学科分类
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17 个结果
  • 简介:NaphtholgreenBwasused,forthefirsttime,asanewmediatorinanamperometricglucosebiosensor.Itisagoodmediator,promotingelectrontransferfromglucoseoxidasetographiteelectrode.Thebiosensorshowshighsensitivitytoglucoseatlowpotentialwithresponsetimeof30seconds.Thelinearrangeisfrom1.5to18μmol/Lglucosewithdetectionlimitof0.5μmol/Lglucose.

  • 标签: 萘酚绿B 介体 葡糖氧化酶 生物传感器
  • 简介:AbinitiomolecularorbitalcalculationsofdoublynegativechargedB16H162-(D2)andneutralB16H16(Td)havebeendoneattheHF/6-31Glevel.TheyarepredictedtobechemicallyandkineticallystablebyvibrationalanalysesontheirrespectiveenergyhypersurfaceoftheHF/6-31Glevel.ThegeometricalstructureofthespeciesB16H1622-(D2)wasdiscussed.

  • 标签: Closo BORON hydrides ab INITIO MOLECULAR
  • 简介:FluorescencequenchingofjanusgreenB(JGB)insodiumdodecylsulfate(SDS)micellebynucleicacids(DNA)wasstudiedusingUV-visabsorption,steadystatefluorescenceemissionmethodsandlifetimemeasurements.IntheSDSmicelle,weakfluorescenceofJGBwasenhanced,andthemaximumemissionshiftedfrom425to410nm.InthepresenceofDNA,thefluorescenceofJGBwasquenched.Linearrelationshipsbetweenthefluorescencequenching(F0/F)andconcentrationsofDNAwereobservedintherangeof2.4×10^-8to1.08×10^-7mol·L^-1forcalfthymusnucleicacids(ctDNA)and1.9×10^-8to3.8×10^-8mol·L-1forfishspermnucleicacids(fsDNA)when2.5×10^-5mol·L^-1JGBwasemployed.Thelimitdetectionwere1.3×10^-8mol·L^-1forctDNAand6.4×10^-9mol·L^-1forfsDNA.AthighDNAconcentration,therewasasystematicdeviationfromtheStem-Volmerequationduetothestaticanddynamicquenchingoccurringsimultaneously.TheproposedmethodwasappliedtothedeterminationofthenucleicacidsinchickenbloodextractionandtheanalyticalresultswereingoodagreementwiththeUV-method.

  • 标签: 核酸 探测器 DNA 生物技术 烟鲁绿B 十二烷基硫酸钠
  • 简介:FournewtaxanediterpenoidswereisolatedfromthebarkofTaxusyunnanensis.Theirstructureswereelucidatedasthenewskeletonwith5/7/6/4memberedringsbyspectralanalysisand2DNMRshiftcorrelationexperiments.

  • 标签: skeleton membered TAXUS BENZOYL belongs fused
  • 简介:TwoseriesofterritremBanalogues(10a-10cand18)havebeendesignedandsynthesizedfromjujubogenin5awhichwaspreparedfromjujubogeninglycosides5bobtainedfromtheleavesofZizyphusjujuba.Thestructuresofthenewcompoundswereconfirmedby1H-,13C-NMRandMSdata.Compounds10cand18showedweakinhibitoryeffectonAChEat10^-4mol/E.

  • 标签: 合成 2-内-l-安息香酸盐 TerritremB相似物 Jujubogenin 配糖基 药物提取
  • 简介:ThemethanolicextractfromaChineseendemicChrysanthemumplant,Dendranthemaindicumvar.aromaticum,wasfoundtoshowhighantifeedingactivityagainstPierisbrassicaeL.,andbybioassay-guidedseparation,theactivecomponent,B-ring-homo-tonghaosu,2-(2',4'-hexadiynylidene)-1,6-dioxaspiro-[4,5]-dec-3-ene(2)wasisolated.Itsstructurewaselucidatedbycomparingitsspectroscopicdatawiththoseof2reportedintheliteratures.FurthermorenewconvenienttotalsynthesismethodsofB-ring-homo-tonghaosuwerealsodevelopedtoconfirmitsstructureandmakeitsfurtherapplicationincropprotectionavailable.Inaddition,extensivecomparisonofspectroscopicdatashowedthatthestructureofcompound21reportedinliteratureshouldberevisedto2.

  • 标签: 离析 结构 合成 拒食素
  • 简介:极其细小磨擦非结晶的合金催化剂被化学减小与KBH4准备。在在气压的cinnamaldehyde的液体阶段加氢期间,Ru-B催化剂准备了展出优秀选择到cinnamyl酒精。当加氢与超声的照耀被执行时,当到cinnamyl酒精的选择仍然保持几乎未改变时,反应率能极大地被提高。加氢率超声的频率或照耀时间的增加被增加。根据各种各样的描述,例如XRD,XPS,TEM,赌注和ICP,结构、电子的特征上的超声的照耀的效果磨擦催化剂简短被学习。同时,催化表演上的ultrasonication的提升效果也基于cinnamaldehyde的选择加氢被讨论到cinnamyl酒精。

  • 标签: 钌-硼无定形合金 催化剂 超声照射 肉桂醛 肉桂醇 催化加氢
  • 简介:HeteroatomM-ZSM-12zeolites(M=B,Al,Ge,Ga,Fe)arehydrothermallysynthesizedanditisprovedthattheheteroatomMisinvolvedintheframeworkofsynthesizedmolecularsievesbymeansofXRD,IRspectra.TheresultsofadsorptionanddiffusionexperimentsindicatethattheheteroatomMmodifiestheporevolume,specificsurfacearea,andthechannelofZSM-12molecularsieves.

