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1.
Ten dioxide species derived from N,N′-bis(alkylmethyl)-1,2-ethanediamine and N,N′-bis(alkylmethyl)-1,2-propanediamine were tested for their activity withStaphylococcus aureus, Escherichia coli andCandida albicans. A relation between the length of the alkylchain, and/or the molecule asymmetry, and the antimicrobial activity was found. Part V of the series Amine Oxides; part IV: Mlynarciket al.: Folia Microbiol. 24, 188 (1979).  相似文献   

2.
The crystal structure of the complexes (I)Ni[C11N8N2(OH)2]2SO4, (II) Cu[C11H8N2(OH)2]2Cl2· 4H2O and (III) Cu[C11H8N2(OH)2]2(NO3)2·2H2O have been determined by three-dimensional X-ray analysis methods. Crystal data are: (I), monoclinic, space group C2/c, Z = 4, a = 19.666(4), b = 7.994(2), c = 16.045(6) /rA, /gb = 111.231(9)°, (II), monoclinic, space group C2/c, Z = 4, a = 14.504(4), b = 12.333(8), c = 14.630(3) Å, /gb = 90.92°; and (IIl), monoclinic, space group P21/n, Z = 2, a = 7.601(5), b = 11.977(4), c = 14.463(6) Å, β = 93.10(8)°. These structural investigations clearly demonstrate that in each case hydration occurs across the ketone double bond in the ligand and that the resulting hydroxyl group coordinates to the metal. Two di-2-pyridyl ketone ligands are thus bonded to the metal atom in a tridentate fashion. In the nickel complex (I), all six coordination interactions appear to have approximately the same strength. However, in the copper complexes (II) and (III), the pyridyl nitrogens are strongly coordinating to the metal in the equatorial plane, while the hydroxyl groups are more weakly coordinating in the axial direction. The metal to ligand bond distances are: (I) dNi−O = 2.098(4), dNiN = 2.062(4), 2.087(4) Å, (II) dCuO = 2.465(5), dCuN = 1.994(5), 2.006(5) Å, (III) dCuO = 2.464(5), dCuN = 1.990(5), 2.036(5) Å. The neutral diol that results from hydrolysis of di-2-pyridyl ketone is stabilized by coordination to the metal and such coordination is little affected by changes in the metal, the anion or the extent of hydration.  相似文献   

3.
《Inorganica chimica acta》1987,133(2):239-241
Thermodynamic data have been obtained for the reactions in benzene solution at 30°C of tin tetrahalides with the following Lewis bases: triphenylarsine, tetrahydrothiophene, tetrahydrofuran, pyridine-N-oxide, dimethylsulphoxide, dimethylformamide and acetonitrile.Triphenylarsine forms a 1:1 adduct of low stability with tin tetrachloride and fails to react with the other halides. The other bases when they react form both 1:1 and 1:2 adducts, the reactivity decreasing in the order SnCl4 > SnBr4 > SnI4. THT and THF do not react with SnI4; CH3CN does not react with SnBr4 or SnI4. When it is possible to determine data separately for formation of successive adducts it is found that K1 > K2 for SnCl4 and SnBr4 but K1 < K2 for SnI4.  相似文献   

4.
5.
The crystal and molecular structures of the ligand bpenH2 (N,N′-bis(2′-pyridinecarboxamide)-1,2-ethane) and its deprotonated dimeric cobalt(III) complex fac-[Co2(bpen)3]·12H2O have been determined by single-crystal X-ray diffraction methods. Crystal data: (a) bpenH2, C14H14N4O2, orthorhombic, space group Pccn, a=9.638(1), b= 15.288(1), c = 8.684(1) Å, Z=4; (b) Co2(bpen)3· 12H2O, C42H60N12O18Co2, triclinic, space group P1, a = 11.128(3), b = 14.316(5), c = 16.466(4) Å, α= 92.02(2)°, β = 95.21(2)°, γ = 99.30(2)°, Z = 2.The structures were refined to R 0.034 and 0.053 for 1064 and 7748 independent reflexions, respectively. The bpenH2 molecule has a space group imposed centre of symmetry, with the amide group adopting a trans configuration in the closely planar picolinamide moiety. The cobalt complex is dimeric in which three bpen ligands, acting each as a bis(N2-bidentate), bridge the two metal atoms. Each cobalt atom is octahedral with CoNpy 1.944(3) and Co Nam 1.933(3) Å. The Co··Co separation is 5.493(1) Å. The symmetry of the dimeric molecule is D3 which is consistent with that indicated from solution NMR studies.  相似文献   

