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1.
Yong  Hui  WANG  Man  Zhou  ZHU 《中国化学快报》2003,14(2):159-162
A few of p-nitrobenzoates were synthesized,and the electron transfer of them with β-N,N-dimethylaminonaphthalene (DMAN) in methanol solution was studied.Steady-state fluorescence results showed the cyclodextrin moicty in p-nitrobenzoyl-β-cyclodextrin would block the electron transfer pathway from DMAN compared with other electron acceptors,thus ,reduced the electron transfer efficiency.  相似文献   

2.
Using two β-cyclodextrin derivatives (CDs) with long chain of acyl groups as chiral stationary phases (CSPs) of capillary gas chromatography (CGC), the enantiomers of racemic allethrone and propargyllone were well resolved after derived with acetyl chloride. The enantiomer excess values (e.e.%) of 1S-allethrone and 1S-propargyllone were also determined successfully using these CDs.  相似文献   

3.
Lappaconitine(LA), exhibits antiarrhythm1 and analgesic actions2-5, and has been used to release pain for cancer patients. However, its application is limited due to poor water solubility. But its non-covalent complexes with CDs can solve this problem, th…  相似文献   

4.
OxidativedealkylationoftertiarytaineshasattractedconsiderableattentionduetoitsrelevancetoenzymahcN-dealkylationandasamodelreactionofcytochromeP-450oxidation_1.IthasbeenreportedthattheoxidativedemethylationofN,N-dimethylaniline(DMA)couldbeaccomplishedchendcally_2,electrochemically_3andphotochemically_4.Ingeneral,anelectronacceptivesensitizerorinitiatormustbeusedtoinitiatethephotochemicalreaction,andthereactionproductsandmechanismsdependonthesensitizerorinitiatorused.Forinstance,whendicyanona…  相似文献   

5.
A series of novel β-cyclodextrin polymers was synthesized by immobilization of β-cyclodextrin on the chloromethylated crosslinked polystyrene carriers. The synthetic conditions such as reaction time, temperature, molar feeding ratio of reactants, the degree of crosslinking of polystyrene and the catalysts used were studied in detail and the chemical and physical structures of the formed β-CDpolymers were characterized. Results show that the preparation method is simple and the amount of β-CD immobilized is high. As biomedical adsorbents, they were tested for removal of various endogenous and exogenous toxins such as phenols, aromatic amins, barbitals and unconjugated bilirubin. Results indicate that the adsorptión capacity for those toxins can be enhanced by the inclusion interaction among the β-CD, the substrate molecules and the β-CD polymers.  相似文献   

6.
Phenothiazinederivatives(PTZ)havebeenstudiedfOrdecadesbecauseoftheirwideapplicationsintranquilizingdrugs,dyestuffsandsolarenergyconversionmaterialsI.Recently,westudiedtheelectrontransferreactionsofNsubstilutedphenothiazinewithelectronacceptorsinAcyclodextrin(ffCD)aqueous,olution2'3.TheelectrontransferprocesswassignificantlyinfluencedbythepresenceofffCD.IthasbeennotedthatthePTZwereincludedbyACDtoforminclusioncomplexes.Inthisletter,wereportthestudyofinclusioncomplexationofffCDwithphenoth…  相似文献   

7.
Alumina is widely used as a catalyst or catalyst support in many heterogeneous catalytic processes owing to its high surface area, superior chemical activity and low cost 1. In order to prepare the thermal-stable alumina with high surface area and large p…  相似文献   

8.
The microenvironmental effects of β-cyclodextrin (β-CD) on the twisted intramolecular charge transfer (TICT) of ρ-N, N-dimethylaminobenzaldehyde (DMABA) are investigated using fluorescence spectroscopy. The typical TICT dual fluorescence of DMABA is observed in pure water and aqueous β-CD solution, and β-CD has s remarkable influence on the TICT fluorescence characteristics of DMABA. A linear dependence of the ratio of intensity of TICT fluorescence band (a band) to that of normal fluorescence band (b band) on DMABA concentration is also observed and the introduction of β-CD increases the linear slope. Combined with the results of absorption spectroscopy, fluorescence polarization, and peculiar salt effects, the properties of TICT state of DMABA, the interaction of DMABA with β-CD, and the intrinsic traits of the microenvironmental effects of β-CD are discussed in detail.  相似文献   

