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1.
InrecentyearsstUdyondevelopingnovelmimicenZymemodelsthathavebothoNOO-decomPositionandO,'(or.OH)dismutaseabilityisaveryactiveresearchfield1'2.Thesemodelsshowverytwrtanteffectinprovidingprotectionfromtissuedamageassociatedwithvariousmpesofinfiammatorydiseases.MetallopoIPhyrinsassuPeroxidedismutase(SOD)mimicshaveshowedtheabilitytocatalysttheseharmfulradicals.Groveandco-workersrePorted[Mn(III)TMPyP]and[Fe(III)TMPyP]whichhaveshowedveryefficientbehaviorasperoxynitritereductaseandcandep…  相似文献   

2.
Reactions of 5-(p-aminophenyl)-10,15,20-triphenyl porphyrin (1) with Ru3(CO)12 or M(OCOCH3)2 (M=Ni,Mn) afforded metalloporphyrins(4-6),respectively.6-Deoxy-6-io-do-β-cyclodextrin(2) and mono(6-O-trifluoromethanesulfonyl) permethylated β-cyclodextrin(3) reacted with complexes 4-6 to give β-cyclodextrin bonded metal porphyrins (7-9) and permethylated β-cyclodextrin bonded me-tal porphyrins (10-12) respectively.These new complexes were identified by MS,IR,UV-visible and ^1H NMR spectra,and elemental analysis.  相似文献   

3.
The construction of macro-molecular system containing multiple redox centers or photosensitizers is aimportant subject in the design of molecular electronidevices.1,2 For such objectives, systematization of donor-redox center-acceptor triad molecules into largmolecular systems is one of the most feasible approaches, because the exquisite incorporation of thphotosensitizers and suitable electron donors and/oacceptors into a polymeric chain is useful for varioumolecular electronic systems.3-5 Th…  相似文献   

4.
5,15-Di-bithienyl porphyrin (1) and its Cu(Ⅱ), Zn (Ⅱ) complexes (2 and 3)[1] were polymerized according to Scheme 1 by chemical oxidation using FeCl3 as oxidant for making organic conductor, and the linear porphyrin-thiophene copolymers were obtained. The structures of the copolymers were identified by elemental analysis and IR spectra. The conductivity of poly 5,15-di-bithienyl porphyrin (4) doped with FeCl3 was measured to reach over 10-6 S/cm, which was in the range of semiconductor and higher than that of other porphyrin-thiophene copolymers prepared by Shimidzu. The higher conductivity may be due to the better conjugation between the thienyl group and the porphyrin ring. The thienylporphyrins 7 and 8 could not be polymerized under the similar conditions, but could be polymerized by electrochemical oxidation (working electrode: gold-plate electrode; counter electrode: platinum; reference: standard calomel electrode SEC; solvent: 0.1 mol·dm-3 n-Bu4NClO4 in dry MeCN).  相似文献   

5.
5,10, 15-Triphenyl-20-{2- [α- (adenine-9 ) acetylamino]} phenyl porphyrin ( 1 ), 5,10, 15-triphenyl-20-{2-[α-(cytosine-1)acetylamino]} phenyl porphyrin (2), 5, 10, 15-triphenyl-20-{4-[α-(cytosine-1)ethoxy]} phenyl porphyrin (3) and their zinc complexes Zn-1, Zn-2 and Zn-3 have been prepared and characterized by ^1H NMR spectra, elemental analyses, electronic absorption spectra and mass spectra (FAB). Intramolecular π-π interactions and intramolecular metal-~ interaction for 1, 2, Zn-1,and Zn-2 have been investigated by several methods. ^1H NMR studies demonstrate that the porphyrin π-system in 1 and 2 is parallel to the adenine and the cytosine aromatic ring, respectively. The electronic absorption spectral properties of free porphyrin derivatives and their zinc complexes have been compared with those of H2TPP and ZnTPP. The results show that the UV-vis spectra of 1 and 2 are the same as that of H2TPP,whereas the spectra of their zinc complexes show 7 nm red shifts of the Soret bands compared to that of ZnTPP. The emission spectra of Zn-1 and Zn-2 are independent of excitation wavelength. From combination of the evidence of absorption and emission spectra it is suggested the existence of intramolecular metal-π interaction in Zn-1 and Zn-2. The results of conformational analysis agreed quite nicely with that of experiments, thus it was further to validate the experimental conclusions.  相似文献   

6.
Morerecently,thesynthesisofnewdyeswithlargeupconvertedfluorescencebecomesthefocusoftheresearchandhasopenedupamyriadofapplications.Theapplicationsincludetwo-photoninducedlasing',two-photonopticalpowerlimiting',threedimensionalopticaldatastorage',andphotodynamictherapy'.Nevertheless,thistechniquehasneverreacheditsfullpotentialduetothelackofdyeswhichexhibithighupconvertedfluorescentilltensity.ThisrepoFtdescribesthesynthesisandpropertiesoftwo-photoninducedfluorescencedyeswhicharespecificallydesign…  相似文献   

