A New Spirostanol Saponin from Allium Chinense

AlIiumchinenseG.Don(liliaceae)isoneoftheoriginaiplantsofedonalCbineSmedicineMXiebai~,whichdistributesmainlyinSouthChinal].twensaPoninshave~beenisolatedfromthebulbsofthisplanbyourWot.InthisPape,werePorttheStrUCtUrehicitalonofanewspiroStanlSaPonin,medchinenosideW.ChinenosideVI,aInwiouspOWder,mP2l9-22lC,wasPOsitivetobOthLiebennannBurchardandMolishtests.InIRspeCtrUIn,y[possessedabsorptionbandsat3423(OH),2933,l7o2(C=o),l38o,lo49(C-o),andspiroStanolSaPonin'scharacteristicabsorption…     

A New Glucoside from Ceratostigma willmottianum

CeratostigmawillmottianumStapf(Plumbaginaceae)isaperennialherbdistributedinYunnanprovinceofChina.Thewhoieherbisusedasafolkmedicinetotreatrheumatism,traumaticinjuryandparotitis.ItschemicalcomponentShasnotbeenresearchedbefore.CeratosideA(I),CI,H22O,(HRMS,M-l62,found2o8.724,requires2o8.732),wasisoIatedasanamorphouspowder.ThemassspectrUmoflshowedaweakmolecularionatm/z37OandtWomajorionsatm/z2O8andl9Ob}'lossesof162andl8omassunitsrespectiveIyfromthemolecularion,inferringthepresenceofahoxose…     

A Simple and Efficient Procedure for the Preparation of O-aryl-O-ethyl-S-allyl Thiolophosphates

HubeiNaturalScienceFoundationforfinancialsupportChap-cyethy-S-allylthiOlwioSPhates(2a-j)havePOtenhalbiologicalachvihes.Inl983,Y.TamaruandZYoshidarePOrtedPallatuxn(o)catalyZedthiono-ffooloallylicrearr~mentOfcrallylphoSPhoro-andphoSPhonotheonaes,andaiSOreinvestigaedthennalrearrangementOfa-andy-methallyldiethyphOSPhorothionaesinrelallontotheregioselectivityObserVedinthePalladium(O)catalySisl'].InourPreviousStUdy,Hg(II)catalghcandthermalffoono-ffoolorearrangmentOfcrPrOPargylcreqlp…     

A New Method to Investigate the Clustering Phenomena in Supercritical Fluids

EstimationoflocaldensityofsolventaboutthesoluteSolvatochromicbehaviorsofspectroscopicprobesarewidelyusedtoestimatethesol-ventstrengthofsupercriticalfluids(SCF,).i-3lnthiswork,thesolvatochrondcshiftofthen-n*transitionbandforacetone(O.o37mo1.L-')insupercrihcal(SC)CO2wasde-terminedbyUVspectroscopytostUdythesolvationeffect.TheMcRae-BaylissexpressionbasedonthedielectriccontinUUInmodelgivestherelahonshipbetWeenso1vatochromicshiftandpo1arizabilityofnonPolarsolvents4-5asfollows:wherevisthewave…     

A New Route for Synthesis of Entecavir

2-Amino-1,9-dihydro-9-[(1S,3R,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopen tyl]-6H-purin-6-one (entecavir, Scheme 1) is a novel carbocyclic 2-deoxyguanosine analog drug which has potent and selective anti hepatitis B virus (HBV) activity1-3. Entecavir is also effective against lamivudine-resistant YMDD mutants4. The US Food and Drug Administration (FDA) approved entecavir as a new preferred drug for the treatment of HBV after lamivudine in March, 2005. Scheme 1 The structure o…     

A new phenylethanoid glycoside from Rabdosia lophanthoides （Buch.-Ham.ex D.Don） Hara.

A new phenylethanoid glycoside,3-hydroxy-4-methoxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(1→3)-2-O-acetyl-O-β-D-glucopyranoside, named lophanthoside A,was isolated from Rabdosia lophanthoides(Buch.-Ham.ex D.Don) Hara.Its structure was determined by spectroscopic evidences.     

STRUCTURE OF VERSICOLACTONE A,A NOVEL SESQUITERPENE LACTONE FROM ARISTOLOCHIA VERSICOLAR S.M.HWANG

A novel sesquiterpene tactone,versicolactone A,with 12-carbonring skeleton,has been isolated from the roots of Aristolochia versicolarS.M.Hwang,and the structure was elucidated on the basis of 2D NMR and MSspectral data.     

