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1.
IntroductionTheinnatecharacterofthesolidcarcinomaistheresultthatcellgrowthgetsoutofcontrol.Itsbasicreasonconsistsintheabnormalityofthetumorgene .SomeonethinksthatthegeneofIGF Ⅱisoneofthecancergenesofthe primaryhepatocellularcarcino ma[1] ,andalsothinkstheoverexpressionofthegeneofIGF Ⅱtakesplaceintheearlierperiodofthepri maryhepatocellularcarcinoma ,whichmaybetheear lierdiagnosticnormofprimaryhepatocellularcarcino ma .ThefurtherresearcheshavedemonstratedthattheactivationofIGF Ⅱ genepromo…  相似文献   

2.
IntrOduedon:ThemodPodedcattalcwegheqailtheelementsisPr~thatofge~Um,A.(Ge.~cuous~aslargaso.o4ekiStS~nthe~Ge)detenninedtymass~andthatfoundtytheclassitalchthetalInethod').ThePreSentinveedghonaimsatCarryinouathetutetheonmeasurmentusingthetrueisotwicbooofGa6,nl=l.5o676(39)fOundtyMachlanetaLinacali~tnass~cmecmenP,wherethevaluewithintbebracketsindibestheerrorofthelaStbodigitS.ooumandge~umareneighborsintheperiedcSystmQfelements.TheformrisbinpelidicandhasisotpewithmassnUmbosas69and71,whereas~u…  相似文献   

3.
Gossypol was obtained as an yellow platelike crystal with m.p. 210-214o . In CDCl3 there were three tautomers of gossypol: I aldehyde, II lactol,III ketal , in equilibrium .Their total H 1 NMR spectra were assigned by means of 1D and 2D NMR techniques including 1H-1H cosy , DEPT , HMQC (1H Detected Heteronuclear Multiple Quantum Coherence) and HMBC (1H Detected Heteronuclear Multiple Bond Connectivity) experiments . This paper first reported that we took use of the 2D NMR t…  相似文献   

4.
A pair of derivatives of tetrameric N-methylpyrrole polyamide were synthesized in order to develop a new method for the study of interaction of the polyamide derivatives with DNA. Indole acetic acid and nicotinic acid were introduced to the polyamide in the synthesized compound, which showed an expected red shift in the UV spectrum. These compounds may function as a potential tool in the detection of the polyamide binding to DNA.  相似文献   

5.
TheacetoneselfCImassspectrumAcetoneselfCImassspectrumisgiveninTable1.Table1.MajorproductionsandtheirrelativeabundanceofacetoneselfCIMSTheformationofionatmlZ73AnotherproductionintheselfCIMSofacetoneistheionatm/z73.InselfCIMSofacetone-d6,thecounterpartistheionatInjz82.InselfCIMSofthemixtureofacetoneandacetone-d6inaratioofl:l,thecorrespondingionsaretheionsatInlz73,76,79and82.TheirCIDreactionresultsarelistedinTable2.Table2.TheCIDMSoftheionatIn/z73andanalogsOnthebasisofthedatainTab…  相似文献   

6.
Phthalascidin is a structurally simplified version of Et-743, which is a potent anti-tumor marine natural product isolated from Ecteinascidia turbinata. Its antiproliferative activity is greater than that of the agents taxol, camptothecin, adriamycin, mitomycin C, cisplatin, bleomycin, and etoposide by 1-3 orders of magnitude. An elegant synthesis of Et-743 and phthalascidin has been reported by E. J. Corey and co-workers1,2. As part of our continuing program, we have also engaged in dev…  相似文献   

7.
ThedidenlnaketalsAandBhaveprovedtobesignificantinhibitorstoHIV-Iprotease'.UPtotilepresent.however,nosuccessfulsynthesishasbeenreported.Inconnectiollx'l,lthOLlrs}'ntheticstudiesoftheiranalogLles,wehavereportedasuccesslillsynthesisofthesimilarilltermediateof32.Hereinwewouldpresentanefficientprocedureforthediastereoselectivesynthesisofanotherintermediate4.Basedoiltileretrosyntheticanalysis,theintermediate4couldbesynthesizedfromllaturalI.-(-)-nlelltllollebecauseofthevaltlablechiralCSmethyl.…  相似文献   

