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1.
Salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides, RCH(OH)CH2N(O)=NO M+ (R=Me, Pri, or But; and M=Li, Na, K, Ag, NH4, or Me4N), were prepared. Their alkylation with alkyl halides R′X (X=Cl, Br, or I) and dimethyl sulfate was studied. Generally, alkylation afforded mixtures ofN-(β-hydroxyalkyl)-N′-alkoxydiazeneN-oxides RCH(OH)CH2N(O)=NOR′ andO-alkyl-N-(β-hydroxyalkyl)-N-nitrosohydroxylamines RCH(OH)CH2N(NO)OR′. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1996–2001, October, 1998.  相似文献   

2.
A heterobimetallic cyano-bridged 1D coordination polymer of the composition [Ni(baepn)(μ-NC)Fe(CN)3(NO)(μ-CN)]n·3H2O has been synthesized by the reaction of nickel(II) nitrate hexahydrate, baepn (baepn = N, N′-bis(2-aminoethyl)-1,3-propanediamine), and sodium nitroprusside dihydrate in a methanol–water mixture. The complex was characterized by physicochemical and spectroscopic methods. The crystal structure was established by single-crystal X-ray diffraction analysis. It reveals cyano-bridged heterometallic chains consisting of alternating arrays of Ni(II) and Fe(II) atoms, both being embedded in distorted octahedral environments. Low-temperature susceptibility measurements show the presence of weak antiferromagnetic exchange interactions between paramagnetic Ni(II) centers (J = −0.46 cm−1) through long diamagnetic [Fe(CN)5(NO)]2− bridges. Spin state of the iron atom was established by 57Fe M?ssbauer spectroscopy.  相似文献   

3.
Three chromium(III) complexes with asparagine (Asn) and histidine (His) of the [Cr(ox)2(Aa)]2− type, where Aa = N,O–Asn, N,O–His or N,N′–His, were obtained and characterized in solution. The complexes with N,O–Aa undergo acid-catalysed aquation to give a free amino acid and cis-[Cr(ox)2(H2O)2], whereas the complex with N,N′–His undergoes parallel reaction paths: (1) isomerization to the N,O–His complex and (2) liberation of an oxalate ligand. Kinetics of the N,O–Aa complexes in HClO4 media were studied spectrophotometrically under pseudo-first-order conditions. The absorbance changes were attributed to the chelate ring opening at the Cr–N bond. The linear dependence of rate constants on [H+] was established, and a mechanism for the chelate ring cleavage was postulated. The existence of a metastable intermediate with O-monodentate Aa ligand was proved experimentally. Effect of [Cr(ox)2(Aa)]2− on 3T3 fibroblasts proliferation was studied. The tests revealed low cytotoxicity of the complexes. Complexes with Ala, His and Cys are good candidates for biochromium sources.  相似文献   

4.
N,N,N′,N′-tetra-2-ethylhexyldiglycolamide (T2EHDGA) has been used for the preferential extraction of 90Y from its mixture with 90Sr from HNO3 as well as HCl medium. The separation efficiencies have been found out under varying experimental conditions. The extracted species were determined from T2EHDGA concentration variation experiments carried out at 3 M nitric acid as well as HCl and were found out to be Y(X3)3·3(TEHDGA)(o) for both the extraction systems, where X = NO3 and Cl, respectively. Comparison of the T2EHDGA and TODGA based separation methods is also made. In order to avoid third phase formation, iso-decanol has been used as the modifier in all the studies. The modifier content was optimized to 30% for 4 M HCl and 20% for 6 M HNO3 as the feed aqueous phases. Separation schemes were developed for the separation of carrier free 90Y and the purity was checked by the half-life measurement method.  相似文献   

