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1.
1,2-(1-Acridin-10'-yl-2-aza-2-methylprop-1,3-ylene)fullerene was synthesized firstly and characterized by UV-Vis, ^1H NMR, ^13C NMR and electrospray ionization mass spectroscopy, which is capable of forming a stable complex with zinc tetraphenylporphyrin via the axial ligation. The steady state fluorescence studies show efficient quenching of the zinc tetraphenylporphyrin emission upon axial coordination of acridine attached to C60.  相似文献   

2.
The binding model of 3-(2-chloropyrid-5-ylmethylamino)-2-cyanoacrylate photosystem Ⅱ (PSⅡ) electron transport inhibitors with the D 1 protein of PSII was built. The high herbicidal activity of this kind of inhibitors was explained by docking studies: in addition to usual factors, the N atom on the pyridine ring could form an H-bond with the backbone amide of Phe265 on the D1 protein. 3D-QSAR analysis on sixteen 3-(2-chloropyrid-5-yl- methylamino)-2-cyanoacrylate compounds was performed using CoMFA method to explain the nature of interactions between the compounds and D1 protein. These studies may provide useful insights for designing new PSII electron transport inhibitors.  相似文献   

3.
李夏 《无机化学学报》2007,23(3):489-493
2-fluorobenzoic acid (2-HFBA) and 2,2′-bipyridine (2,2′-bpy) was used as ligands to react with lanthanum to obtain a complex, [La(2-FBA)3·(2,2′-bpy)]2. The structure of the complex contains three independent molecules. In two of them, the two central metal ions are connected together through four 2-FBA groups by bidentate bridging and chelating-bridging two modes. In another, the two central metal ions are connected together through four bidentate bridging 2-FBA groups. CCDC: 237658.  相似文献   

4.
A series of 2-cyano-3-methylthio-3-substituted methylaminoacrylates were synthesized as herbicidal inhibitors of photosystem Ⅱ (PSⅡ) electron transport, in order to estimate the effect of fluorine atom, pyridyl group, chirality and ester chain on activity. The important intermediate 2-fluoro-5-aminomethylpyridine was synthesized with high yield. The bioassay results showed that most of rifle compounds had high herbicidal activity in postemergence treatment. The introduction of an a-methyl into the 3-substituted methylamino could improve the activity notably. The replacement of hydrogen by chlorine or fluorine group and phenyl by pyridyl group showed different effects, and at the same time, the ester chain affected the activity too.  相似文献   

5.
A series of 1-naphthanilides (1) and 2-naphthanilides (2) with varied substituents at the para- or meta-position of anilino phenyl ring were prepared and their absorption and fluorescence spectra in a nonpolar solvent cyclohexane were investigated. An abnormal long wavelength emission assigned to the charge transfer (CT) state was found for all of the prepared naphthanilides in cyclohexane. A linear free energy correlation between the CT emission energies and the Hammett constants of the substituent was found within series 1 and 2. The value of the linear slope with 1 (0.42 eV) was higher than that with 2 (0.32 eV) being close to that of the substituted benzanilides 3 (0.31 eV) The higher slope value suggested higher charge separation extent in the CT state of 1 than that of 2. It was found that the corresponding linear slope of anilino-substituted benzanilides remained unchanged when para-, meta-, ortho-, or ortho, ortho-methyls were introduced into the anilino moiety, which ruled out the possible contribution of the difference in the steric effect and the electron accepting ability of the naphthoyl acceptor in 1 and 2. Compared with the early reported N-substituted-benzoyl-aminonaphthalene derivatives 4 and 5, it was considered that 1-naphthoyl enhanced the charge transfer in 1 and the proximity of its ^1La and ^1Lb states was suggested to be responsible. It was shown that 1- and/or 2-substituted naphthalene cores acting as either electron acceptor (naphthoyl) or electron donor (aminonaphthalene) were different in not only electron accepting (donating) ability but also shaping the charge transfer pathway.  相似文献   

6.
郑卫红  袁承业 《中国化学》2006,24(9):1170-1174
Reaction of diethyl 2,2-difluoro-3-(a-methylbenzyl)imino-4,4,4-trifluoropropanephosphonate (3) with triethylamine afforded a mixture of normal [1,3]-proton shift reaction product 5 and its HF-eliminated compound 6Z in 1 : 1 ratio. Upon hydrolysis, this reaction mixture gave solely 1,3,3,3-tetrafluoro-2-dioxypropanephosphonate (9). Reaction of 3 with DBU provided only 6, in which the ratio of E/Z forms was dependent on the reaction conditions. Aqueous hydrolysis of 6 led to 9. Catalytic hydrogenation and hydrogenolysis of 6 gave geometric isomers of 11 as expected. The reaction mechanism involved was discussed.  相似文献   