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

  • 标签: refined PYRIDINE MONOCLINIC compl alkyl DALTON
  • 简介:用量子化学密度泛函理论(DFT)、分子力学(MM)及模式识别方法,对34个新型均三氮苯衍生物进行了结构活性关系研究.结果表明,影响此类衍生物分子除草活性的主要因素有C(1)上所带的电荷Qc(1),分子总能量E,分子生成热Ef,溶剂可及面积SGrid,分子体积V和C(3)上所带的电荷Qc(3)等参数.通过在C(1)上加上吸电子基,降低C(1)上的电荷,以及在C(3)上连接单取代氨基可以提高除草活性.所得模型对化合物生物活性有较好的预测效果.

  • 标签: 量子化学 密度泛函理论 构效关系 模式识别
  • 简介:采用B3LYP方法在6—31G^*水平上优化了6种F,Cl和Br取代的咪唑衍生物分子几何构型,在此基础上采用TD-DFT的方法计算了它们的前线轨道能级和电子光谱,并用CPHF方法研究了此类衍生物二阶非线性光学系数性质.计算结果表明:此类化合物具有平面结构,共轭性较强;分子内设计的推拉电子基团增强分子内电荷转移,使前线分子轨道间的电子跃迁更容易;各体系具有较大的βvec和良好的透明性;咪唑环的引入增强了体系的热稳定性.弦些结论对分子设计具有一定的指导意义.

  • 标签: B3LYP方法 TD-DFT方法 咪唑类衍生物 电子光谱 非线性光学
  • 简介:6/3-(4-Chlorophenyl)-s-triazolo[3,4-b][1,3,4]thiadiazoles(2a-e)and(5a-e)weresynthesizedrespectivelybyintermolecularcyclizationof5-aryl/4-chlorophenyl-4-amino-3-mercapto-1,2,4-triazoles(1a-e)and(4)with4-chlorobenzoicacid/arylacids,whichwerecondensedwithpiperazineunderphasetransfercatalystTBABtoyieldthecorrespondingfreebasesofmonopiperazinederivativesandfollowedtoformwater-solublesalts(3a-e)and(6a-e)withhydrochloricacidingoodyields.Theinvitrobiologicalresultsshowedthatpiperazinegroupconjugatedwiththeabovefusedheterocyclesplayedanimportantroleinantibacterialactivity.ThestructuresofnovelcompoundswereconfirmedbyIR,1HNMR,MSandelementalanalysis.

  • 标签: 哌嗪 相转移 可溶性 抗菌活性 催化合成 药物
  • 简介:The2-C,methylenegroupof1-aroyl-1,2-dihydro-3H-naphtho[2,1-b]pyran-3-ones(2)havebeenshowedtopossessasuperiorreactivitytowardsmanyoforganicreagents.Thena-phthopyrones(2)condensedwitharomaticaldehydestogivethe2-arylidinederivatives(3).Bromin-ationof2gave1,2-dibromo(4)or5-bromo(5)derivativesdependingonthereactionconditions.Thebasecatalyzedadditionorcycloadditionofnaphthopyrones(2)to4-methoxybenzalacetophenonegavetheexpectedMichaeladduct(6)orthecyclicadducts(7-9)dependingonthetypeofcatalyticbaseandreactionconditions.Structuresoftheproductshavebeenestablishedbyelementalanalyses,IRand~1HNMRspectroscopicmethods.

  • 标签: PYRAN REACTIVITY aldehydes aromatic bromo catalyzed
  • 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.

  • 标签: 晶体结构 [1 3 4]噻二嗪 制备 光谱表征 Π-Π相互作用
  • 简介:8,8′-Dibromo-6,6′,7,7′-tetramethoxy-5,5′-diisopropyl-3,3′-oxydimethylenedinaphtho[2,1-b:2′,1′-d]furan,C32H30Br2O;M.W.=670;triclinic;spacegroupP1;a=8.896(2),b=10.216(1),c=10.423(1)A,α=108.48(1),β=119.36(1),γ=99.26(1);V=723.5A3;Z=1,Dcal.=1.479g.cm-3.MoKα=28.11cm-1,F(000)=326,T=293K.Thestructurewassolvedbydirectmethodandfull-matrixleast-squaresrefinementconvergedatR=0.034for2377observedreflections.Theoxygenatominseven-memberedringexistsinadisorderedarrangement.Bothbisnaphthaleneandoxygen-containingfive-memberedringhaveplanarconformationswithdihedralangle6°,showingmarkedaromaticfeature.

  • 标签: FURAN derivative dibromo-6 6 TRICLINIC membered planar
  • 简介:Halfsandwichirondicarbonylcomplex[η5-C5H3(t-Bu)2]Fe(CO)2Cl(1)reactswith1,2-dilithiumdiselenocarboraneLi2Se2C2B10H10(2)togiveabinuclearironcarboranecomplex[η5-C5H3(t-Bu)2]2Fe2(CO)3*Se2C2B10H10(3).TheX-raydiffractionanalysisofcomplex3revealsthatoneoftheironatomsischiral.

  • 标签: Carborane Halfsandwich IRON complex Chirality Molecular