5.
Chiral bridge-substituted manganese(III) complexes of N,N′-bis-(2-hydroxynaphthalene-1-carbaldehyde)-(1R,2R)-(−)-diaminocyclohexane and N,N′-bis-(2-hydroxynaphthalene-1-carbaldehyde)-(1S,2S)-(+)-diaminocyclohexane have been synthesized. The interaction of these complexes with calf thymus DNA(CT-DNA) was investigated by spectroscopic, thermal denaturation studies, circular dichroism (CD), and viscosity measurements. Results of spectroscopic and viscosity measurements suggest that the two complexes bind to DNA via an intercalative mode and display enantioselectivity. These Mn(III) complexes have been found to promote the cleavage of plasmid DNA pBR322 in the presence of H2O2.  相似文献   

6.
A method for the synthesis ofO,O-diethyl (N-benzoyl)trichloroacetimidoylphosphonate (1) by successive reaction ofN-(1-diethoxyphosphoryl-2,2-dichlorovinyl)benzamide with Me3SiCl and Cl2 was proposed. The reaction of phosphonate1 with R3P follows the [4+1] cycloaddition mechanism to give phosphoranes, whose stability and further transformations are controlled by the nature of R. Dedicated to the memory of Academician M. I. Kabachnik on his 90th birthday. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2101–2104, October, 1998.  相似文献   

7.
Non-isothermal techniques, i.e. thermogravimetry (TG) and differential scanning calorimetry (DSC), have been applied to investigate the thermal behaviour of carbaryl (1-naphthyl-N-methylcarbamate = 1-Naph-N-Mecbm) and its complexes, M(1-Naph-N-Mecbm)4X2, where M = Cu, X = Cl, NO3 and CH3COO and M = Zn, X = Cl. Carbaryl and Zn(1-Naph-N-Mecbm)4Cl2 complex exhibit two-stage thermal decomposition while the copper(II) complexes exhibit three and four-stage decomposition in their TG curves. The nature of the metal ion has been found to play highly influential role on the nature of thermal decomposition products as well as energy of activation ‘E*’. The presence of different anions does not seem to alter the thermal decomposition patterns. The complexes display weak to medium intensity exothermic and endothermic DSC curves, while the free ligand exhibits two endothermic peaks. The kinetic and thermodynamic parameters namely, the energy of activation ‘E*’, the frequency factor ‘A’ and the entropy of activation ‘S*’ etc. have been rationalized in relation to the bonding aspect of the carbaryl ligand. The nature and chemical composition of the residues of the decomposition steps have been studied by elemental analysis and FTIR data.  相似文献   

8.
Crystal and molecular structure of a new homodrimanic compound (1S,2S,4aS, 8aS)-N-(N-allyldiaminomethanethione)-1-(2-hydroxy-2,5,5,8a-tetramethyldecahydronaphthalenyl) acetamide has been determined by X-ray diffraction analysis. The crystal is monoclinic, unit cell parameters are: a = 9.577(2) Å, b = 7.414(1) Å, c = 16.856(3) Å; β = 94.83(3)°, space group P21, Z = 2, of composition C20H35N3O2S. Two cyclohexan fragments have ordinary structure and chair-configuration typical of this compound class in homodrimanic skeleton. Ethanol molecule is located in the outer sphere. The withdrawal of carbon atoms from planar fragments of cyclohexan rings varies within the limits from 0.722(5) Å to − 0.634(5) Å. A dihedral angle between the mean-square planes of the latter equals 16.0(2)°, torsion angle (5)-(5)-(10)-(16) 171.0(1)° indicates their trans-joint. In the side non linear chain allyl group is connected to terminal nitrogen atom of thiosemicarbazide molecule. Intermolecular hydrogen bonds between carbonyl atom of acetamide fragment, ethanol molecule, and donor-acceptor groups of thiosemicarbazide moiety play the main part in crystal structure organization. Original Russian Text Copyright ? 2005 by E. P. Styngach, S. T. Malinovskii, L. P. Bets, L. A. Vlad, M. Gdanets, and F. Z. Makaev __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 4, pp.785–789, July–August, 2005.  相似文献   