7.
Ethyl 3-alkyl-4-hydroxy-2-thioxothiazolidine-4-carboxylates were prepared in excellent yields from the reaction of corresponding primary amines with carbon disulfide and ethyl 3-bromo-2-oxopropanoate in the presence of anhydrous potassium phosphate in DMF at room temperature within 1 h. The structures of the highly functionalized products were corroborated spectroscopically (IR, ^1H NMR, ^13C NMR, EI-MS) and by elemental analyses. A plausible mechanism for such type of cyclization was proposed.  相似文献   

8.
a-Oxo ketene dithioacetals, methyl 2-(1,3-dithian/dithiolan-2-ylidene)-3-oxobutanoate (2a/2b) prepared in nearly quantitative yields simply from methyl acetylacetate, carbon disulfide and 1,3-dibromopropane/1,2-dibromoethane in the presence of potassium carbonate, were investigated in the thioacetalization with various carbonyl compounds 3. It has been demonstrated that methyl 2-(1,3-dithian-2-ylidene)-3-oxobutanoate (2a) could act as a nonthiolic, odorless and practical thioacetalization reagent. A range of aldehydes and ketones 3 were converted into the corresponding dithioacetals 4 in high yields (up to 91%) in the presence of 2a. Moreover, 2a showed high chemoselectivity between aldehyde and ketone in thioacetalization.  相似文献   

9.
Propyl O-(α-L-rhamncpyranosyl)-(1→3)-[2,4-di-O-(2s-methylbutyryl)-α-L-rham-nopyranosyl]-(1→2)-(3-O-acetyl-β-D-glucopyranosyl)-(1→2)-β-D-fucopyranoside (1), the tetrasac-charide moiety of Tricolorin A, was synthesized in total 23 steps with a longest linear sequence of 10 steps, and overall yield of 3.7% from D-Glucose. The isomerization of the dioxolane-type berzyli-dene in the presence of NIS/AgOTf was observed. Tetrasaccharide 1 exhibited no activity against the cultured P388 cell as Tricolorin A did.  相似文献   

10.
Metal ion-induced aggregation of Aβ into insoluble plaques is a central factor in Alzheimer’s disease. Zn2 is the only physiologically available transition metal ion responsible for aggregating Aβ at pH 7.4. To make it clear that the neurotoxicity of Zn2 -induced aggregation of Aβ on neurons is the key to un- derstand Aβ mechanism of action further. In this paper, we choose Aβ (10-21) as the model fragment to research hippocampal CA1 pyramidal neurons. For the first time, we adopt the combination of spectral analysis with patch-clamp technique for the preliminary study of the mutual relations of Zn2 , Aβ and ion channel from the cell level. The following expounds upon the effects and mode of action of two forms (unaggregated and aggregated) of Aβ (10-21) on hippocampus outward potassium channel three processes (activation, inactivation and reactivation). It also shows the molecular mechanics of AD from the channel level. These results are significant for the further study of Aβ nosogenesis and the devel- opment of new types of target drugs for the treatment of AD.  相似文献   

11.
2-fluorobenzoic acid (2-HFBA) and 2,2′-bipyridine (2,2′-bpy) was used as ligands to react with lanthanum to obtain a complex, [La(2-FBA)3·(2,2′-bpy)]2. The structure of the complex contains three independent molecules. In two of them, the two central metal ions are connected together through four 2-FBA groups by bidentate bridging and chelating-bridging two modes. In another, the two central metal ions are connected together through four bidentate bridging 2-FBA groups.  相似文献   

12.
The new containing Surfur Schiff base Salicylaldelye-2-amino-4-Phenylthiazole(SAPTZ) and its Cu(Ⅱ)、Zn(Ⅱ)、Ni(Ⅱ) and Co(Ⅱ) compelexes were synthesized. The structures of the complexes were characterized by elemental analysis, IR and UV-vis. The peroxidase-like activity of the complexes for the oxidation of Vc with H2O2 was determined.  相似文献   

13.
Thermoanalysis study has been carried out on the complex of bis[1-(2-thienyl)-4,4,4-trifluoro-butanedione- 1,3]copper(Ⅱ) and its adducts with pyridine, 2,2′-bipyridine, quinoline and dimethyl sulfoxide in a dynamic ni-trogen atmosphere by simultaneous TG-DTG-DSC technique. The experimental results showed that the decomposi-tion modes of the solvent molecules were various according to the different structures of the complex, in general, the decomposition of them was ahead of the decomposition of the ligand 1-(2-thienyl)-4,4,4-triflurobu- tanedione-1,3. Among them the adduct with 2,2-bipyridine showed a quite unique thermal behavior. Several methods have been jointly used to study the kinetics of all the thermal decomposition stages for title compounds, which showed that the evolution of the solvent molecules was controlled mainly by Rn mechanism (or Am mechanism for 2,2-bipyridine adduct) with lower activation energy; while the release of 1-(2-thienyl)-4,4,4-trifluro-butane- dione-1,3 was gove- rned by D2 or D3 mode with higher activation energy.  相似文献   

