简介:Theimportantintermediateforsynthesesofvariousanti-HIVnucleosideanalogues,methyl2,3-dideoxy-3-fluoro-6-O-(p-methylbenzoyl)-a-D-ribofuranoside,wassynthesizedstartingfrom2-deoxy-D-ribosein5stepswithanoverallyieldof24%.Thisstrategycanbealsousedforsynthesizingotheranalogueswithvarioussubstitutionsat3-Cposition.
简介:Li0.33MnO2cathodematerialwassynthesizedbysolidstatereaction.Thematerialshowedasmallcoherentdomainsizeabout10nmdeterminedbyX-raydiffractionandtransmissionelectronmicroscopy.Theelectrochemicalpropertiesofthematerialwerestudiedindifferentpotentialwindowsof3.5―2.0Vand4.3―2.0V.Anirreversibletransformationtospinelphasewasobservedintheinitialseveralcycles,whichwasmoreprominentoncyclingat4.3―2.0V.ElectrochemicalimpedancespectroscopyshowedthattheLi+diffusioncoefficientofthematerialwasabout2×10–9cm2/s.Li0.33MnO2showedareversibledischargecapacityof140and200mA·h/ginthepotentialwindowsof3.5―2.0Vand4.3―2.0V,respectively.Butthecapacityretentionat4.3―2.0Vwaspoorduetothethickerspinellayerformedonthematerialsurface.
简介:Thetitlecompounds6a—6fwerepreparedwithhighyieldviaintramolecularWittigreactionofmethyl3-perfluoroalkyl-6-perfluoroacyl-2-triphenylphosphoranylidenehex-3,5-dienoates(5a—5i)whichwereobtainedfromthereacitonof3-perfluoroacylprop-2-enylidenetriphenylphos-phoranes(3a—3c)withmethylperfluoroalkynoates(4a—4c).
简介:SYNTHESIS AND SPECTRA STUDIES OF TRANSITION METAL COMPLEXES DERIVED FROM 2, 4-DINITROPHENYL HYDRAZINESYNTHESISANDSPECTRASTUDI...
简介:AnAu/ceria(0.44%,massfraction)catalystcontaininggoldionswaspreparedbyamodifieddepositionprecipitationmethod,andtheevolutionofgoldionsinthecatalystanditsinfluenceonthecatalysisofCOoxidationwereinvestigated.Itwasfoundthattheas-preparedcatalystcontaininggoldionswithhighvalencecouldfullyoxidizeCOat–10°CinitiallybutwasdeactivatedgraduallyatlowtemperaturesduringthereactionwithCOortreatmentbyunpurifiedair.ThedeactivationofthecatalystduringCOoxidationortreatmentofitbyunpurifiedairwasindependentandprogressiveatlowtemperatureswhiletheactivityofthecatalystatrelativelyhightemperatureswasmaintainedwell.DuringthereactionwithCOortreatmentbyunpurifiedair,theXPSresultsindicatethatgoldspeciesevolvedfromhighvalencetolowvalenceandthediffusereflectanceUV-Visspectrashowthathighvalencegoldwasreducedtochargedgoldclusters,goldclustersgrewtosmallgoldcrystalsandsmallgoldcrystalsgrewtolargegoldparticles.Accordingly,thehighvalencegoldcorrespondedtotheactivityatlowtemperaturesandthemetallicgoldwasactiveandrelativelystableathightemperatures.Theturnoverfrequencies(TOF)ofthecatalyststreatedbydifferentmethodsat273Kdecreasedwiththeevolutionofgoldspeciesfromhighvalencetolowvalence,nomaximumofTOFwasobservedalthoughgoldparticlesinthecatalystattainedtoabout2―3nmduringthetreatment.AnAu/ceriacatalystwithagoldloadof0.87%(massfraction)maintainedagoodactivityforCOoxidationwithin18hatroomtemperature.Thecatalystswerecharacterizedviatransmittedelectronicmicroscopy(TEM),inductivelycoupledplasmaopticalemissionspectrometry(ICP-OES),X-raydiffraction(XRD)andBETspecificsurfaceareaandUV-VisDRSaswell.
简介:Luminescentcoordinationcompoundswithnitrogen-containingligandshaveattractedmuchattentionduetotheirgoodperformanceinsensorandelectroluminescentdevicetechniques[1-17].Todevelopnewluminescentmaterials,alargenumberofd10metalcomplexes,especiallyzinccomplexes,withthenitrogen-containingligandshavebeensynthesizedandtheirluminescencebehaviourhavebeenstudied[1-11].Ithasbeenfoundthatforagivencomplex,thesizeoftheπ-conjugatedsystemoftheligandandtheelectroniceffectofsubstituentsattheligandareimportantfactorsformodulatingitsluminescentproperties[5,8,9].
简介:TwoseriesofterritremBanalogues(10a-10cand18)havebeendesignedandsynthesizedfromjujubogenin5awhichwaspreparedfromjujubogeninglycosides5bobtainedfromtheleavesofZizyphusjujuba.Thestructuresofthenewcompoundswereconfirmedby1H-,13C-NMRandMSdata.Compounds10cand18showedweakinhibitoryeffectonAChEat10^-4mol/E.