9.
Colloidal dispersions of nanometer-sized platinum colloids were prepared by ethanol reduction of PtCl6 2− in the presence of poly(N-vinylformamide) (PNVF), poly(N-vinylacetamide) (PNVA) or poly(N-vinylisobutyramide) (PNVIBA) and analyzed by UV-vis spectroscopy and transmission electron microscopy. The dispersion stability of each colloid to the presence of added KCl was determined by a stirring and centrifugation procedure. The platinum colloid stabilized by PNVF (PNVF-Pt) was the most stable and its critical flocculation concentration was not observed up to the highest electrolyte concentration employed (4.0 M). The stability of the platinum colloids stabilized by poly(N-isopropylacrylamide) (PNIPAAm) and poly(vinylpyrrolidone) (PVP) was also examined. The sequence of polymer-stabilized platinum colloids in increasing order of dispersion stability was found to be PNIPAAm-Pt < PNVIBA-Pt < PVP-Pt < PNVA-Pt < PNVF-Pt. Received: 25 August 1998 Accepted in revised form: 14 January 1999  相似文献   

10.
The reaction ofN,N′-bis(2-nitroxyethyl)pyridine-2,6-dicarboxamide with PdCl2 afforded previously unknowncis-(N-2-nitroxyethylpicolinamide-N,N′)dichloropalladium(II) andcis-[2-(2-pyridyl)-2-oxazoline-N,N′]dichloropalladium(II), which were isolated as a cocrystallizate of the molecular compounds. Its structure was established by X-ray diffraction analysis. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1604–1606, August, 1999.  相似文献   

11.
2-(Methyl)-4-(arylazo)imidazole (RLH) (1, 2) are new series of azoimidazoles. Upon treatment of alkylhalide in dry THF in presence of NaH has synthesised 1-alkyl-2-(methyl)-4-(arylazo)imidazole (RLR′) (3, 4). They belong to the azoimine family of N,N′-chelating ligand. They stabilize the Cu(I) oxidation state and we have synthesized [Cu(RLR′)2](ClO4) (5, 6). These complexes show a moderately intense visible band (500–600 nm) which has been assigned to 3d(Cu) → π*(ligand) transition. Ag(I) complexes of RLR′ (7, 8) are also very stable under ambient conditions and show weak transitions in the visible region. The Cu(I)-complexes show high potential Cu(II)/Cu(I) redox couple > 0.4 V vs Ag, AgCl/Cl reference electrode. All these complexes have been structurally characterized by 1H NMR spectroscopic data.  相似文献   

12.
Three new potentially hexadentate N4O2 Schiff-base ligands (H2L1, H2L2 and H2L3) were prepared from the reaction of the polyamines N,N′-bis(2-aminophenyl)-1,2-ethanediamine (L1), N,N′-bis(2-aminophenyl)-1,3-propanediamine (L2) and N,N′-bis(2-aminophenyl)-1,4-butanediamine (L3), respectively with salicylaldehyde. Reaction of the Schiff bases with Ni(II) salts in the presence of N(Et)3 gave the neutral complexes [NiL4], [NiL5] and [NiL6]. Ni(II) complexes of the polyamines were also prepared. One of complexes [Ni(L1)(MeCN)2](ClO4)2·MeCN has been characterized through X-ray diffraction methods.  相似文献   

13.
New Pd(II) complexes with 1-allyl-3-(2-pyridyl)thiourea (APTU) of the formulas [Pd(C9H11N3S)Cl2] (I) and [Pd(C9H11N3S)2]Cl2 (II) were obtained and examined by UV-Vis, IR, and 1H NMR spectroscopy. The conditions for the complexation reactions were optimized. The instability constants and molar absorption coefficients of these complexes were calculated. Comparison of the characteristic bands in the UV-Vis and IR spectra of the complexes and free APTU revealed that the ligand in both complexes is coordinated to the metal atom in the thione form in the bidentate chelating mode through the S atom of the thiourea group and the pyridine N atom. In the UV-Vis spectra of the complexes, the charge transfer bands (π → π* Py) and n → π* (C=NPy), (C=S) experience hypsochromic shifts by 450–470 cm−1 caused by the coordination of APTU to the metal ion, which gives rise to ligand-metal charge-transfer bands (C=NPy → Pd, n → π* (C=S)) and (SPd). The protons in the 6-, 4-, and 3-positions of the pyridine ring and the thiourea NH proton in the chelate ring are most sensitive to the complexation.  相似文献   

