简介：借助于G03W程序包,对系列氨基羧酸分子的羰基铼配合物进行了结构优化,并对其中的相关能量、键长、键角、布局数等进行了研究.计算结果表明：各配合物相对于羰基铼中间体均具有一定的稳定性;配体分子结构中含有杂环或者较多数目杂原子时,有形成相对更稳定配合物的趋势;配体分子结构中应含有适宜的间隔体,否则需经较大的结构扭转或局部原子的拥挤方可形成相应配合物.

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

简介：Theorientationoftheadditionof5-amino-3-benzylthio-1,2,4-triazoleanditsanalogues(pyrazole)(1)withthearylisocyanatecanbedirectedbycontrollingthereactiontemperatureandoneoftheproduct,5-amino-1-arylaminocarbonyl-3-benzylthio-1,2,4-triazole(pyrazole)(2),canrearrangeat170Ctoanotherproduct,5-arylureylene-3-benzylthio-1,2,4-triazole(pyrazole)(3).Aplausiblemechanismexplanationforthisrearrangementreactionwaspresented.Itwassuggestedthattherearrangementreactioncouldbereferredtothethermodynamicstranspositionleadingtothepredominant5-arylureylene-3-benzylthio-1,2,4-triazoleenergypreferentially.

简介：Novelsulfur-containingcompounds(3a–3c,4a–4c)wereobtainedinethanolwith1,3-diphenyl-2-propanoneasthestartingmaterial.Theadvantagesofthisprocedureweremildreactionconditions,simpleprotocol,andhighyields.ThestructuresoftheproductswerecharacterizedbyIR,1HNMR,MSandelementaryanalysis.Thecrystalofthenewcompound4abelongstomonoclinic,spacegroupC2witha=18.727(3),b=6.5179(9),c=13.7576(18),b=131.0610(10)°,V=1266.2(3)A3,Z=2,Dc=2.136g/cm3,μ=1.078mm-1,F(000)=843,R=0.0490andwR=0.1247for3211observedreflectionwithI>2δ(I).X-rayanalysisrevealsthatthemoleculeisnotsymmetrical,themolecularstructureisstabilizedbyweakp–pstackinginteractions,andnoclassicalhydrogenbondscanbeobserved.

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.

简介：AnefficientroutetoprepareL-glucoseandL-galactoseisdescribed.TheL-sugarsareachievedbyusingthestrategyofswitchingthefunctionalgroupsatC1andC5ofD-glucoseandD-mannose.TheoxidationandreductionofthesilylenoletheratC1andthelead(IV)tetraacetatemediatedoxidativedecarboxylationatC5arethekeysteps.L-GlucoseandL-galactosearepreparedinaconvenientandinexpensiveway.

简介：Four1,2,3-trisubstitutedimidazoliniumiodideswhichwereusedas5,10-+CPh-THFmodel（7-10）atformicacidoxidationlevelweresynthesized.Thebenzylidynegroup（phenyl-substitutedonecarbonunit）transferreactionsfromthesecompoundstoGrignardreagentwerein-vestigated,andthereactionsofthesecompoundswithKBH4andNaOHwerealsostudied.

简介：NineteenL-N-2-hydroxyethylaminoacidsandL-N,N-bis(2-hydroxyethyl)aminoacidswerepreparedfromthereactionofchlorohydrinwithL-alanine,L-valine,L-leucine,L-isoleucine,L-phenylalanine,L-serine,L-thrcunine,L-glutamicacid,L-asparticacidandglycine.L-N,N,N’,N’-tetra(2-hydroxyethyl)cystinewaspreparedbythereactionofL-cystinewithchlorohydrin.

简介：本文通过电化学测量（循环伏安法）和量子化学计算（CNDO/2法）对几种原子簇化合物[（MoS4）2FeL]3-（其中配位体L为O2CH3CN,O2,O）的氧化还原活性进行了研究.实验测量与理论计算所得结果相符.研究结果表明这几种阴离子的还原皆为不可逆的单电子转移过程.它们接受电子的能力按如下次序递增:[（MoS4）2FeO2CH3CN]3-<[（MoS4）2FeO2]3-<[（MoS4）2FeO]3-

简介：Anewbiflavonoid,stelleranol,wasisolatedfromtherootsofStellerachamaejasmeL..ItsstructurewasdeterminedbytheanalysisofMSandNMRdata,especially2DNMRspectra.

简介：新奇sesquiterpenoid，pterisemipol，从PterissemipinnataL被孤立。它的骨骼，也就是pterisane，被认为从protoilludane被重排，它的结构根据分光镜的分析被阐明。

简介：Anewμ3-Otriiron（Ⅲ）complex[Fe3O（OBz）6（CH3OH）3]（NO3）（CH3OH）2（HOBZ=benzoicacid）hasbeensynthesized,itsstructurehasbeendeterminedandvariabletemperaturemagneticsusceptilityhasalsobeenmeasured.Inthemolecule,threeironatomsformedanequilateraltrianglewithu3-Oincenter.ThefittingtothemagneticsusceptibilityshowedthatanintramolecularantiferromagneticexchangeinteractionoccurredbetweenironatomswithJ=-25.51cm-1,andaweakerintermolecularantiferromagneticexchangeinteractionoccurredwithzJ’=-2.30cm-1.

