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.

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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：标题化合物（C24H16N4S）以噻吩-2-甲醛、苯甲酰乙腈和3-甲基-1-苯基-1H-吡唑-5-胺为原料,在离子液体[bmim]Br溶剂中,在80℃搅拌合成得到.其结构通过单晶X射线衍射法确定,晶体属于三斜晶系,空间群P-1,相对分子质量Mr=392.47,晶胞参数a=0.93612（8）nm,b=1.03063（12）nm,c=1.16624（16）nm,V=0.96853（19）nm3,Z=2,晶胞密度Dc=1.346g/cm3,吸收系数μ=0.185mm-1,单胞中电子的数目F（000）=408.晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子R=0.0585,wR=0.1337.在晶体结构中新形成的吡啶环与吡唑环近似于共平面结构.

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.

简介：运用电化学循环伏安和石英晶体微天平研究了1,4-丁二醇(1,4-BDL)在Pt电极及以Sb和S吸附原子修饰的Pt(Pt/Sbad和Pt/Sad)电极上的吸附和氧化过程.结果表明,1,4-丁二醇的氧化与电极表面氧物种有着极其密切的关系,表面质量变化提供了吸附原子电催化作用的新数据.Pt电极表面Sb吸附原子能在较低的电位下吸附氧,可显著提高1,4-丁二醇电催化氧化活性.与Pt电极相比,1,4-丁二醇在饱和吸附Sb原子的Pt电极上氧化的峰电位负移了0.20V,峰电流增加了1.5倍.相反,Pt电极表面S吸附原子的氧化会消耗表面氧物种,饱和吸附的S原子抑制了1,4-丁二醇的氧化.

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简介：Aseriesofbenzo-fusedheteroaromaticcompoundswith5-,6-and7-memberedtings,suchasbenzimidazole,quinoxalineand1H-1,5-benzodiazepinederivatives,weresynthesizedthroughcondensationreactionofo-pheny1-enediaminewithary1aldehydesorketones.Theexperimentalconditionswerecarefullyexamined,andtheproductswerecharacterizedby^1HNMR,^13CNMR,MS,IRandelementalanalyses.Inaddition,thestructureofabenzodiazaepinederivativewith7-memberedringwasconfirmedbysinglecrystalX-raydiffractionanalysis.

简介：ＩｎｔｒｏｄｕｃｔｉｏｎＨｅｔｅｒｏｂｉｎｕｃｌｅａｒｃｏｍｐｌｅｘｅｓａｒｅｅｒｙｖｅｒｙｉｍｐｏｒｔａｎｔｉｎａｎａｔｅｍｐｔｔｏｍｉｍｉｃｔｈｅｓｔｒｕｃｔｕｒａｌａｎｄｆｕｎｃｔｉｏｎａｌｐｒｏｐｅｒｔｉｅｓｏｆｂｉｏｌｏｇｉｃａｌｓｙｓｔｅ...

简介：Refluxingcalix[4]-1,3-substitutedbenzaldehydederivative(4)withglycinehydrazidederivative,weobtainedanovelcalix[4]arenehydrazonederivative(5)via'1+2'condensationinayieldof78%.Inthereactionofcompound4withL-leucinehydrazidederivativeatroomtemperature,lariatcalix[4]-1,3-aza-crown(6)withchiralaminoacidgroupasbranchedchainwassynthesizedvia'1+1'additioninayieldof70%.Thepreliminaryextractionexperimentssuggestedthathostingcompounds5and6possessedgoodcomplexationabilitiesforα-aminoacids.

简介：应用分子力学、半经验量子化学RM1方法优化了32个抗野生型HIV-1病毒毒株的二芳基嘧啶类（DAPYs）化合物分子结构，从分子构象模型中提取了多种参数并结合疏水性参数与指示性参数建立QSAR多元线性回归方程．回归方程显示：分子体积V的增大会降低其抑制活性，而左苯环与嘧啶环间二面角日增大可以提高抑制活性．同时指示性参数工表明左苯环CN基团加入可以明显增加抑制活性，嘧啶环上R1位置苯基与硝基的加入可以极大降低抑制活性．

简介：Thetitlecomplexi-C4H9Co（salen）（Py）（Py=pyridine.salen=dianionofdisalicylideneethylenediamine）hasbeenfirstsynthesized.ItscrystalstructurehasbeendeterminedbyX-raydiffractionmethod.ThecrystsisaremonoclinicwithspacegroupP21/C.Theunitcellparametesarepresented.ThestructurehasbeenrefinedtoafinalRof0.038.

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