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1.
The thermodynamic and geometric parameters of isomeric macrotricyclic Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes with the (NSSN) coordination of the ligand donor centers formed in the reaction of corresponding hexacyanoferrates(II) with ethanedithioamide H2N-C(=S)-C(=S)-NH2 and ethanedial HC(=O)-CH(=O) in gelatin-immobilized matrix implants have been calculated by the hybrid B3LYP density functional theory method with the use of the 6–31G(d) basis set and the Gaussian 03 program package. The bond lengths and bond and torsion angles in these complexes have been reported, and it has been stated that the Mn(II), Co(II), and Cu(II) complexes are nearly planar, the Fe(II) and Ni(II) complexes are slightly nonplanar, while the Zn(II) complex exhibits a rather considerable deviation from coplanarity. The additional five-membered chelate ring resulting from template cross-linking is almost planar in all cases.  相似文献   

2.
Thermodynamic and geometric parameters have been calculated using the hybrid density functional theory method B3LYP with the 6-31G(d) basis set and the Gaussian03 program for the macrotricyclic complexes of Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) with an (NSSN)-coordinated ligand that can result from the complexation of metal hexacyanoferrates(II) with hydrazinomethanethioamide H2N-HN-C(=S)-NH2 and ethanedial HC(=O)-CH(=O) in gelatin-immobilized matrix implants. Bond lengths and valence and torsion angles in these complexes are reported. The Ni(II) and Cu(II) complexes are practically planar. The Mn(II), Fe(II), and Co(II) complexes are characterized by a small deviation from coplanarity, and the Zn(II) complex is noticeably noncoplanar. The additional five-membered metallacycle resulting from template ??joining?? is nearly planar in all complexes.  相似文献   

3.
Complexing processes leading under specific conditions to nickel(II)hexacyanoferrate(II) gelatin-immobilized matrix systems in contact with aqueous-alkaline solutions (pH12) containing dithiooxamide and formaldehyde or glyoxal, have been studied. It has been shown that template synthesis of macrocyclic co-ordination compounds, (2,8-dithio-3,7-diaza-5-oxanonandithioamide-1,9)nickel(II) and (2,7-dithio-3,6-diazaoctadien-3,5-dithioamide-1,8)nickel(II), occurs. Dithiooxamide, formaldehyde and glyoxal act as ligand synthons in this process.  相似文献   

4.
The complexing processes in the triple CoIII–dithiooxamide–methanal and CoIII–dithiooxamide–glyoxal systems taking place in the KCoFe(CN)6-gelatin-immobilized matrix in contact with aqueous-alkaline solutions (pH~12) containing (dithiooxamide + methanal) and (dithiooxamide + glyoxal), have been studied. Template synthesis leading to macrocyclic CoIII coordination compounds with tetradentate N,N,S,S-donor ligands-(2,8-dithio-3,7-diaza-5-oxanonandithioamide-1,9) and (2,7-dithio-3,6-diazaoctadien-3,5-dithioamide-1,8) occurs under these specific conditions. Dithiooxamide, methanal and glyoxal are the ligand synthons in these processes.  相似文献   

5.
The geometric parameters of the molecular structures of (454)macrotricyclic M(II) complexes with a tetradentate chelating ligand with the (NSSN)-coordination of donor sites formed by the template reactions in the M(II)–thiosulfate anion S2O32-–ethylenediamine H2N–CH2–CH2–NH2 have been calculated by the hybrid OPBE/TZVP density functional theory (DFT) method. The standard enthalpies, standard entropies, and standard Gibbs energies of formation of these complexes have been calculated, and a conclusion has been drawn that the template synthesis in these systems is possible when carrying out appropriate reactions under common conditions (in solution of solid phase).  相似文献   

6.
The molecular structures of (5454)macrotetracyclic M(II) complexes with the tetradentate ligand with the (NNNN)-coordination of donor sites formed by the template reactions in the ternary systems M(II)-aminomethanamidine (H2N-C(=NH)-NH2)-3-hydroxy-2-butanone H3C-C(=O)-C(OH)-CH3), where M = Mn, Fe, Co, Ni, Cu, and Zn, have been calculated by the OPBE/TZVP density functional theory (DFT) method. The bond lengths and bond and torsion angles in the complexes, as well as the standard enthalpies, entropies, and Gibbs energies of formation of these compounds, are reported.  相似文献   

7.
The thermodynamic and geometric parameters of asymmetric macrotricyclic Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes with the NSSN-coordination of donor sites of the ligand that can form upon complexation of the corresponding hexacyanoferrates(II) by ethanedithioamide H2N-C(=S)-C(=S)-NH2, hydrazinomethanethioamide H2N-NH-C(=S)-NH2, and 2-oxopropanal in gelatin-immobilized matrices have been calculated by the OPBE/TZVP nonhybrid DFT method with the use of the Gaussian09 program package.  相似文献   