简介：ByusingOH-terminatedpolyaryletherdendrimerandN-Fmoc-glycineasrawmaterials,thedendriticpolyarylether2-aminoacetate(G3-NH2)wassynthesizedviatwostepreactions.G3-NH2asamacroinitiatorforthering-openingpolymerizationofγ-benzylL-glutamateN-carboxyanhydridewasinvestigated.Itisfoundthattheresultingcopolymerspossessedrelativelyhighmolecularweightandnarrowmolecularweightdistribution(1.12

简介：ConformationofL-lysineinaqueoussolutionwasinvestigatedbylanthanideshiftprobes（Dy,Ho,Er,TmandYb）.Reilley’smethodwasemployedtoseparatethecontactanddipolarcom-ponentsofthe13Cparamagneticshifts.ThisstudyrevealsthatCαshifthasthelargestcontactcon-tributionwhiletheothercarbonshiftsaredominatedbythedipolarcontribution.TheaverageoverallconformationofL-lysineinaqueoussolutionisextendedwiththemolecularbackboneintransform.Inthecomplex,lanthanideioncoordinatestothecarboxylgroupwithLn—Obondlength2.2/nandthewholeligandislocatedoutsidethezero-dipolarshiftconeofthelanthanideion.Theelectronicspindensitydistributionontheligandnucleishowsthatthespinpolarizationisthepredominantmech-anismofthecontactinteractionfornucleiincloseproximitytotheboundlanthanideion.

简介：ThesolidcomplexesofCr(AA)2Cl3·nH2OofCrCl3withL-α-aminoacids(AA=Val,Len,Thr,Met,Arg,Phe,TryandHis)havebeenpreparedin95?EtOHmedium,andcharacterizedstructurallybyelementalanalysis,chemicalanalysis,IRspectraandTG-DTG.Theconstant-volumecombustionenergiesofthecomplexeshavebeendetermimedbyRBC-Ⅱtyperotating-bombcalorimeter.Thestandardenthalpiesofformationofthecomplexeshavebeencalculatedaswell,hwichare(-2543.16±3.71)(Val),(-2561.32±4.06)(Leu),(-2284.02±2.95)(Thr),(-1418.77±4.60)(Met(,(-3218.91±4.67)(Arg),(-2643.90±5.02)(Phe),(-1707.18±3.23)(Try)and(-2838.05±3.45)(His)kJ/mol,respectively.

简介：Europium（Ⅲ）-dopedYF3ispreparedbyahydrothermalprocessat200℃.X-raydiffraction（XRD）patternidentifiestheformationofYF3phasewithoutdetectableimpurity.Environmentscanningelectronmicroscopy（ESEM）imageshowstheevensizedistributionofthesampleswithcubicmorphology.TheexcitationandemissionspectraoftherareearthionsdopedYF3areinvestigatedbyfluorescencespectrophotometer.Theexcitationspectrumfor591nmemissionhasseveralexcitationbandsat320,365,386,397and467nm,andthemainpeakvaluewas397nm.TypicalEu3+emissionpeaksat591nm（5D0→7F1）and612nm（5D0→7F2）areobservedwhenexcitedby397nm,andthestrongestemissionis591nm,demonstratingthattherareearthionsoccupythecentrosymmetricalsitesinYF3.

简介：[Co3(1,2-S2C6H4)3(PPh3)3][CoBr3(DMF)].sol(1,sol=CHCl3,O(C2H5)2,H2O)wasobtainedfromthereactionofCoBr(PPh3)3withNa2(S2C6H4)inchloroform.TheCo3coreinthecationof1exhibitsametal-metalbondedisoscelestriangle,inwhichthetwolongerCo-CobondsarebothbridgedbyS2C6H4ligandsontwosidesofthetriangleplanerespectively,whilethebottomshortCo-CobondisbridgedbythethirdbidentateS2C6H4ligand.Aseriesofpolynu-clearcobaltclustercompoundswithphosphine,thiolateand/orsulphurligandswerepreparedbylowoxidationstateCo+withthiolatesinorganicsolvents.Thesetri-,tetra-,hexa-,heptanuclearclustercompounds1-8withvarioustypesofcrystalstructurescanbeviewedasthecondensedpolynuclearcobaltcomplexesthatthecobaltatomframeworkswithsulphurbridgedwerebuiltthroughthesmalltriangularunitsof[Co3S3nL3](n=1,2)withorwithout[CoL](L=PR3,Br,Cl,5-C5H5)fragments.

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简介：Reactionsofthe6-hydroxy-thiopyrano[3,4-c]pyridine-5-carbonitrilederivative1withα-halo-carbonylcompoundsgavetheortho-substitutedintermediates2a-cwhichwereconvertedintofuro[2,3-b]thiopyrano[4,3-d]pyridines3a-cbyfusionofafuranmoietyunderbasicconditions.Furthercyclizationof3a-cledtoafusionofapyrimidinering,yieldingthetetracyclicproducts6,7and8.Inaddition,condensationof6withvariousaromaticaldehydesaffordedthecorrespondingimines9a,b.Mannichreactionof7gaveproducts10a,b.

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