6.
Synthesis of complexes cis,cis-WVOXL (X=Cl, NCS), cis,trans-WVOXL (X=Cl, OPh, SPh) and cis,trans-WVIE2L (E2=O2, OS, S2) of the title ligand LH2 are reported. cis,cis-WVOCIL crystallises in space group P21/c with a=13.6541(9) Å, b=7.1555(11) Å, c=18.198(2) Å, β=95.294(6)°, V=1770.4(3) Å3 and Z=4 while the cis,trans isomer crystallises in space group P21/n with a=10.361(3) Å, b=14.141(4) Å, c=12.213(5) Å, β=102.56(3)°, V=1747(2) Å3 and Z=4. cis,trans-WVIS2L crystallises in space group P21/n with a=10.645(2) Å, b=13.929(2) Å, c=12.189(2) Å, β=103.14(2)°, V=1760(1) Å3 and Z=4. A short CH3···Cl distance of 3.067(7) Å and an acute OWCl angle of 94.1(2)° are seen in cis,cis-WVOClL, which converts to the cis,trans form on heating in MeCN. The latter isomer features a CH3···Cl distance of 3.38(2) Å and an OWCl angle of 105.1(8)°. Electrochemical and EPR data are reported. In particular, cis,trans-WVIE2L may be reduced to [WVE2L]. EPR properties of these anions and those of complexes WVOXL are discussed in the context of WV centres in tungsten enzymes.  相似文献   

7.
Antibacterial effect of 17 ammonium compounds of the type of N,N′-bis(alkyldimethyl)-α,ω-alkanediammonium dibromides was tested on anaerobically sporulating bacteria of the genusClostridium. A sizable antibacterial activity was displayed by five N,N′-bis(alkyldimethyl)-1,6-hexanediammonium dibromides and by four N,N′-bis(decyldimethyl)-α,ω-alkanediammonium dibromides. These compounds exhibited activity higher than, or comparable with, that of the reference standards Ajatin and Septonex. The maximum antibacterial activity was found in compounds whose alkyl chain contained 9–12 carbon atoms. Compounds with a lower number of carbon atoms in the chain (less than 8) exhibited a low activity.  相似文献   

8.
The synthesis and characterization of a new 14- membered tetraazamacrocylic ligand 5,5,7,12,12,14- hexamethyl-1,4,8,11-tetraazacyclotetradecane-N′,N‴- diacetic acid (H2L2) are reported. Cobalt(III),nickel(II) and copper(II) complexes with this ligand were prepared and their IR and visible spectra studied.The molecular structure of the complex NiL2· HBr·H2O was proved by single-crystal X-ray analysis. The compound crystallizes in the space group P21/n, with cell parameters a = 16.7109(13), b = 9.0539(9), c = 17.0277(13) Å, β = 107.46(6)° and Z = 4. The structure was solved by direct and Fourier methods and refined by full matrix least square calculation to R = 0.042 for 4355 observed reflections (I > 3σ(I)). The complex shows a cis-octahedral geometry with the macrocycle coordinated in a folded configuration to four sites around the central nickel atom. The two carboxylate groups of the side chain are on the same side of the approximate plane of the macrocycle.  相似文献   

9.
《Inorganica chimica acta》1988,141(2):173-177
The group IIb metal dihalide-N,N,N′-trimethylethylenediamine complexes are described. Low frequency infrared spectroscopic studies and conductance data have provided evidence for the formulation and structure of the complexes. The thermal behaviour of these complexes has been examined by thermogravimetry and differential scanning calorimetry. For cadmium and mercury complexes complete loss of ligand occurred followed eventually by sublimation of the metal halide, whereas the zinc complexes sublimed unchanged.  相似文献   