8.
The results of quantum-chemical calculations of the molecular structures of d-metal chelate complexes with compartmental and macrocyclic ligands arising as a result of “self-assembly” processes (template synthesis) to form so-called open and closed contours around the complexing agent have been systematized and generalized. In general, for compounds of both the first and second groups, molecular structures with noncoplanar chelate cores and macrocyclic moieties are more characteristic than coplanar ones. The review covers the works of the author and other researchers carried out mainly over the past 20 years  相似文献   

9.
The geometric parameters of the molecular structures and thermodynamic parameters of formation of macrotricyclic M(II) complexes (M = Mn, Fe, Co, Ni, Cu, and Zn) with the MN2S2 coordination core formed by the reactions of corresponding hexacyanoferrates(II) with hydrazinecarbothioamide H2N-HN-C(=S)-NH2 and 2,4-pentanedione H3C-C(=O)-CH2-C(=O)-CH3 in gelatin-immobilized matrix implants have been calculated by the B3LYP hybrid density functional theory method with the use of the 6-31G(d) basis set and the Gaussian 09 program package. The bond lengths and bond and torsion angles in these chelates have been reported. It has been shown that the Fe(II) and Ni(II) complexes are strictly planar, whereas the Mn(II), Co(II), and Cu(II) complexes are quasi-planar with a rather small deviation of the MN2S2 chelate core from coplanarity, and only the Zn(II) complex is pseudotetrahedral. The additional sixmembered chelate rings resulting from the above processes are almost planar in all chelates.  相似文献   

10.
Heterometallic complex [K3Y(Cat36)3(Dme)4] (I) or binuclear complex [Y2(Cat36)3(Dme)3] · Dme (II · Dme) is synthesized, depending on the reactant ratio, by the reaction of YCl3 with 3,6-bis(tertbutylcatecholate) potassium salt (K2Cat36) in 1,2-dimethoxyethane (Dme). Both complexes are characterized by single-crystal X-ray diffraction analysis (CIF files CCDC nos. 1527929 (I) and 1527930 (II)) and 1H and 13C NMR spectroscopy.  相似文献   

11.
6-Allylsulfanyl-1-arylpyrazolo[3,4-d]pyrimidin-4(5H)-ones react with iodine and sulfuric acid to give angular pyrazolothiazolopyrimidine derivatives. The reaction of 6-(prop-2-yn-1-ylsulfanyl)-1-(4-tolyl)-pyrazolo[3,4-d]pyrimidin-4(5H)-one with sulfuric acid gives angularly fused pyrazolo[4,3-e][1,3]thiazolo-[3,2-a]pyrimidin-4-one, whereas in the reaction with sodium methoxide linearly fused pyrazolo[3,4-d][1,3]-thiazolo[3,2-a]pyrimidin-4-one was formed. Linearly fused pyrazolo[3′,4′:4,5]pyrimido[2,1-b][1,3]thiazole derivatives were also obtained by reaction of 1-aryl-6-(3-phenylprop-2-en-1-ylsulfanyl)pyrazolo[3,4-d]pyrimidin-4(5H)-ones with sulfuric acid.  相似文献   

12.
The structure of peri-hydroxy- and peri-methoxy-substituted aldehydes and ketones of the naphthalene, acenaphthene, and acenaphthylene series and the nature of intramolecular interactions between the peri- substituents therein were determined by spectral (IR, UV, 1H NMR), X-ray diffraction, and quantum-chemical methods.  相似文献   

13.
Ab initio quantum-chemical calculations of 1,2-acetylenedithiol isomers were carried out. The MP2(full), DFT(B3PW91, MPW1PW91), G3, G3B3, and CBS-Q methods were used. According to the calculations, the most stable isomers were 1,2-dithiet, thiiranethione, and trans-1,2-dithioglyoxal. The necessity of including basis set functions with a large angular momentum in calculations was confirmed. The relatively high stability of 1,2-dithiet was attributed to the aromaticity of its four-membered ring. It was noted that the carbon-carbon bond in the three-membered rings of the cis- and trans-isomers of thiirenethiols was unusually short.  相似文献   

14.
A strategy was developed for the synthesis of 7,8,9-trimethyl-1-phenyl-3H-pyrrolo[2,1-d][1,2,5]-triazepin-4(5H)-one, reactions of its functionalization at the С4 atom and aza rings fusion at the С4?N3 bond were explored. The formation mechanism of the pyrrolo-1,2,5-triazepinone scaffold was suggested.  相似文献   

15.
The NiCl2 and CoCl2 complexes with 4,5-(2-pyridylethylene)-dithio-1,3-dithiol-2-thione (L1) and 4,5-(4-pyridylethylene)-dithio-1,3-dithiol-2-thione (L2) were described. The L1 ligand shows bidentate coordination through the pyridyl N atoms and the thiol S atoms in a tetrahedral [CoCl2(L1)] complex (I) and in an octahedral [NiCl2(L1)2](MeCN)2 complex (II). The L2 ligand exhibits monodentate coordination through the pyridyl N atom in tetrahedral complexes [CoCl2(L2)2 (III) and [NiCl2(L2)2] (IV). Complexes I, III, IV in crystal state are octahedral due to extra coordination of the thione S atoms or the chloride bridges responsible for the polymeric structure. The structure of the complex II · CH2Cl2 was determined by X-ray diffraction analysis. The crystals are monoclinic, space group P21/c, a = 11.895(2) Å, b = 13.374(3) Å, c = 21.873(4) Å, β = 95.30(3)°, Z = 2. The Ni atom has quasi-tetrahedral surrounding due to two chloride ions and two L1 ligands coordinated through the pyridyl N atoms and the thiol S atoms.  相似文献   