7.
Hydrotalcite-like compounds (HTlc) are composed of trivalent and divalent metal ions, the general formula 1 is: [M2+1-xM3+x(OH)2]x+An-x/n·mH2O M3+ is trivalent metal ions, M2+is divalent metal ions, A is negative ions whose valence is n, and m is the amount of water in the crystal, and x is the molar ratio of trivalent metal ions to all metal ions. A lot of studies have been done on the synthesis and property of HTlc, which is made up of two kinds of the metal ions. It has been found …  相似文献   

8.
Synthetic metalloporphyrin are efficient models of the cytochrome P-450 family ofmono-oxygen enzymes and have been largely used as catalysts in oxidation of alkanesand epoxidation of alkenesl. Polymer-bonded metalloporphyrin reveal many advantageson the catalytic reaction, where the catalysts can be easily separated from the products,recovered, and reused2. Quaternary ammonium salts as phase transfer catalysts werewide used in aqueous-organic two-phase conditions. Unfortunately, most porphyrin…  相似文献   

9.

The purpose of this investigation was to report the synthesis of a novel pH‐sensitive acrylate‐based hydrogel by polymerizing the comonomers 2‐hydroxyethyl methacrylate, HEMA, acrylic acid, AA, and sodium acrylate, NaAc. The NaAc component was obtained by neutralization of AA with sodium hydroxide. Hydrogels were obtained by free radical copolymerization in aqueous solution in the presence of redox initiators, Na2S2O8/Na2S2O5, and ethylene glycol dimethacrylate, EGDMA, crosslinker. The copolymers were synthesized by varying neutralization percent of AA in the range of 10–100. The swelling behavior of the copolymeric gels were investigated as a function of pH, temperature, ionic strength, and AA neutralization percent. The polymer mesh size, ξ, molecular weight between crosslinks, Mc , and crosslinking density, q, were determined by using the Flory‐Rehner equation in the pH range of 2–8 as 8.78–48.8 Å, 209–2667 g/mol, and 0.046–0.59, respectively. The diffusional exponent value, n, of the synthesized hydrogel was found to be 0.59, indicating a non‐Fickian diffusion mechanism. It can be concluded that the hydrogel demonstrated a sharp change in its water absorbency, mesh size and molecular weight between crosslinks of the network with a change in pH of the swelling media. The latter properties suggest strong consideration of these hydrogels for use as oral drug delivery systems and ion‐exchangers for removal of metal ions from aqueous media, owing to the carboxylate groups within the polymeric network.  相似文献   

10.
Two vanadium (IV) complexes [VIVO(Haeae-sal)(MeOH)]+ ( 1 ) and [VIVO(Haeae-hyap)(MeOH)]+ ( 2 ) were prepared by reacting [VO(acac)2] with ligands [H2aeae-sal] ( I ) and [H2aeae-hyap] ( II ) respectively. Condensation of 2-(2-aminoethylamino)ethanol with salicylaldehyde and 2-hydroxyacetophenone produces the ligands ( I ) and ( II ) respectively. Both vanadium complexes 1 and 2 are sensitive towards aerial oxygen in solution and rapidly convert into vanadium(V) dioxido species. Vanadium(V) dioxido species crystalizes as the dimeric form in the solid-state. Single-crystal XRD analysis suggests octahedral geometry around each vanadium center in the solid-state. To access the benefits of heterogeneous catalysis, vanadium(V) dioxido complexes were anchored into the polymeric chain of chloromethylated polystyrene. All the synthesized neat and supported vanadium complexes have been studied by a number of techniques to confirm their structural and functional properties. Bromoperoxidase activity of the synthesized vanadium(V) dioxido complexes 3 and 4 was examined by carrying out oxidative bromination of salicylaldehyde and oxidation of thioanisole. In the presence of hydrogen peroxide, 3 shows 94.4% conversion ( TOF value of 2.739 × 102 h−1) and 4 exhibits 79.0% conversion (TOF value of 2.403 × 102 h−1) for the oxidative bromination of salicylaldehyde where 5-bromosalicylaldehyde appears as the major product. Catalysts 3 and 4 also efficiently catalyze the oxidation of thioanisole in the presence of hydrogen peroxide where sulfoxide is observed as the major product. Covalent attachment of neat catalysts 3 and 4 into the polymer chain enhances substrate conversion (%) and their catalytic efficiency increases many folds, both in the oxidative bromination and oxidation of thioether. Polymer supported catalysts 5 displayed 98.8% conversion with a TOF value of 1.127 × 104 h−1 whereas catalyst 6 showed 95.7% conversion with a TOF value of 4.675 × 103 h−1 for the oxidative bromination of salicylaldehyde. These TOF values are the highest among the supported vanadium catalysts available in the literature for the oxidative bromination of salicylaldehyde.  相似文献   

11.
Bowl-like poly (styrene-co-glycidyl methacrylate) was synthesized by swollen seeded emulsion polymerization. The polymerization was carried out in PS seed emulsion swollen by toluene, whereby the bowl-like particles formed at last. The shape was observed by SEM. These particles became ball-like when swollen by toluene, observed by optical microscope, and the release behavior of solvent from them was examined.  相似文献   