8.
Thedevelopmentofmetallocenecatalystsundoubtedlyrepresentsarevolutioninthepolyolefinbusiness.MetallocenePE(MPE)coverspolyethyleneswhichareproducedbymetallocenecatalysttechnology.EXXONChemicalCo.developedanewmeta-llocenepolyethylene-EXCEED'"PEin1991.Nowmoreandmoreeffortsarespentonthisinterestingproject.Uniformmolecularstructureandnarrowmoleculardistribution,makeMPEbetterphysicalpropertiesthanthoseofconventionalPE,andalsomakeitlowmeltstrengthandbadprocessability.Sotherelationshipbetween…  相似文献   

9.
RemovalofalundnumfromNaYzeolitewithacidisanimportantprocessinthemodificationofzeolite.ItisdifficulttoremovealundnumfromNaYzeolitedirectlywithacidwhilekeepinghighcrystallinity.Intheworkreportedhere,alundnumisremoveddirectlyfromNaYwithoxalicacidandthemodifiedzeolitekeepshighcrystallinity.Reactionconditions:CSBlreflux,acidaddedin3ondn,allowedtoreactfor3OAnn.CSB2reflux,acidaddedrapidly,allowedtoreactfor3Owhn.CS2525-C,acidaddedraPidly,allowedtoreactfor3Omin.CSA25"C,acidaddedin3omin,a1lowe…  相似文献   

10.
SinceLatimerlproPosedthatthestandardentropiesofsolidcomPoundscanbeeshmatedbythesumofeachionicentropy,manyscholars13'4haveimProvedthismethod.Buttheyarestilllindtedbytalmer,sproposal.SincetheProPertiesofchendcalsarenotderiVedsimPlyfromthesummahonofindividualions,thissimPleadditivemethodisnotsatisfactorilyaccurate.Complexsilicatesareveryimportantformetallurgy,geologyandchemicaImaterial,sofindingmethodsforcalculatingstandardentropiesofcomplexsilicatesistheoreticallyandpracticallyimPortant.The…  相似文献   

11.
The kinetics of transformation of 1,3,4,7-tetramethylisoindole(1)to 1,3,4,7-tetramethyl-1H-isoindole(2)in water or in deuterium oxide at various pH or pD at 25℃ were measuredspectrophotometricalty.The results indicated that the transformation of 1 to 2 could be promotedby acid and base.From the solvent isotope effects and the fact that the 1-position of isoindole nucleusis electron-rich,the mechanism of this transformation is suggested.  相似文献   

12.
Losartan 1 (Dup-753) is a nonpeptide angiotensin II receptor (type AT1) antagonist discovered by Duncia, J.V. et al. 1 in 1990 and its potassium salt (cozaar) has been marketed as an antihypertensive since 1995 2. 1 2 Starting from Dup-753, a great number of structural related compounds have been prepared by several laboratories and several antihypertensive drugs have been developed3. In order to find new and more active compounds, a novel type of Losartan analogues 2 was designed and syn…  相似文献   

13.
Introduction:Aftergainingexperienceintheisotopicratiomeasurementofsamarium(1),weproceededtocarryoutaprecisedeterminationofitsatomicweightandobtainedavalueofA,(Sm)agreeingperfectlywiththatobservedbyLugmair<'>andWasserburg<'>.Sampleofsamarium:Asampleofsamarium,99+%Sm,O,,wassuppliedbytheResearchInstituteofRareEarths,NanchangUniversity,Jiangsi.Itwasextractedfromthemineral,rareearthadsorptionkaolinite,anextensivedepositintheprovince-Thematerialwasfurtherpurifiedbyextractionchromatographythrou…  相似文献   

14.
Synthesis and Crystal Structure of Nickel Complex of DSEN   总被引:2,自引:0,他引:2  
1INTRoDUCTIoNTheSchiffbasesareofgreatimportanceincoordinationchemistryasligands.TransitionmetalcomplexespreparedfromsalicylaldehydeSchiffbasespossessbiologi-calactivities[1~33.Forexample,Mn,Fe,Co,Ni,ZnandMoionsinproteincarryoxygen,transmitelectronandstoreprotein.Furthermore,manyofthiskindofcomplexescanalsobeusedashomogeneouscatalysts['~5i.WehavereportedthatSchiffbasespreparedbysalicylaldehydeandtriazolehavecatalyticactivitiesforsyn-thesizingethylenecarbonatet6).Forfurtherstudiesoftheca…  相似文献   