16.
An efficient method has been developed for the synthesis of 7,16,25-triaryl-7,8,16,17,25,26-hexahydro-6H,15H,24H-tribenzo[f,m,t][1,5,8,12,15,19,3,10,17]hexaoxatriazacyclohenicosines, 3,8-diaryl-2,3,4,7,8,9-hexahydrobenzo[1,2-e:4,3-e′]bis[1,3]oxazines, 3,9-bis(chlorophenyl)-3,4,9,10-tetrahydro-2H,8H-benzo[1,2-e:3,4-e′]bis[1,3]oxazines, and 2,9-bis(chlorophenyl)-1,2,3,8,9,10-hexahydrobenzo[1,2-e:6,5-e′]bis-[1,3]oxazines via cycloaminomethylation of pyrocatechol, resorcinol, and hydroquinone with N,N-bis(methoxymethyl) anilines in the presence of samarium catalysts.  相似文献   

17.
Glucose 2-oxidase (pyranose oxidase, pyranose:oxygen-2-oxidoreductase, EC 1.1.3.10) from Coriolus versicolor catalyses the oxidation of d-glucose at carbon 2 in the presence of molecular O2 producing d-glucosone (2-keto-glucose and d-arabino-2-hexosulose) and H2O2. It was used to convert d-glucose into d-glucosone at moderate pressures (i.e. up to 150 bar) with compressed air in a modified commercial batch reactor. Several parameters affecting biocatalysis at moderate pressures were investigated as follows: pressure, [enzyme], [glucose], pH, temperature, nature of fluid and the presence of catalase. Glucose 2-oxidase was purified by immobilized metal affinity chromatography on epoxy-activated Sepharose 6B-IDA-Cu(II) column at pH 6.0. The rate of bioconversion of d-glucose increased with the pressure since an increase in the pressure with compressed air resulted in higher rates of conversion. On the other hand, the presence of catalase increased the rate of reaction which strongly suggests that H2O2 acted as inhibitor for this reaction. The rate of bioconversion of d-glucose by glucose 2-oxidase in the presence of either nitrogen or supercritical CO2 at 110 bar was very low compared with the use of compressed air at the same pressure. The optimum temperature (55°C) and pH (5.0) of d-glucose bioconversion as well as kinetic parameters for this enzyme were determined under moderate pressure. The activation energy (E a) was 32.08 kJ mol−1 and kinetic parameters (V max, K m, K cat and K cat/K m) for this bioconversion were 8.8 U mg−1 protein, 2.95 mM, 30.81 s−1 and 10,444.06 s−1 M−1, respectively. The biomass of C. versicolor as well as the cell-free extract containing glucose 2-oxidase activity were also useful for bioconversion of d-glucose at moderate pressures. The enzyme was apparently stable at moderate pressures since such pressures did not affect significantly the enzyme activity.  相似文献   

18.
New potential transition state analogue inhibitors for N-acetylglucosyltransferases (GnTs) were synthesised. These compounds based on psico- and tagatofuranose (structure) scaffold contained a 2-thiophenyl-1-O-diethylphosphate moiety mimicking the proposed model of the transition state of the enzymatic reaction catalysed by N-acetylglucosyltransferases. The synthesised compounds as well as their precursors were fully characterised by NMR, optical rotation and mass techniques. Anomeric configuration of tagatofuranose derivatives was confirmed by X-ray crystallography. Two types of potential human glycosyltransferase (GnTs) inhibitors representing donor UDP-GlcNAc, assigned for biological assays on human GnTs, were prepared.  相似文献   

19.
New Cu(II), Co(II), and Pd(II) complexes with benzeneazo-N-tosyl-2-naphthylamine are synthesized by chemical and electrochemical methods and characterized by IR, 1H NMR, and XRD. XRD was used to determine that two six-membered metal rings are formed in transplanar Ni(II) and Pd(II) complexes.  相似文献   

20.
The thermodynamic and geometric parameters of the macrocyclic chelates of Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) with the (NNNN) coordination of the ligand donor centers formed upon complexation between the above metal ions, hydrazinomethanethiohydrazide (H2N-HN-C(=S)-NH-NH2), and 2,3-butanedione (H3C-C(=O)-C(=O)-CH3) in gelatin-immobilized matrix implants were calculated by the B3LYP 6–31G(d) density functional theory method with the use of the Gaussian 09 program package. The bond lengths, valence angles, and torsion angles were reported, and it was noted that the complexes of Fe(II), Co(II), Ni(II), and Cu(II) are almost planar, whereas the complexes of Mn(II) and Zn(II) have a quasi-pyramidal structure of the chelate unit. The additional six-membered metallocycles resulting from template cross-linking, as well as five-membered rings, are almost planar.  相似文献   

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