12.
The MgAl layered double hydroxides (LDHs) were prepared by two-stage synthesis, which included mechanochemical activation at the first stage and the interaction of the resulting sample with distilled water at the second stage. The influence of the material of grinding bodies (steel and ceramics), the conditions of activation (activation time and the centripetal acceleration of balls), and the nature of initial compounds on the phase composition of the resulting products was investigated. It was established that the formation of a single-phase MgAl LDH was observed upon mechanochemical activation with the use of steel grinding bodies at an acceleration of 1000 m/s2 for 30 min. The samples prepared by a traditional coprecipitation method and a method that included a stage of mechanochemical activation possessed identical structural parameters. However, the mixed oxides formed upon the calcination of LDHs synthesized by mechanochemical activation were characterized by a more uniform pore space with a pore diameter of 4–5 nm with a developed specific surface.  相似文献   

13.
14.
Ligands capable of positioning two or more very different metal cations, like transition metal and alkali or alkaline earth metal cations, have been described recently1-3. Reinhoudt et al. have synthesized a number of ligands with the cavity for transition metal cations as well as the cavity for alkali metal cations and the corresponding comlexes with different kinds of metal ions4,5. It was anticipated that co-complexation of a hard cation closing to the complexed transition metal cation woul…  相似文献   

15.
The complexes W2{μ-CHCHC(CH3)2](CO)10} and W2{μ-CHCHC(CH3)(CH2)3CH3][(CO)10} have been synthesized, and an X-ray diffraction study has revealed the presence of five CO groups on each metal center. The analogy between W2{μ-CHCHC(CH3)2][(CO)9]} anda complex of W(CO)4 and a tungstabutadiene (CO)5WCHCHC(CCH3)2 prompted the synthesis of the first heteroatom-substitued μ-alkylidene complexes of tungsten, starting from conjugated Fischer-typ carbene complexes (CO)5WC(OR)CHCHR. The X-ray structure of the complex W2{μ-C(OEt)CHCH(CH3)][(CO)9]} has also been determined. In the case of the simplest conjugated compelx (CO)5WC(OR)CHCH2, an interesting rearrangement initiated by addition of W(CO)5 to the terminal CC double bond giving a dinuclear complex W(CO)52-CH2CHC(OMe)W(CO)5] in which the two metal centers are not directly linked, has been observed.  相似文献   

16.
Russian Journal of General Chemistry - Binuclear antimony compounds with a bridging oxygen atom [Ph3SbOC(O)R]2O (R = CF2CF3, CF2CF2CF3), [(4-МеC6H4)3SbOC(O)CF2CF3]2O,...  相似文献   

17.
-Peroxo-bis(4-bromophenoxotri-p-tolylantimony) was synthesized by reacting 4-bromophenol with tri-p-tolylstibine in the presence of hydrogen peroxide. According to X-ray diffraction data, the Sb atoms have trigonal bipyramidal coordination. In the centrosymmetric molecule, the two Sb atoms are joined via bridging peroxo group disordered over two sites. The Sb–O(1,2') bond lengths are equal to 1.999(6) and 2.03(1) Å, the Sb···O(2,1') distances are equal to 2.605(9) and 2.626(5) Å, respectively. The lengths of the terminal Sb–O(3) bonds are 2.093(3) Å.  相似文献   

18.
Zirconium proline-N-methylphosphonate-phosphate (α-ZPMPP) was prepared in the presence of HF for the first time. The α-ZPMPP sample is highly crystallized with interlayer distance of 1.52nm. The interlayer distance of complex of α-ZPMPP with n-butylamine (α-ZPMPP-BA) is in 0.45 nm larger than that of α-ZPMPP. The α-ZPMPP possesses different intercalation behavior of host-guest compound from α-ZP.  相似文献   

19.
A new series of ionic liquids have been prepared containing benzimidazolium cation (abbreviated as Bim). These salts were characterized by DSC, NMR, elemental analysis and thermogravimetric analysis. They showed different properties compared to imidazolium cation due to the introduction of benzene ring. The alkylation of benzene/diphenyl ether with 1-dodecene was carded in C4eBimBr-AlCl3 ionic liquids showing high catalytic activity when the mole ratio of C4eBimB:AlCl3 was 1:2.  相似文献   

20.
The organic olefin ligand 2,5-dimethyl-1-(4-vinyl-benzyl)-piperazine reacts with CuX(X = Cl, Br) to obtain two novel olefin-copper(I) coordination polymers [C_(15)H_(22)N_2Cu_2Cl_3]n(1) and [C_(15)H_(20)N_2Cu_2Br_2]n(2). There are two types of CuX warp structures that have never been seen before in the presence of methanol under solvothermal conditions. The new olefin-copper(I) coordination complex crystallizes in the monoclinic space group P21/c to obtain compounds 1 and 2. Its unique green fluorescence effect can be applied to the LED field.  相似文献   

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