15.
lnthepreviouspaper',wereportedtheintramolecularcyclizationsofamide4anditscis-eneisomerinanattempttosynthesizehomoclausenamideandzetaclausenamide2.Inordertostudytherelationshipbetweenthestereochemistryandtheilltramolecularcyclizationofthisseriesofcompounds,theamides5(cis-oxirane,trans-ene)and8(cis-oxirane,cis-ene)wereprepared,andtheirintramolecularcyclizationswerereportedinthispaper.Theamide5withm.p.152.O-l54.O"CwasobtainedfromDarzen'scondensationofcompound3withPhCHOinMeOHatl5-2OoCwithMeO…  相似文献   

16.
For searching a better 4-aminosalicylic acid derivative with higher activity and less side effects against the inflammatory bowel disease, 4-aminosalicylic acid (4-ASA) was protected by benzyloxycarbonyl and acetyl, respectively. The resultant was hydrogenized to remove protective group of amino group, then the product was reacted with NaNO2 to give diazonium salt, which was conjugated with salicylic acid, hydroxybenzene, TV-salicyloyl glycine acid to get azo derivatives of 4-ASA. The azo derivatives were hydrolyzed under the alkaline condition to get the target products. All compounds were characterized by FT-IR, 1H NMR, 13C NMR spectra in details. New derivatives of 4-ASA were characterized. The synthetic route was reasonable and feasible.  相似文献   

17.
IntroductionSnake-cageresin,alsoca1ledsnake-cagepolyelectrolyte['],isaspecialkindofamphotericresin.ItwasfirstinvestigatedbyHatchM.J.etal.in1957[z].Thetypicalandusefulsnake-cageresinisRetardation11A-8(l1A-8inthecon-text)manufacturedbyDowChemicalCoI,TD.Itissynthesizedbypolymerizingacrylicacidinsidethenetworkofastrongbasicanionexchangeresinwith8%crosslinking.Thus,theresinconsistsofacrosslinkedpolymermatrix,cage,andalinearpolymer,socalledsnake,whichisphysicallytrappedinsidethecage.Thecagepol…  相似文献   

18.
A simple method has been developed to predict the calmodulin-binding domains of peptides and the affinities of the peptides for calmodulin based on a model for the calmodulin-binding domains of peptides proposed in a previous paper and the literature data of calmodulin-binding peptides. The effects of hydrophobitities, α-helix-forming tendencies, and basicities of peptides on their affinities for calmodulin were studied. Model peptides were designed to examine the calmodulin-binding domain model and the prediction method. The determined dissociation constants of the complexes formed from the model peptides and calmodulin are in good agreement with the predicted results.  相似文献   

19.
Four derivatives of 5,5',6,6'-tetrachlorobenzimidazolocarbocyanine iodide with different long alkyl chain substituents in N-position of polymethine chromophore have been used for investigating the influence of hydrophobicity of dyes on the aggregation.It has been found that all dyes formed monomeric species in methyl alcohol. However, after addition of water to CH_3OH to change the polarity of the solvent, difference between dyes appeared.Addition of inorganic salt facilitated the J-aggregation of easy soluble dye, but it seems useless for the sparely soluble dye.Platelets cut from AgBr polycrystal or pressed AgBr powder have been used as substrate for adsorbing dyes. After addition of hexanoic acid, eventually the J-aggregate on AgBr surface could be destroyed.Voltammetry is a useful tool to investigate the interaction between dyes and AgBr. Experimental results showed that the longer the carbon chain substituents is, the stronger the interaction between AgBr and dyes would be.  相似文献   

20.
Ironisoneofthefourteentypesofessentiallybiologi caltraceelements .Ironplaysanimportantroleinlivingbodyanditwasregardedastherequiredtraceelementforlife .Manystudiesindicatethatdeficiencyorexcessofironmaybethecauseofmanydiseases .Furthermore ,ironisactivecenterofpigmentoxidase ,andsuccinicdehydroge nase ,etc .Consequently ,thestudyoftheinfluenceofironanditscompoundsonmicroorganismissignificantforun derstandinglifephenomenon .1Inhibitoryorantibioticactionofpurpleacidphos phatases (PAPs)hasnotbe…  相似文献   

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