简介：ThesynthesisofTs,T10andT12silsesquioxanecagesfromarangeofstartingmaterials:phenyl-cistetrol,1,3-divinyltetraethoxydisiloxaneandcyclopentylTresinsbyusingtetran-butylammoniumfluoride(TBAF)asthecatalystisdescribedinthispaper.Thereactionyieldsobtainedviathecurrentroutearebettercomparedtothoseviatheliteratureroutes.SomeofthecagecompoundshavebeencharacterizedbyX-raycrystallography.

简介：2,5-piperazinedione的新衍生物，1,4-di(2-methoxyphenyl)-2,5-piperazinedione(I)，被N-2-methoxyphenylchloroacetamide，和它的结构的cyclocondensation反应综合被元素的分析，红外，1HNMR和单身者描绘水晶X光检查衍射方法。水晶属于单斜晶的系统，有统一房间尺寸a=0.56934(10)nm的空格组P21/c，b=1.3880(2)nm，c=1.00329(17)nm，=90.376(3)?e

简介：ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｒｅｃｅｎｔｙｅａｒｓ，Ｌａｎｇｍｕｉｒ－Ｂｌｏｄｇｅｔ（ＬＢ）ｆｉｌｍｓｈａｖｅａｔｒａｃｔｅｄｍｕｃｈａｔｅｎｔｉｏｎｂｅｃａｕｓｅｏｆｔｈｅｉｒｐｏｓｉｂｉｌｉｔｉｅｓａｓｆｕｎｃｔｉｏｎａｌｍｏｌｅｃｕｌａｒｄｅｖ...

简介：DensityFunetionalTheory(DFT)methodwasusedinthispapertostudyone-carbontransferfrom1.10-tetrahydroquinoxalinc,ananalogucoftetrahydrofolicaeid,tomethylamine.Thisreaetioncanbecompletedviatwopaths.Fromthecomputationresultwecanconcludethaiageneral-aeidcatalysisexistsinthisreaction.BycomputationwefindDFThasitslimitationindeseribinganewlyincorporatedstructurewithaunitcharge.

简介：Anon-linearoptical(NLO)materialwassynthesizedbymeansofasimplemethod.Thismaterialcanbeappliedinelectro-optical(EO)devices,suchasEOswitchesandmodulators.TheDisperseRed1(DR1)wasdopedinpolymethyl-methacrylate-co-glycidylmethacrylate(PMMA-co-GMA)astheNLOactivechromophore.Thesynthesisprocessandmaterialstructurewereexpressed.Thethermalproperties,surfacemorphologyandopticalcharacteristicsofthematerialwereinvestigatedbymeansofdifferentialscanningcalorimetry(DSC),thermogravimetricanalysis(TGA),atomicforcemicroscopy(AFM),andm-linestechnique.Usingthereflectiontechnique,thevalueoftheelectro-opticalcoefficientγ33wasmeasuredas11pm/Vatawavelengthof1310nm.AnEOswitchwithnanosecondresponsebasedonthismaterialhasbeenfabricated.

简介：由5-溴-2′-脱氧尿苷通过1,2,4-三唑和硫代乙酸在温和的条件下合成4-硫-5-溴-2′-脱氧尿苷,再通过单溴二胺（monobromobimanes,mBBR）对5-溴-4-硫-2′-脱氧尿苷4位硫的亲电反应,合成了用单溴二胺（monobromobimanes,mBBR）标记的5-溴-4-硫-2′-脱氧尿苷,并利用1HNMR核磁共振、质谱和紫外光谱对它们的结构进行了表征,并对它的荧光光谱进行分析和研究.此化合物可以产生极高的荧光特性,由此提供了一条对人体中5-4-硫-2′-脱氧尿苷的检测途径.

简介：DeoxybaccatinⅥ(4α,7β,9α,10β,13α-penta-acetoxy-2α-benzoyloxy-5β,20-epoxytax-11-ene)wasisolatedfromtherootsofTaxuschinensis,Rehd.var.mairei.Thestructuralassignmentsofthecompoundwerebasedontheirspectraldata,including2DNMRexperimentsandchemicalcorrelation.TheX-raycrystallographicanalysisof1-deoxybaccatinⅥprovidedunambiguouscharacterizationforthestructures.Inthestructure,thesix-memberedAringexhibitsboatconformation,theeight-memberedBringadoptsboat-chairconformation,andthesix-memberedCringexhibitsasofaconformation.

简介：WiththedecreaseofpHvaluefrom8.45to–1.0,theUV-Visabsorptionandfluorescentspectraof1,2-bis(4-pyridyl)ethylene(BPE)tookonthesamechangingtrendatfourdifferentsuccessivepHstages:8.45―7.20,7.20―5.62,5.62―2.60,and2.60―-1.0,namely,nochange,decrease,increase,anddecreaseagain.Amongthese,inarangeof7.20―5.62,thefluorescencewavelengthblueshiftedfrom418to359nm,buttheUV-Visabsorptionwavelength,incontrast,redshiftedfrom285to298nm.ThefluorescenceintensityofBPEhadadropeventoquenchuponadeclineinthepHvaluefrom2.60to–1.0probablyowingtoitscation-πinteractiontoreducetheπelectronclouddensityofBPE.Twodissociationconstants,pKa1(4.30±0.01)andpKa2(5.65±0.04),wereobtainedbasedonfluorescencedata.ThechangesoffluorescencespectraindicatethatBPEhas'off-on-off'switchbehavior.ThefluorescentspectraofBPEwerenearlyindependentonthepresenceofα-andβ-cyclodextrins.

