简介: Enantioimericallypure1,l'-bi-2-naphthol(BINOL)1anditsderivativesareimportantchiralligandsandauxiliariesforanumberofasymmetrictransformations1suchasaldolcondensations,alkylations,Diels-Alderreactions,Michaeladditions,epoxidations,etc.Opticallypure1andtheirderivativeshavealsobeenusedextensivelyinchiralrecognition,chiralseparationandintheconstructionoffunctionalisedmaterials2.Furthermore,(R)-and(S)-BINOLarealsofundamentalstartingmaterialsforthesynthesisofalargevarietyofotherchiralbinaphthylssuchasMOP(2c),NOBIN(2d)andBINAP(2e).Asaresultthedevelopmentofefficientandeconomicmethodsforthepreparationofopticallypure1hasattractedmuchattentioninrecentyears3andnovelmethodsfortheresolutionof(±)-1continuetobedeveloped.……
简介:在新头孢霉菌素药和papain的二第4产生之间的相互作用在不同温度通过光谱学方法被学习。他们的分离常数被分别地,使用熄灭的荧光和荧光改进的理论公式和他们的相应热力学的功能计算,偶极子偶极子非放射的energy-transfer-efficiency和领受人底层等等的行动距离进一步被计算。分析揭示那,由cefpirome和cefepime在papain上熄灭是基本上由于在施主和领受人之间的偶极子偶极子非放射精力转移和某些动态碰撞,在药和papain之间的相互作用主要是恐水病的它可以在papain上为药理学和新陈代谢的学习提供有用信息。在这纸荧光,熄灭被认为是否定荧光改进,和荧光熄灭的二种理论公式,荧光改进被用来计算荧光熄灭一样的批,和很靠近的结果的试验性的数据被获得但是与某些差别。结果当对待领受人底层行动时,不仅显示二个理论方程的等价,而且证明基于荧光的理论公式,改进(4)被我们推出,是的热力学的数据更合理。我们因此甚至在学习在受体底层之间熄灭的荧光的过程建议那,用荧光改进(4)的理论公式能得到更可靠的结果。
简介:Auranylcompound,K4UO2(CO3)3hasbeencharacterizedbypowderX-raydiffractionmethod.M.W.=606.46,monoclinic,C2/c(No.15),a=1.0240(7),b=0.9198(4),c=1.2222(12)nm,β=95.12(4)°,V=1.1466(5)nm3,Z=4,Dm=3.468g/cm3,Dc=3.513g/cm,λ(CuKα1)=O.1540598nm,T=298K.ThestructurewassolvedbyheavyatommethodandFouriersynthesis,andrefinedbyfull-matrixleast-squaresmethodtoR=0.1185for275reflections.Theuranium(Ⅵ)atomisinaneight-coordinatedistortedhexagonal-bipyramidalenvironmentwithcreasyfanshape.Thelinearuranylgroupapproachestoperpendiculartotheequatorialplaneinwhichthreecarbonategroupsarechelated.U(Ⅵ)hastwolinearoxygenatomsclosertoit(U-O=0.1767(5)nm)thansixotherneighbours(U-Orangingfrom0.2516to0.2568nm).Thedistancesbetweencarbonatomsanduncoordinatedoxygenatomsare0.122(1)and0.123(1)nm,whicharedistinctlydifferentfromthosebetweencarbonandcoordinatedoxygenatoms(mean0.134(6)nm).Thisfactrevealsthenon-eq-uivalenceofoneoxygenatomtotheothertwoineachcarbonate.InK4UO2(CO3)3,theO-Odis-tancefortheadjacentcarbonategroupsis0.2794(4)nmapproachingtothesumofVanderWaalsradiioftwooxygenatoms.TheK-Odistancesvarybetween0.2667and0.3131nm,andeachanionisimmediatelysurroundedbysixpotassiumions,onlyfourofwhichcanbeconsideredtobelongtothesamestructuralformulaunit,andtheyaresymmetricallylocatedaboveandbelowtheequatorialplane.