10.
11.
12.
Edward B. Tucker 《Planta》1990,182(1):34-38
The effect of microinjected calcium-loaded 1,2-bis(2-aminophenoxy) ethane-N,N,N,N-tetraacetic acid (CaBAPTA) on cell-to-cell diffusion of carboxyfluorescein (CF) was examined in staminal hairs of S. purpurea Boom. The CaBAPTA was microinjected into the cytoplasm of the staminal hairs either with CF or prior to a subsequent microinjection of CF. The cell-to-cell diffusion of CF along the hair was monitored using enhanced-fluorescence video microscopy. Cytoplasmic streaming stopped in cells treated with CaBAPTA, indicating that intracellular Ca2+ had increased. Cell-to-cell diffusion of CF was blocked in cells treated with Ca-BAPTA. An inhibition of cytoplasmic streaming and cell-to-cell diffusion was observed in the cells adjoining the CaBAPTA-microinjected cell, indicating that the Ca-BAPTA appeared to pass through plasmodesmata. While cytoplasmic streaming resumed 5–10 min after CaBAPTA treatment, cell-to-cell diffusion did not resume until 30–120 min later. These data support an involvement of calcium in the regulation of cell-to-cell communication in plants.Abbreviations BAPTA 1,2-bis(2-aminophenoxy)ethane-N,N,N, N-tetraacetic acid - CF carboxyfluorescein This work was supported by Professional Staff Congress-City University (PSC-CUNY) of New York grant No. 667180 and U.S. Department of Agriculture grant No. 87-CRCR-1-244.  相似文献   

13.
The O′-pivaloyl diesters of N′-acetyl-azanucleosides were obtained from N-[1,3-di(pivaloyloxy)prop-2-yl]-N-(pivaloyloxymethyl)acetamide and a silylated nucleobase under Vorbrüggen's conditions. Unexpectedly, de-pivaloylation of the diesters under basic conditions afforded the corresponding nucleobase and N-acetylserinol. Mechanistic investigations showed that these products result from the following cascade of spontaneous transformations initiated by the mono de-pivaloylation of the starting diesters. N′-Deacetylation of the resultant mono-esters via the intramolecular N-O acetyl migration is the key step of the cascade; the corresponding NH-azanucleosides in the form of O-acetyl-O′-pivaloyl diesters are formed. Fragmentation of these diester intermediates gives the nucleobase and O-acetyl-O′-pivaloylserinol. Conversion of the latter to N-acetylserinol involves the selective O-N acetyl migration followed by de-pivaloylation of the resulting N-acetyl-O-pivaloylserinol.  相似文献   

14.
The novel cis-platinum(II) complexes [(dppe)Pt(μ-OH)]2(BF4)2 and [(dppe)Pt(DMF)2](BF4)2 have been prepared and characterized by 31P NMR, together with cis-[(dppe)Pt(μ-Cl)]2(BF4)2, both in poorly and strongly coordinating solvents (dppe = 1,2-bis(diphenylphosphino)ethane). All these complexes and their dppf analogs (dppf = 1,1′-bis(diphenylphosphino)ferrocene) as well as (dppf)PtCl2, (dppe)PtCl2, (dppf)PdCl2, [(dppf)Pd(μ-Cl)]2(BF4)2 and [(dppf)Pd(μ-OH)]2(BF4)2 have been tested as antiproliferating agents towards Eagle's KB cell-line. Their activity is compared with that of free diphosphine ligands. For Pt(II) complexes, the ID50 figures are found to be higher than those observed for free dppf and dppe. On the contrary, the activity of the palladium dppf complexes is substantially identical to that of free diphosphine.  相似文献   

15.
The He(I) and He(II) photoelectron spectra of a series of [(LL)M(CO)2] (LL = pyrrole-2-CHN′ R; R = t-Bu; M = Rh, Ir) complexes are reported. Assignments are proposed based on He(I)/He(II) intensity differences, on molecular orbital calculations of related complexes and of free ligands, and by comparison with the spectra of the free ligands Hpyrrole-2-CHN′t-Bu, Hpyrrole-2-carbaldehyde and Hpyrrole.The electronic structure of the complexes is discussed and conclusions are drawn about the metal-ligand interaction.  相似文献   