14.
Co(II), Ni(II), Cu(II) and Cd(II) chelates with 1-aminoethylidenediphosphonic acid (AEDP, H4L1), α-amino benzylidene diphosphonic acid (ABDP, H4L2), 1-amino-2-carboxyethane-1,1-diphosphonic acid (ACEDP, H5L3), 1,3-diaminopropane-1,1,3,3-tetraphosphonicacid (DAPTP, H8L4), ethylenediamine-N,N′-bis(dimethylmethylene phosphonic)acid (EDBDMPO, H4L5), O-phenylenediamine-N,N′-bis(dimethyl methylene phosphonic)acid (PDBDMPO, H4L6), diethylene triamine-N,N,N′,N′,NN″-penta(methylene phosphonic)acid (DETAPMPO, H10L7) and diethylene triamine-N,N″-bis(dimethyl methylene phosphonic)acid (DETBDMPO, H4L8) have been synthesised and were characterised by elemental and thermal analyses as well as by IR, UV–VIS, EPR and magnetic measurements. The first stage in the thermal decomposition process of these complexes shows the presence of water of hydration, the second denotes the removal of the coordinated water molecules. After the loss of water molecules, the organic part starts decomposing. The final decomposition product has been found to be the respective MO·P2O5. The data of the investigated complexes suggest octahedral geometry with respect to Co(II) and Ni(II) and tetragonally distorted octahedral geometry with respect to Cu(II). Antiferromagnetism has been inferred from magnetic moment data. Infrared spectral studies have been carried out to determine coordination sites.  相似文献   

15.
We report the reactivity of three binuclear non-heme Fe(III) compounds, namely [Fe2(bbppnol)(μ-AcO)(H2O)2](ClO4)2 (1), [Fe2(bbppnol)(μ-AcO)2](PF6) (2), and [Fe2(bbppnol)(μ-OH)(Cl)2]·6H2O (3), where H3bbppnol = N,N′-bis(2-hydroxybenzyl)-N,N′-bis(2-methylpyridyl)–1,3-propanediamine-2-ol, toward the hydrolysis of bis-(2,4-dinitrophenyl)phosphate as models for phosphoesterase activity. The synthesis and characterization of the new complexes 1 and 3 was also described. The reactivity differences observed for these complexes show that the accessibility of the substrate to the reaction site is one of the key steps that determinate the hydrolysis efficiency.  相似文献   

16.
N-Methyl-2-(N-ethylcarbozole)-fulleropyrro lidine and N-methyl-2-(4′-N,N-diphenylaminophenyl)-fulleropyrrolidine were synthesized by 1,3-dipolar cycloaddition under microwave irradiation, which were characterized by MS, 1H NMR, IR and UV-Vis. Photoinduced intramolecular electron transfer process from C60 moiety to carbazole moiety has been studied by nanosecond laser flash photolysis. The charge-separated state C60 •−-Cz•+ was observed in the near-IR region with a lifetime of 0.28 μs. The electronic spectrum of the C60-TPA was studied by using ZINDO method on the basis of the optimized geometrics with B3LYP/6-31G* program. The results show that the calculated absorption was beyond 440nm, essentially consistent with the experimental value 433 nm. __________ Translated from Acta Chimica Sinica, 2005,63(17)(in Chinese)  相似文献   

17.
N-(Dimethylfluorosilylmethyl)succinimide (2a) and N-(dimethylfluorosilylmethyl)phthalimide (2b) were synthesized by the Si—N bond cleavage in readily accessible N-(dimethylimidosilylmethyl)imides with BF3 etherate. Analogously, (O→Si)-chelated 1-(dimethylfluorosilylmethyl)-2-pyrrolidone was prepared from 1-(dimethylmorpholinosilylmethyl)-2-pyrrolidone. X-ray diffraction study demonstrated that the silicon atom in the crystals of 2b is pentacoordinated. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 558–561, March, 2006.  相似文献   