简介:AnHPLCmethodforquantitativedeterminationofadrenalinehydrochlorideinjectionandnoradrenalinebitartrateinjectionwasestablishedandvalidatedwithasubstituteforthereferencesubstance.Phenylephrinehydrochloridewasselectedasthesubstituteforthereferencesubstanceofadrenalineandnoradrenalinebitartrate.Thecorrectionfactorofphenylephrinehydrochloridewithrespecttothereferencesubstanceofadrenalineandnoradrenalinebitartratewasdeterminedunderdefinedconditions.Adrenalinehydrochlorideinjectionandnoradrenalinebitartrateinjectionwerequantifiedbyassayingphenylephrinehydrochlorideandacorrectfactor.TheresultsindicatethattheHPLCmethodwiththesubstituteforreferencesubstancewasreliableandfeasibleforquantitativedeterminationofdrugs.
简介:在这个工作,二个chemometrics方法被申请建模和一些器官、无机的混合物的electrophoretic活动性的预言。连续设计算法,特征选择(矿泉)策略,被用作描述符选择和模型发展方法。然后,支持向量机器(SVM)和多重线性回归(MLR)当模特儿被利用构造非线性、线性的量的structureproperty关系模型。用SVM模型获得的结果与用MLR获得的那些相比表明SVM模型比MLR那个具有更好预兆的价值。分别地,当时,为训练集合的root-mean-square错误和为SVM模型的测试集合是0.1911和0.2569由MLR模型,他们分别地是0.4908和0.6494。结果证明SVM模型急速地在QSPR研究提高预言的能力并且比MLR模型优异。
简介:Thegeometricalstructuresof2-(2-hydroxyphenyl)pyridine(PP)anditsprotonationstateswereoptimizedbymeansoftheB3LYP/6-31G(d)method.Foralltheselectedsystems,theexistenceofH-bondisinfavorofthestabilityofthesystems.Onthebasisoftheoptimizedgeometricalstructures,theirelectronicspectrumpropertieswerestudiedbytime-dependentdensityfunctionaltheory(TD-DFT)methosdviaahybridfunctionofB3LYPand6-31G(d)basisset.TheTD-DFTcalculationresultpredictstheabsorptionspectrumofPPat324nm(3.82eV),whichisinverygoodagreementwiththeexperimentalvalueof322nm(3.85eV)determinedinsolventchloroform.TheabsorptionspectraofthetwoprotonationstatesbothexertaredshiftinvariouspHmedia.
简介:为单个核苷酸多型性(SNP)的当前的方法分析消费aretime并且复杂。我们为快速的SNP分析在一步舞的开发瞄准了即时fluorescencemutant-allele-specific扩大(MASA)方法。方法是二种技术的婚姻:为目标脱氧核糖核酸和双stranded的MASA教材DNA选择的荧光染料,格林·西布尔I.Genotypes根据thewild类型的不同阀值周期被分开,变异的primers.K地岬oncogene被用作一个目标验证不同遗传型能清楚地是,这试金区别的试验性的结果显示出的themethod.The的可行性。即时荧光MASA方法将由于它的简洁和低费用为快、可靠的SNP分析有一个庞大的潜力。
简介:SimultaneousBiparametricDeterminationofTotalCalciumandPotassiuminBiologicalFluidsbyFlowInjectionAnalysis──UseofPowell'sMethod...
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简介:Thethree-phasesbehaviorinthequaternarystsemofn-dodecylpolyglucosideC12G1.46/1-butanol/cyclohexane/waterhasbeenstudiedat40℃intermsofthevariablesγandδ.Increasingδatconstantγcausesaphaseinversionfromanoil-in-watermicroemulsionincontactwithexcessoil(winsorIor2)toawater-in-oilmicroemulsionincontactwithexcesswater(winsorⅡor2)viaamiddle-phasemicroemulsionincontactwithexcessoilandwater(winsorⅢor3).Bytakingintoaccountthedifferentsolubilitiesofalkylpolyglucosideand1-butanolintheoilphase,thecompositionofthehydrophile-lipophilebalancedinterfacialfilminthemiddleofthethree-phasebodycanbecalculated.Theeffectsofdifferentoilsandaqueousmediaonthephasebehaviorandonthecompositionoftheinterfacialfilmandtheefficiencyforalkylpolyglucosidetomakeequalweightsofwaterandoiltoasinglephasewereinvestigated.Itwasfoundthattheoilmoleculeswithsmallmolecularvolumescanimprovethesolubilizingefficiencyofthesurfactanttoformsingle-phasemicroemulsion.Ininorganicsalt(NaCl)andacid(HCl)solutions,less1-butanolisneededthanthatinalkali(NaOH)solutiontoformmiddle-phasemicroemulsion.