place in the 8-position. Substitution in the 2O-position has also a diminishing effect on the splitting rate, which is less than the effect achieved by 6-substitution. Studies with the enzyme from adipose tissue gave similar results.


II. Mitteilung: Michal, G., du Plooy, M., Woschée, M., Nelböck, M., Weimann, G.: diese Z. 252, 183 (1970).

Wir danken Frau Grudrun Kreutzer, Frl. Gisela Jurz und Herrn Rolf Kieffer für die geschickte und sorgfältige Ausführung der Untersuchungen, sowie Herrn Haid und Herrn Mühlegger für synthetische Arbeiten.  相似文献   

19.
Starting from (+) (2R) methyl 5-ethyl-2,2-spirobiindane-5-carboxylate of known enantiomeric purity 79 optically active, configurationally correlated 5,5,6-trisubstituted 2,2-spirobiindanes (2–7) were prepared for the purpose of testing a shortened polynomal Ansatz for chirality functions. Their optical rotations and1H-nmr spectra are reported.In this context several 6-substituted 5-ethylindanes (1) were prepared as model compounds for synthetic transformations.
  相似文献   

20.
Conclusions The product of conversion of O-bis(2-fluoro-2,2-dinitroethyl)nitromethylbis(2-fluoro-2,2-dinitroethyl)carboxime in methanol or ether is O-bis(2-fluoro-2,2-dinitroethyl)nitromethyl-2-fluoro-2,2-dinitroethyl-2'-fluoro-2-nitroethylenecarboxinie, the structure of which has been established by x-ray diffraction analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2019–2021, September, 1987.  相似文献   

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