14.
1 INTRODUCTION The molecular assembly of one- or multi-dimen-sional aggregation by hydrogen bonds is now an im-portant subject of supramolecular chemistry and crys-tal engineering[1, . Supramolecular structures formed 2]via intermolecular hydrogen bonds X–H…X or C–H…X (X = O, Cl, N, et al.) are very common inorganic compounds[3~12], and they generally possessdifferent properties due to these hydrogen bonds. Concerning about the spectra of benzene-contai-ning…  相似文献   

15.
2-EAQ is an important intermediate for the synthesis of hydrogen peroxide, pharmaceu- ticals, pesticides, and dyes. With the increasing demand for hydrogen peroxide, it needs to enhance the yields of 2-EAQ. However, in the conventional process, concentrated H2SO41-2 is employed as the catalyst in the dehydration of BE acid for the synthesis of 2-EAQ, which produces a series of environmental impacts and safety concerns. For these reasons, a substitute process, which has little or no hazard…  相似文献   

16.
The organic nanoparticles of a blue-light-emitting molecule, 1,3-diphenyl-5-(9-anthryl)-2-pyrazuline, were prepared by reprecipitation method using acetonitrile as the solvent for the molecular precursor. Three morphologies, spherical, doughnut-shaped and cubic, could be observed on the silicon substrate forthe nanoparfides by the volume-controlled addition of acetonitrile. The evolution of particle morphology as a function of acetonitrile addition was attributed to the variation of the growth habits of the particles in the different environment. The nanoparticles exhibit the novel photoluminescence spectra as compared to those of monomer and the bulk crystals.  相似文献   

17.
The spectrohpotometric determination of Co(Ⅱ) was studied with 1-( 2 -pyridylazo)-2-naphthol in the sodium dodecyl sulphate/n-heptane/water micr oemulsion medium.The apparent molar absorptivity is 1.84×104 L.mol -1.cm-1 at 575 nm.Beer's law is obeyed in the range of 0~ 50 μg/25 mL for Co(Ⅱ).  相似文献   

18.
程琳  应磊  杨小玲  蹇锡高 《中国化学》2005,23(2):200-203
A new monomer diacid, 1,2-dihydro-2-(4-carboxylphenyl)-4-[4-(4-carboxylphenoxy)-3-methylphenyl]phtha-lazin-1-one (3), was synthesized through the aromatic nucleophilic substitution reaction of a readily available unsymmetrical phthalazinone 1 bisphenol-like with p-chlorobenzonitrile in the presence of potassium carbonate in N,N-dimethylacetamide and alkaline hydrolysis. The diacid could be directly polymerized with various aromatic diamines 4a-4e using triphenyl phosphite and pyridine as condensing agents to give five new aromatic poly(ether amide)s 5a-5e containing the kink non-coplanar heterocyclic units with inherent viscosities of 1.30-1.54 dL/g.The polymers were readily soluble in a variety of solvents such as N,N-dimethylformamide (DMF), N,N-dimethyl-acetamide (DMA), dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidinone (NMP), and even in m-cresol and pyridine (Py). The transparent, flexible and tough films could be formed by solution casting. The glass transition tem-peratures Tg were in the range of 286-317℃.  相似文献   

19.
4-(4,6-Dimethylpyrimidin-2-yl)-3-thio-allophanic acid methyl ester was synthesized with mixing 2-amino-4,6- dimethylpyrimidine, potassium thiocyanate and methyl chloroformate in ethyl acetate. Single crystals suitable for X-ray diffraction measurement were obtained by recrystallization from dimethylformamide at room temperature. The crystal belongs to monoclinic symmetry with space group C2/m, and crystal parameters of a= 1.7537(5) nm, b= 0.6759(2) nm, c=1.1148(3) nm, β=118.557(4)°, V=1.1605(6) nm^3, Z=4, De= 1.375 g/cm^3,μ=0.271 mm^-1, F(000)=504, and 1519 [1〉2σ(I)] observable independent reflections were used for the determination and refmement of the crystal structures with final R1 of 0.0372 and wR2 of 0.0992. The theoretical investigation of the title compound was carried out with DRT-B3LYP/6-311G, HF/6-311G and MP2/6-311G methods, and the atomic net charges and the population were discussed.  相似文献   

20.
A stereoselective and economic synthesis of the carbapenem sidechain (2S, 4S)-4-ace-tylsulphanyl-2- [ (S) 1-phenylethyl-carbamoyl] pyrrolidine-l-carboxylic acid 4-nitrobenzyl ester was developed. Due to the effect of spatial hindrance, only the (2S,4S) diastereomer 3 was obtained by coupling 1 and the inexpensive racemic 2 catalyzed by EEDQ.  相似文献   

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