简介:Comparativemolecularfieldanalysis(CoMFA),athreedimensionalquantitativestructure-activityrelationship(3D-QSAR)methodwasappliedtoaseriesofdiindolylmethane(DIM)analogstostudytherelationshipbetweentheirstructureandtheirinductionofCYP1A1-associatedethoxyresorufin-O-deethylase(EROD)activity.ADISCOmodelofpharmacophorewasdervedtoguidethesuperpositionofthecompounds.Thecoefficientofcross-validation(q^2)andnoncross-validation(r^2)forthemodelestablishedbythestudyare0.827and0.988respectively,thevalueofvarianceratio(F)is103.53andstandarderrorestimate(SEE)is0.044.ThesevaluesindicatethattheCoMFAmodelderivedissignificantandmighthaveagoodpredictionforthecatalyticactivityofDIMcompounds.Asaconsequence,thepredictedactivityvaluesofnewdesignedcompoundswereallhigherthanthatofthereportedvalue.
简介:Thethermalbehavior,mechanismandkineticparametersoftheexothermicdecompositionreactionof3,3-bis(azidomethyl)oxetane/tetrahydrofuran(BAMO/THF)copolymerinamodehavebeeninvestigatedbymeansofDSC,TG-DTG,fastandlowerthermolysis/FrIRandTG-MS.Thereactionmechanismwasproposed.Theapparentactivationenergyandpre-exponentialconstantofexothermicdecompositionreactionofthecompoundat0.1MPaare167.04kJ·mol^-1and10^14.41s^-1,respectively.ThecorrespondingcriticaltemperaturesofthermalexplosionobtainedfromtheonsettemperatureTeandthepeaktemperatureTpare223.20and245.78℃,respectively.ThekineticequationoftheexothermicdecompositionprocessofBAMO/THFat0.1MPacouldbeexpressedas:dα/dT=10^15.19[-ln(1-α)^2/3e^-2.009×10^4/T
简介:Onenewsesquiterpenecompound,namely,illihenlactoneA(1),andonenewprenylatedC6–C3compound,illihenryioneH(2),alongwiththreeknownsesquiterpenes(3–5)wereisolatedfromthestemsofIlliciumhenryi.Thestructuresof1and2wereelucidatedbyspectroscopicevidenceincludingNMR,HRESIMSandcirculardichroism(CD).Compound2exhibitedaweakinhibitoryratioforbglucuronidasereleaseinducedbyplatelet-activatingfactor(PAF)inratpolymorphonuclearleukocytes(PMNs)invitro.
简介:Lophenol,cholest-4α-methyl-7-en-3β-ol(1),obtainedfromDracaenacochinchinensis(Lour.)S.C.Chen,wasstructurallymodified.Itwasacetylatedtoprotect3β-hydroxylgroup,andthenoxidisedbyseleniumdioxideinaceticacidtogivecholest-4a-methyl-8-en-3β,Ta-dioldiacetate(3).Thiscompound3isunstableinchloroformsolutionorwhenheatedandeasilyconvertedtoadienecompound,cholest-4a-methyl-7,14-dien-3β-olacetate(4).Thestructuresof3and4wereelucidatedbymeansofIR,^1HNMR,^13CNMRandMS,andtheabsoluteconfigurationof3wasestablishedbyX-raycrystallography.Thepropertyof3wasalsodiscussedinthispaper.Both3and4arenewcompoundsandwerereportedforthefirsttime.
简介:Sumoylationisanimportantproteinmodificationdiscoveredrecently.SUMO(smallubiquitin-relatedmodifier)pathwayregulatestheproteinstabilityandtranscriptionalactivitywitha12-kDasmallmolecularprotein,SUMO,ligatedtothetargetprotein.ThepurificationofSUMOproteinsisakeysteptorevealtheirfunction.ThepurposeofthisstudywastoconstructtherecombinantSUMO1geneclonedtoapGEX-4T-1vectortoexpressandpurifytheSUMO1-GSTfusionproteininEscherichiacoli.First,thefulllengthDNAsequenceofSUMO1genewasamplifiedbyPCRandwasligatedtopMD18-Tvector.ThentheSUMO1genewassubclonedtopGEX-4T-1prokaryoticexpressionvectorbetweenBamHIandXhoIsites,andtransformedinEscherichiacoliDH5αcells.Therightcolonieswereidentifiedbyrestrictiveenzymedigestionandsequencing.ThecorrectrebombinantplasmidofpGEX-4T-1-SUMO1wastransformedinEscherichiacoliBL21cellsandtheninducedbyIPTG(isopropyl-β-D-1-thiogalacto-pyranoside)toexpresstheSUMO1-GSTfusionprotein.ThehighlypurifiedSUMO1-GST(glutathioneS-transferase)fusionproteinwasobtainedbyaffinitychromatography.Finally,thepropertiesofSUMO1-GSTfusionproteinwereconfirmedbyCoomassiebrilliantbluestrainandWesternblotanalysis.TherecombinantplasmidofpGEX-4T-1-SUMO1wassuccessfullyconstructed,andSUMO1-GSTfusionproteinsweresuccessfullyexpressed.
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简介:Fe2O3solwiththeparticlediameterof3-5nmwasflocculatedbytheadditionofSDS,andtheflocculateformedwasredispersedbythefurtheradditionofthatsurfactant.ThusthesurfactantbilayerwasformedonthesurfaceofFe2O3.Theemulsionpolymerizationofstyrene(St)adsolubilizedonthesurfactantadsorbedbilayerwascarriedoutbyinitiatorpotassiumpersulfate(KPS).TheUV-Visandsurfacephotovoltagespectra(SPS)indicatethattheFe2O3particleswereencapsulatedinpolystyrene(PSt)successfully.