简介:3-(2-Hydroxyphenyl)-6-(4-nitrophenyl)-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazine,C16H11N5O3S,waspreparedbythecyclizationof3-(2-hydroxyphenyl)-4-amino-5-mercapto-1,2,4-triazolewith2-bromo-4-nitroacetophenone.Thecompoundwascharacterizedbymeansofelementalanalysis,IR,1HNMR,13CNMR,massspectrometry,andX-raydiffraction.ThecompoundcrystallizesinamonoclinicsystemwithspacegroupCc,a=2.1853(4)nm,b=2.1192(5)nm,c=1.3526(3)nm,β=95.21(2)°,V=6.238(2)nm3,Dcalcd.=1.505Mg/m3,Z=16,F(000)=2916,R1=0.0501,wR2=0.0427.Acomparisonbetweenthecrystalstructuresof1,2,4-triazolo[3,4-b][1,3,4]thiadiazineand1,2,4-triazolo[3,4-b][1,3,4]thiadiazolewasmadeinthestructuralview.Atwo-dimensionalnetworkisformedbyhydrogenbondsandπ-πstackinginteractions.
简介:Ionothermalsynthesiswasusedtoprepareanovelaminoacidcontaininghybridzincophosphatemonomer,[Zn(HPO4)(H2PO4)][C6H10N3O2](denotedasZnPO-CJ58).Theinorganicframeworkof[Zn(HPO4)(H2PO4)]·[C6H10N3O2]consistsof4-memberedringsformedbyZnO3OHisandPO2(OH)2tetrahedra.TheHPO4andaminoacidmoietieshangontheZncenter.Suchaframeworkisstabilizedbyextensivemultipointhydrogenbondsinvolvingthephosphateunitsandhistidinemoleculestoformapseudo-3Dsupramolecularstructure.ItisnoteworthythatZnPO-CJ58isthefirstzincphosphateclusterwithaminoacidactingastheligand.Itexhibitsphotoluminescenceexcitedatawavelengthof220nm.Interestingly,ZnPO-CJ58cantransformintoalayeredstructure(C6H10N3O2)Zn2·(HPO4)(PO4)·H2O(ZnPO-CJ36)throughfurtherreactingwithwaterorzincacetatedihydrateinwaterat85℃for1h.Thisworkwillbehelpfulforthesynthesisofcrystallineinorganic-organichybridmaterialswithbiofunctionalmolecules.
简介:采用一步法合成了氨基化四氧化三铁(NH2-Fe3O4)磁性纳米材料,并以XRD,IR等手段对其进行了表征.将NH2-Fe3O4组装到磁性玻碳电极表面,得了NH2-Fe3O4修饰的磁玻碳电极,并以该修饰电极为工作电极,研究了其电化学性能.利用差分脉冲溶出伏安法研究了铅(Ⅱ)离子和铜(Ⅱ)离子在该修饰电极上的电化学行为.结果表明:NH2-Fe3O4纳米粒子可显著提高Pb2+和Cu2+在电极表面的富集量,提高溶出峰电流.由于差分脉冲溶出伏安曲线中Pb2+和Cu2+的溶出峰电位差较大,且没有相互干扰,所以该电极可用于Pb2+和Cu2+的同时测定.
简介:通过水热法合成了一维链状的磷钼氧酸盐(DETA)。NaNa(H5P4Mo6O31)2]·8H2O(DETA—Diethylenetriamine),采用x-射线单品衍射结构分析,元素分析和红外光谱等表征.该磷钼氧酸盐属于三斜晶系,空间群是P-1,晶胞参数a=1.2434(3)nm,6—1.2610(3)nm,c=1.3079(3)nm,a=85.418(3)°,β=73.399(2)°),γ=82.175(3)°,V=1.9450(8)Elm。,F(000)=1462,Z=:=2.标题化合物的结构是由Na(H5P4Mo6O31)2簇单元,二亚乙基三胺阳离子和结晶水分子组成.另外,Na(H5P4Mo6O31)2簇由钠离子连接形成了一维的链结构.一维链结构又由于二亚乙基三胺阳离子和结晶水分子形成的氢键进一步连接三维超分子结构.用标题化合物修饰的碳糊电极(APM—CPE)对AA氧化有很好的电催化活性.
简介:Inanattempttofindnewantitumoragents,anovelclassofchromonecompoundswithabenzimidazoleorabenzoxazoleringinpositions2or6weresynthesizedviacondensationinpolyphosphoricacid(PPA)byusingchromoneacidsasthestartingmaterials.Duringthepreparationprocess,itwasfoundthatPPAcouldcleavethechromoneringtoproducearing-openingcompound(6).Themolarratioofthechromonecompound(5)tothering-openingcompound(6)variedwiththechangeofreactiontemperatureandtime.BasedonMTTprotocol,theantitumoractivityofeachofthecompoundsobtainedwasevaluatedagainstthreehumancancercelllines:KB(oralepidermal),A2780(ovary)andBel7402(liver).TheIC50variedfrom54.7μmol/Ltomorethan180μmol/L.
简介:Thesolvent-freemechanochemicalreactionandtheliquid-phasereactionofC60withethyl2-diazopropionatepreparedinsituorpreformedfromalanineethylesterhydrochlorideandsodiumnitritehavebeeninvestigated.Methanofullerene1andfulleroids2and3fromthesereactionswereobtained,meanwhilethepyrazolineintermediatewasnotobserved.Fulleroids2and3canbeconvertedtomethanofullerene1inrefluxingtoluene.