16.
The complexes [Cu(samen)Cu(L)] and [Cu(samen)Ni(L)2] (Lbpy, phen) have been synthesized by the reaction of sodium N,N′-ethylenedisalicylamidatocuprate(II) pentahydrate (Na2- [Cu(samen)]·5H2O), a divalent metal ion, and 2,2′- dipyridyl or 1,10-phenanthroline. Cryomagnetic data for the CuCu complexes did not fit the Bleaney- Bowers equation; but the data did fit a modified Bleaney-Bowers equation
with a large negative J and a significant negative θ, suggesting that a considerable magnetic interaction operates between essentially planar [Cu(samen)Cu(L)] molecules. The magnetisms of the CuNi complexes were well interpreted in terms of the susceptibility equation based on the Heisenberg model. An antiferromagnetic spin-exchange interaction (J= −13∼−14 cm−1) was suggested between the metal ions.  相似文献   

17.
The reaction of(I) (R1 = R2 = Me, Ph and R1 = Ph, R2 = H; X = Ni(II) or Pd(II)) with piperidine or morpholine has been studied and different reaction products have been isolated. The isolated products are categorized into: (i) monoadducts (II), (ii) monosubstituted monoadducts (III), (iii) monosubstituted (IV) and (iv) disubstituted (V) complexes. These complexes have been characterized by infrared, electronic and 1H NMR spectra as well as electron impact and field desorption mass spectra.  相似文献   

18.
Abstract

In an attempt to introduce a substituent at C-2′ in the “up” arabino configuration directly by nucleophilic displacement reaction of a preformed pyrimidine ribonucleoside, we synthesized 2,5′-anhydro-5′-deoxy-2-thiouridine (6) in three steps from uridine. Compound 6 was converted into the 3′-O-acetyl derivative 7. Upon treatment of 7 with triflyl chloride in methylene chloride in the presence of triethylamine and p-dimethylaminopyridine, 2,2′-anhydro-1-(3-O-acetyl-5-chloro-2,5-dideoxy-β-D-arabinofuranosyl)-2-thiouracil (9) was obtained as the only isolable product. Obviously, the intermediate 3′-O-acetyl-2,5′-anhydro-2′-O-triflyl-2-thiouridine (8) was attacked by the chloride nucleophile at C-5′ first giving the 2′-O-triflyl-2-thiouridine intermediate from which 9 was formed by intramolecular nucleopilic reaction.  相似文献   

19.
《Inorganica chimica acta》1988,152(2):135-138
We have prepared and characterized a dimeric complex of the formula Fe2L(OCH3)L′·solvent where L = N,N′-ethylenebis(salicylamine) and L′ = N,N′-ethylene(o-hydroxylphenylglycine)salicylamine. Crystals of the methanol solvate were found to be orthorhombic, space group P2nb, with a = 13.748 (5), b = 22.426(9), c = 11.762(6) Å and dcalc = 1.41 g/cm3. Least squares refinement of 966 reflections gave a final R factor of 0.066. The structure shows that the two iron atoms are coordinated to two different ligands and are bridged by a methoxide ion and a μ-monodentate acetate oxygen from the pendant arm of L′. The magnetic susceptibility was measured over the range 2–300 K and gave a spin coupling constant J = −8.3 cm−1. The significance of acetate bridges to the exchange coupling pathway is discussed.  相似文献   

20.
《Inorganica chimica acta》1986,125(3):173-182
The pre-resonance Raman spectra of 2-formylpyridine thiosemicarbazone have been measured at three pH values corresponding to the fully protonated (H2FPT+), half protonated (HFPT) and deprotonated (FPT) forms of the ligand. Assignments of the vibrations coupled with the π→π* transition have been made by comparison with the spectrum of the deuterated form (DFPT). The pre-resonance Raman spectra of the Zn(II) and Cu(II) complexes, [ZnFPT]+, [CuFPT]+ and [CuHFPT]2+, have also been measured. The spectral pattern of the Cu(II) complexes shows resonance enhancement of vibrations coupled with the π→π*, as well as with the ligand to metal charge transfer transitions. In addition, it is consistent with coordination through thiolate sulfur in [CuFPT]+ and thione sulfur in [CuHFPT]2+.  相似文献   

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