18.
四氯合铂酸钾分别与邻、间、对磺基苯甲酸在乙腈和水中利用水热合成获得了3个铂的N-(1-亚氨基乙基)乙脒配合物:[Pt(NIA)_2]·(2-sb)·2H_2O(1),[Pt(NIA)_2]·(3-sb)·3H_2O(2)和[Pt(NIA)_2]·(1,4-dsb)·2H_2O(3)(NIA=N-(1-亚氨基乙基)乙脒,2-sb~2-=2-磺基苯甲酸二价阴离子、3-sb~2-=3-磺基苯甲酸二价阴离子、1,4-dsb~2-=1,4-二磺基苯二价阴离子)。合成过程中发生了乙氰三聚以及4-sb~2-转变为1,4-dsb~2-的反应。对配合物进行了元素分析、红外、紫外、荧光、热重和粉末X射线衍射表征,并利用单晶X射线衍射测定了配合物的晶体结构。3个配合物为阳离子-阴离子物种,阳离子为[Pt(NIA)_2]~(2+),中心金属离子四配位平面构型;阴离子与阳离子、水形成氢键,组成一个三维网络结构,但3个配合物的氢键模式不同。配合物在热稳定性、荧光性质上有一定差异。  相似文献   

19.
2-(5-Benzoacridine)ethyl-p-toluenesulfonate (BAETS), a dual-sensitive probe, was reacted with bile acids in the presence of K2CO3 catalyst in dimethyl sulfoxide (DMSO) solvent to give BAETS–bile acid derivatives. Derivatives exhibited intense fluorescence (FL) with an excitation maximum at λ ex 270 nm and an emission maximum at λ em 510 nm. MS analysis using APCI-MS indicated that derivatives had excellent APCI-MS ionizability with percentage ionization δ values changing from 0 to 88.83% in aqueous acetonitrile and from 0 to 89.15% in aqueous methanol. The collision induced dissociation spectra of m/z [M + H]+ contained specific fragment ions at m/z [M + H−H2O]+, [M + H−2H2O]+, [M + H−3H2O]+, 347.3, and 290.1. Repeatability was good for LC separation of BAETS–bile acid derivatives with aqueous acetonitrile as mobile phase. The relative standard deviations (RSDs) of retention time and peak area at 6.6 nmol mL−1 levels with fluorescence detection (FL) were from 0.045 to 0.072% and from 2.16 to 2.73%, respectively. Excellent linear responses were observed, with regression coefficients >0.9995. The FL detection limits (S/N = 3) were in the range of 18.0–36.1 fmol. The online APCI-MS detection limits are in the range of 500–790 fmol (at a signal-to-noise ratio of 3).  相似文献   

20.
Synthesis and characterization of titanium(IV) and zirconium(IV) complexes of the types Cp2M(Cl)(HPO), Cp2M(HPO)2, Cp2M(ONO) and Cp2M(ONS) (where M represents titanium or zirconium and HPO, ONO and ONS represent the donor sets of the ligands) have been reported. These new derivatives have been prepared by the reactions of titanocene dichloride or zirconocene dichloride with 2-hydroxy-N-phenyl benzamide(HPOH), 1-[(2-hydroxyphenyl)-1-N-phenylamino]hydrazine-carboxamide (HONOH) and 2-hydroxy-N-phenyl benzamide benzothiazoline (HONSH) in different molar ratios. The ligands and their complexes have been characterized by the elemental analyses, conductance measurement, molecular weight determinations and spectral studies. On the basis of electronic, I.r., 1H.-n.m.r. and 13C.-n.m.r. spectral studies, trigonal bipyramidal and octahedral geometries have been proposed for the resulting complexes. All the ligands and their complexes have been screened for their biological activity on several pathogenic fungi and bacteria and were found positive in this respect.  相似文献   

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