9.
Andrographolide (Andro) (Figure 1) is a diterpene lactone isolated from Andrographis paniculate Nees1. It has showed several biological activities including analgesic, antipyretic and anti-inflammatory effects2. However, its poor water solubility and unstability towards oxygen restrained its application. In pharmaceutics, b-CD is used to increase solubility and stability3. We have prepared the inclusion compound of Andro/b-CD (Figure 2) under microwave irradiation4. It has been found…  相似文献   

10.
Two new coordination polymers, [Cd(N3)2(Baep)1/2]n(1) and [Cd2(N3)4(CH3OH)(Bapp)1/2]n(2) (Baep=1,4-bis(2-aminoethyl)piperazine, Bapp=1,4-bis(3-aminopropyl)piperazine) were synthesized. The crystal of 1 is of monoclinic system, space group P21/c with a=9.341(7), b=11.677(9), c=8.195(6), β=93.925(13)°, V=891.8(11)3 , Z=4, μ(MoKα)=2.42 mm-1 , Mr=280.58, Dc=2.090 g/cm3 , the final R=0.0297 and wR=0.0720. The crystal of 2 is of triclinic system, space group PI with a=9.121(5), b=9.666(5), c=10.250(6), α=72.91(2), β=77.10(2), γ=73.95(2)°, V=820.0(8)3 , Z=2, μ(MoKα)=2.62 mm-1 , Mr=522.10, Dc=2.114 g/cm3, the final R=0.0251 and wR=0.0632. Single-crystal X-ray diffraction studies reveal that 1 is a 3D structure based on a dinuclear unit {Cd2(N3)4(Baep)}, in which the Baep ligands formed in situ display two different bridging modes. Compound 2 also has a 3D structure based on a tetranuclear cluster {Cd4(N3)8(CH3OH)2(Bapp)}, in which the azido anions exhibit four different bridging modes (μ-1,1, μ-1,3, μ-1,1,1 and μ-1,1,3). The thermal stability and fluorescent property of 1 and 2 have also been investigated.  相似文献   

11.
A novel donor-acceptor(D-A) triphenylamino terpyridine derivative L was facilely synthesized and fully characterized, and its single crystals were obtained and determined by X-ray diffraction analysis. It crystallizes in triclinic, space group P1 with a = 11.760(5), b =12.516(5), c = 12.850(5) , α = 67.141(5), β = 65.284(5), γ = 75.876(5)o, Mr = 621.54, V = 1575.6(11) 3, Z = 2, Dc = 1.310 g/cm3, μ = 0.245 mm-1, F(000) = 648, the final R = 0.0671 and w R = 0.1869 for 11328 observed reflections with Ⅰ 2σ(Ⅰ). Linear and nonlinear optical properties of terpyridine derivative L were systematically investigated. The maximum two-photon cross-section of L was 382.5 GM(Goeppert-Mayer), measured by two-photon excited fluorescence(TPEF) method. This result demonstrates that the increase of intramolecular charge transfer(ICT) leads to enhanced two-photon absorption(2PA), which could be achieved by introducing additional electron-donor groups to the molecular framework.  相似文献   

12.
Introduction Electron transfer oxidation of DNA by triplet artificial photonuclease reveals a bright prospect of its application in biology and medicine. Both molecular orbital calculation and laser experiments have indicated that the homo guanine sequence should be the final localization site of photoexcited hole via long range migration within DNA. However, the direct observation of the produced ion pairs of biomolecules especially the stabilized radical cation DNA or its components is hampered by the overwhelming transient absorption of protonated radical anion of photosensitizers, such as 2-methyl-1,4-naphthaguinonel (MQ).  相似文献   