简介：

简介：Directasymmetricaldoladditionofmethylketonesto2,2,2-trifluoro-1-phenylethanoneanditsring-substitutedderivativeswasachievedusingL-prolineasachiralpromoter.Variousopticallyactiveβ-trifluoromethyl-β-hydroxyketoneswereobtainedinalmostquantitativeyieldswithmoderateenantioselectivitiesupto64%ee.

简介：Nitricoxidehasplayedanimportantroleinmanyphysiologicalandpathologicalprocessesasakindofimportantgassignalmolecules.Inthiswork,anewfluorescentprobeLysoNO-NaphfordetectingNOinlysosomesbasedon1,8-naphthalimidewasreported.LysoNO-Naphhassub-groupsofo-phenylenediamineasaNOreactionsiteand4-(2-aminoethyl)-morpholineasalysosome-targetablegroup.Thisprobeexhibitedgoodselectivityandhighsensitivity(4.57mmol/L)towardNOinawidepHrangefrom4to12.Furthermore,LysoNO-NaphcanbeusedforimagingNOinlysosomesinlivingcells.

简介：Asupramolecular1Dferromagneticsystemwasstudiedexperimentallyaswellastheoretically.Hybriddensityfunctionaltheory(DFT)calculationswerebasedontheX-rayanalysis.TheresultsofDFTcalculationsandMcConnellmechanismhavecontributedtotheunderstandingofthefactorsgoverningtheexchangecouplingofmagnetisminthecrystalpacking.Boththeexperimentalevidenceandtheoreticalcalculationindicatethatspindensityin2-iodonitronylnitroxide(INN)radicalsconfirms1Dferromagneticchainwithinter-chainantiferromagneticinteraction.

简介：Thesynthesisofanewtypeofhetero-macrocyclicpolyether2,3-henzo-1,4,7,13-tetraoxa-10-selenacyclopentadeca-2-eneisdeseribed.

简介：2,2’-二（1,1’-4-甲基-吡啶）联咪唑（L）、芳香二羧酸与乙酸镉在水热条件下反应得到了配位聚合物[Cd2（L）（p-bdc）2（H2O）2]n（1）和[Cd（L）0.5（m-bdc）]n（2）,并用单晶衍射仪定义了其晶体结构.结构分析表明,配合物1结晶属于正交晶系,Ibca空间群,配合物2结晶属于单斜晶系,C2/c空间群,进一步分析表明,所合成的2个化合物都是有扭曲α-Po拓扑的三维网络结构.在室温条件下,配体L和2个配合物均表现出较好的荧光性质.

简介：采用密度泛函方法对11顶点巢式碳硼烷C2B9H112-异构体进行了几何结构优化,分析了稳定性、电荷分布及分子轨道.结果表明,9个异构体都有对应的稳定构型,保持了巢式骨架结构.C取代开口五元环上B的异构体更稳定,且随取代数目增加和C原子间距增加而增加,C—C键和C—B键作用增强.C取代内层B使异构体稳定性降低,C—C键和C—B键长随之增长.负电荷主要集中在C原子上,开口五元环上的C原子上负电荷要比内层C原子更多,成为亲核取代反应中心.异构体分子前线轨道具有和η5-C5H5-相似的π键性质,ΔELUMO-HOMO反映的化学稳定性与结构能量稳定性趋势一致.

简介：采用密度泛函理论(DFT)方法在B3LYP/6-311++G(d,p)水平下对2种天然酚类化合物(根皮素和根皮苷)进行电子结构、NBO电荷数目、酚羟基氢键解离能和分子轨道能级差4个方面的数据分析.通过分析得出这2种天然酚类化合物抗氧化活性与分子结构中酚羟基、分子内氢键和NBO电荷的数目成正相关,与酚羟基氢键解离能和分子轨道能级差成负相关.理论模型预测结果与实测结果一致.

简介：建立了一种利用液相色谱-原子荧光光谱联用法测定地下水中三价砷和五价砷含量的方法。流动相为磷酸二氢钾和磷酸氢二钠,流速1.0mL/min,方法的标准曲线线性相关性好,进样后在10min内分离、测定完毕,操作自动化程度高,重现性好,方法准确可靠,检出限低（As（3＋）、As（5＋）都是0.02μg/L）,可同时测定地下水中As（3＋）、As（5＋）的含量。

简介：Asimpleandefficientmethodhasbeendeveloped;benzil/benzoinundergoessmoothcondensationwithvarioussubstitutedaldehydeandammoniumacetateinthepresenceofpotassiumdihydrogenphosphate(KH_2PO_4)undermildreactionconditionstoaffordthecorrespondingtrisubstitutedimidazoleinexcellentyields.Themethodforsynthesisofproduct,thereactionmixturewasrefluxinethanolfor40-90min.Thepresentmethodissimple,efficient,andcost-effective.

简介：采用表面等离子共振（SPR）生物传感器，分别固定Aβ及其单克隆抗体于传感芯片表面，实时监测Aβ与Cu（Ⅱ）混合前后与Aβ单抗体特异的结合过程，及Cu（Ⅱ）与Aβ亲和结合及解离情况．结果显示：Cu（Ⅱ）影响Aβ与Aβ单抗体的特异结合能力，加入Ca（Ⅱ）后Aβ不能与Aβ单抗体起特异免疫结合反应；Aβ与Cu（Ⅱ）的结合过程为快结合快解离的动力学过程．

简介：Basedonthestructure-activityrelationshipsofRGD-containingpeptides,aseriesof1,3-dihydro-l,3-dioxo-2H-isoindolederivativesweresynthesized.Allofthemwerefirstreported.Theirstructureswereconfirmedbyspectraldataandelementalanalysis.Theirabilitytoinhibitangiogenesiswereevaluatedinthechickembryochorioallantoicmembraneassayat-10^-5mol/L.Compounds5band5edisplayedobviouslyantiangiogenicactivity.