简介：(-)-(5R,6S)-6-Acetoxyhexadecan-5-olide1,anaturalmosquitoattractantpheromone,wassynthesizedfromreadilyavailablealdehyde2andcyclopentanone3usingL-proline-catalyzedasymmetricaldolreactionasthekeystep.

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简介：Thesynthesisof(S)-2-(3-arylacrylamido)-3-{4-[2-(5-methyl-2-phenyloxazol-4-yl)ethoxy]phenyl}propanoicacidsisdescribed.TheirstructureswereconfirmedbyH-NMR.

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简介：利用Gaussian-94计算程序中的B3LYP方法,在6-311+G(2d)6d基组下,对Si5,Si5H3,Si5H6,Si5Li3和Si5Na3原子簇的几何结构进行优化和频率计算.结果表明,Si5原子簇中最稳定的具有D3h对称性的结构中,位于同一平面上的3个Si原子确实具有剩余的成键能力,可以与3个H,Li,Na原子和6个H原子形成稳定的化合物.研究还发现,虽然H,Li和Na都属同一主族,但它们与Si5原子簇中Si原子的键连方式却不同,而且它们的加入,对Si5原子簇的'三角双锥'结构也有不同的影响.

简介：神经生长禁止的因素(GIF)，metallothionein家庭的一个成员(metallothionein-3，MT3)，由它的不同神经生长众所周知禁止的活动，它没被另外的MTisoforms显示出。到现在为止，然而，人们仍然不清楚地知道GIF怎么施加它的生物功能。因为GIF力量用作没有scavenger，这被报导了并且与锌的版本有关，我们的学习被与没有施主的SNOCa类型学习人的GIF和人的MT1g的反应集中于GIF和号码的相互作用，GIF是比向SNOC的MT-1g更反应的，这被发现。为了进一步弄明白，如果在这反应的GIF的高反应源于酸硷的催化作用，几异种被构造：E23K，E41G/E43A，E23K/E41G/E43A。由向SNOC学习他们的基本性质和反应，GIF的S-nitrosylation与酸硷的催化作用有关，这被发现不仅，而且到metal-thiolate簇的可接近性。

简介：AhighlyefficienttotalsynthesisofS-(+)-tylophorinehasbeenaccomplishedinfullyasymmetricfashion.

简介：AF-5wassynthesizedthroughaconvergentmethod.ThekeystepwastheRobinsonannulationusingakeyintermediatepentylvinylketone.

简介：Tris)(η5-cyclopentadienyl-μ-carbonyl-iron)-μ3-nitrosylclusterwasobtainedfromthereactionofcyclopentadienyldicarbonylirondimerwithnitrogenmonoxideinxylene.Theclusterwascharacterizedbyelementalanalyses,IR,MSand1HNMR.Thecrystalstructureof[(η5-C5H5)(μ-CO)Fe]3(μ3-NO).C4H8OwasdeterminedbyX-raydiffractionanalysis.ItcrystallizesintheorthorhombicspacegroupPnma,a=9.053(2),6=10.545(2),c=22.525(4)A,V=2150.3(7)A3,Z=4,Dc=1.68g.cm-3;structuresolutionandrefinementbasedon1141reflectionswithI>3.0(I)(MoKa,A=0.71073A)convergedatR=0.0540.Theinfraredabsorptionbandat1325cm-1oftheμ3-NOinthecluster,whichisredshifted,showsthatμ3-NOisactivated.

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简介：INthepreviouspapersoftheauthor’s,theelementaryreactionoperatorconcerningpointgroupwasdiscussed.Inthispaper,morecomplexreactionoperatorswillbeanalysed.Byusingtheskillinreactionoperator,theelectrocyclicandcy-cloadditionreactionsareillustrated.

简介：Baker'syeastmediatedreductionofopticallyactivediketoneisdescribed.Thetwoketogroupsareefficientlydifferentiatedandtheeevalueoftherecoveredmaterialisconsiderablyraised.Itaffordshighlyopticallyactivekeyintermediatesefficientlyforthesynthesisofnaturalpolyhydroxylatedagarofuranproducts.

简介：TwonewcoenzymeB12analogues,2’,5’-dideoxycytidylcobalamin(2a)and2’,5’-dide-oxyuridinylcobalamin(2b),andtwoothers,2’,5’-dideoxyadenosylcobalamin(2c),and5’-deoxy-thymidylcobalamin(2d)werepreparedbyanimprovedmethod.AllthefouranalogueswereinvestigatedbyUV-visand2D1HNMRspectroscopy.Thecomparisonsanddiscussionabouttheirspectroscopicpropertiesweredone.

简介：(±)-5,5'-Dihydroxy-7,7'-dimethoxy-8,8'-biflavone((±)-l)wasresolvedintoitsopti-callypureformsviatheformationandrecrystallizationofits(2R)-and(2S)-l-(4-toluenesulfonyl)proly-late,andthemethylatedderivativesof(+)-and(-)-lwerealsoprepared.Theabsoluteconfigurationsofallthese8,8'-biflavoneshavebeenconfirmedbytheirCDspectra.

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.

简介：到HOCN的HNCO的反应，到HSCN的HNCS和到HSeCN的HNCSe在MP2/6-311++G被学习了(2df，pd)//B3LYP/6-311++G(2df，pd)水平。反应物，转变状态和产品的几何学被优化了，转变状态的几何学第一次被报导。HNCO和HNCS容易被检测而不是HOCN和HSCN的原因被解释了。HNCSe将更容易比HSeCN被检测，这被预言。在反应的化学契约的破裂和形成被电子密度的拓扑的分析方法讨论了。在反应有二种结构转变状态(圣)的计算结果表演学习了。

简介：Fourteennew1-acyl-5-arylbiuretsweresynthesizedbythereactionofarylureaswithacylisocynantes.Thelatterwasobtainedfromacylchlorideandleadcyanateindichloromethane,usingpyridineascatalyst.Thestructuresofcompounds3a-nwereconfirmedbyIR,1HNMRandMSspectra.

简介：Treatmentof4-amino-3-(1-aryl-5-methyl-1,2,3-triazol-4-yl)-5-mercapto-1,2,4-triazoles/2-amino-5-(1-aryl-5-methyl-1,2,3-triazole-4-yl)-1,3,4-thiadiazoleswithbenzaldehyde,acetoneandω-bromoacetophenonewastestedandcompared.ThetitlecompoundsSchiffbases,amides,imidazolo[2,1-b]-1,3,4-thiadiazolesand7H-s-triazolo[3,4-b]-1,3,4-thiadiazineshavebeenconfirmedbyelementalanalyses,^1HNMR,IRandMSspectra.AllthecompoundshavealsobeenscreenedfortheirantibacterialactivitiesagainstB.subtilis,S.aureusandE.coli.

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简介：Achiralrutheniumcomplex[(1S,2S)-DPEN]-RuCl_2(PPh_3)_2(DPEN=1,2-diphenylethylenediamine,PPh_3=triphenylphosphine)wasencapsulatedinthechannelofAl-MCM-41byelectrostaticadsorptionand1,1-dichlorosilacyclobutanemodification.Thepreparedheterogeneouscatalystshowedthesamecatalyticactivityandenantioselectivityasthecorrespondinghomogeneouscatalystintheasymmetrichydrogenationofacetophenone,andcouldbereusedatleastseventimeswithoutsignificantlossofcatalyticactivityandenantioselectivity.