13.
A novel determination method of electroinactive molecules by means of electrochemical technique is presented. A new self-assembled monolayer containing cyclodextrin (CD) is prepared with mono(6-o-p-tolylsulfonyl)-β-cyclodextrin. Although this derivatization process leads to a β-CD coverage of 10% of a full monolayer, this layer shows an effective host-guest response to ferrocene. The interfacial ferrocene complexation gives a response similar to that expected for a Langmuir adsorption isotherm yielding a stability constant of 4.2 ×104 mol-1· L and a maximum ferrocene coverage of 8.6×10-12 mol/cm2. The redox peak currents of the surface-confined ferrocene decrease upon addition of competing β-CD guest species to the solution, such as m-toluic acid (mTA) and sodium dodecyl sulfonate (SDS). This principle has been used for the determination of the electroinactive molecules, mTA and SDS in the concentration ranges of 0.8-2.7 μmol/L and 5-100 nmol/L, respectively.  相似文献   

14.
The enamino ketone moiety has attracted much interest because it is a basic and versatile structure for organic synthesis. A number of reviews have been published about the chemistry of β-enamino ketones1-3. It is therefore not surprising that many synth…  相似文献   

15.
Lathyrussalivus(shanhdoninChina,khesariinindiaandBangladesh,peiscarryinFrance,guayainEthiopia)isapopulardroughttolerantcropandimportantgrainlegumeindroughtareaofAfricaandAsia.Thecropisproducedwithminimumamountofcareandsuccessfullygrowninavarietyofclimate.Theedibleseedsareveryimportantnutritionsincetheycontain26-30%protein.However,excessiveingestionofLathe)russalivusseedscanleadtoadiseaseknownaslathyrism.Thelathyrismis.causedbynonessentialaminoacidp-N-oxalyl-L-Q,Ddiaminopropionicacid(P-OD…  相似文献   

16.
Significant progress has been made in understanding the nature of the transition state andthe paths for electron transfer, especially the influences of environmental factors and themolecular properties on the electron transfer rate. These classical and semi-classical, aswell as quantum-mechanical theory, have been very successful in rationalizing severalstructure-reactivity relationships and in predicting novel features of reactivity. Thesemodels established some links between the electron tra…  相似文献   

17.
Compared to the extensive use of samarium diiodide in organic synthesis', little reportsappeared on the application of samarium metal in organic synthesis. As early as 1971Evans and co-workers had prepared phenylsamarium iodide from iodo-benzene andsamarium metal'. But they found that samarium is not so active as ytterbium. In 1986Fukuzawa also prepared the organosamarium intermediate similar to Grignard reagent'.It was Curran who firstly proved and named the samarium Grignard reaction in 19…  相似文献   

18.
Since the discovery of the first sulfinatodehalogenation reaction in 1981 1, great efforts havebeen devoted to this useful reaction. The substrates have been expanded fromperfluoroalkyl iodide (R.I) to per- and poly-fluoroalkyl handes (R,X, X = Br, I, R,CCI,),and many sulfinatodehalogenating reagents such as NaZSZO4, HOCH,SO,Na,H,NC(=NH)SO,H and NaZSZO, have been developed=. Recently, thesulfinatodehalogenation of 2,2,2-trifluoroethyl handes was accomplished by Chen et al.'Howev…  相似文献   

19.
Russian Journal of Organic Chemistry - Chiral norephedrine-based β-amino alcohol bearing a substituted thiophene ring were applied as catalysts for the enantioselective aldol reaction of...  相似文献   

20.
Oneofthemostimportantaimsofphotochemistryisthedesignandconstructionofmoleculardevicesforener gyconversionandinformationprocessing .Thephotoactivemoleculardevicesarebasedonthephotoinducedelectrontransferbetweendonor acceptortypeorganiccompoundsandaccept…  相似文献   

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