RECIPROCAL A.C.OSCILLOPOLAROGRAM

In this paper a new electrochemical method“Reciprocal a.c.oscillololarography”is discussed.Both principle and experimental work aredescribed.     

A STUDY OF PHOTOELECTROCHEMICAL CELLS BASED ON SILICON ELECTRODES COATED WITH METAL LAYERS

Photoelectrochemicat cells,composed of different epitaxial n-Si photoele trodescoated with metal such as nickel o platinum and immersed in a solution of redox couple BrBr_2 or Fe(CN)_6~(4- 3-),are investigated.A high conversion efficiency from optical to electri-cal energy up to 13.6% can be achieved under optimum conditions.     

A NEW GUANIDINE DERIVATIVE FROM ASTRAGALUS COMPLANATUS R.Br.

A new guanidine derivative,complanatin has been isolated from the seedsof Chinese traditional medicine Astragalus complanatus R.Br..Its structure wasestablished on the basis of spectral data and X-ray crystallographic analysis to beN-[3-carboxypropyl]-N-[3-methyl-2-butenyl]guanidine.     

C.A.期索引的作者索引之沿革

《化学通报》1985年第3期尚克聪同志的《C.A.索引图表分析》,在“C.A.索引一览表”里提到,C.A.期作者索弓以1958年Vol.52创刊延续至今。这似与,事实不符。 C.A.从创刊起就有了期作者索引。1907年Vol.1No.1至1908年 Vol.2 No.9,在每期文摘正文前,有“Name Register”,其作用和著录格式,与后来的期作者索引完全相同。同年No.10,这部分内容更名为“Au-     

A New Triterpenoid Saponin from the Seeds of Deccaria segetalis

The seeds of Vaccaria segetalis (Neck) Garcke, which is distributed all over China,except southern China, are used in Chinese folk medicine for promoting diuresis,activating blood circulation and relieving carbuncles 1. Previous studies on the seeds ofthis plant have led to the isolation of seven cyclic peptides 2-5 and several saponins 6-]o.We have repoyted the isolation and structural elucidation of Segetosides A, C-E from theseeds of Vaccaria segetalis I I-13. FuFther investigation of…     

C.A.索引图表分析

一、C.A.有哪些索引美国《化学文摘》(Chemical Abstracts——C.A.)从1907年创刊至今七十余年,索引从少到多,从简单     

改进的离子色谱系统监测重庆嘉陵江水质（英文）

The w ater quality monitoring operation to evaluate the w ater quality of polluted river is an extremely im po rtant task fo r the river-w atershed m anagem ent/co ntro l based o n the enviro nm ental po licy.In this study,the no vel,sim ple and co nvenient w ater quality m o nito ring o f Jialing-River in Cho ngqing,China w as carried o ut using an advanced io n chro m ato graphy(IC) co nsisting o f io n-ex clusio n/catio n-ex change chro m ato graphy(IEC/CEC) with conductivity detection for determining simultaneously the common anions such as SO 2 4,Cl,and NO 3 and the catio ns such as Na +,NH + 4,K +,Mg 2 +,and Ca 2 +,the ion-exclusion chromatography(IEC) w ith visible detectio n fo r determ ining sim ultaneo usly the nutrient co m po nents such as pho sphate and silicate io ns,and the IEC w ith the enhanced co nductivity detectio n using a po st co lum n o f K +-fo rm catio n-ex change resin fo r determ ining HCO 3-alkalinity as an ino rganic-carbo n so urce fo r bio m ass synthesis in bio lo gical reactio n pro cess under the aero bic co nditio ns.Acco rding to the io nic balance theo ry betw een the to tal equivalent co ncentratio ns o f anio ns and catio ns,the w ater quality evaluatio n o f the Jialing-River w aters taking at different sam pling sites in Cho ngqing m etro po litan area w as carried o ut using the advanced IC system.As a result,the effectiveness o f this no vel w ater quality m o nito ring m etho do lo gy using the IC system w as dem o nstrated o n the several practical applicatio ns to a typical bio lo gical sew age treatm ent plant o n Jialing-River o f Cho ngqing.     

A New Cyclopeptide from Brachystemma calycinum

Bracl(Islen1)naca{l'cin!tnID.Donisafolkmedicineusedforrheumatism.Weinvestigat--editandisolatedanewminorcyclopeptidebrachysteminAl,togetherwiththreeknownheterocyclesL-pyroglutamicacid2,2-minaline3and3'-furfuryl-pyrrole-2-carboxylate41.ThestructureelucidationoflwasmadebylDand2DNMRtechniques.BrachysteminAl,wasnegativetoninhydrinreagentbutpositiveafterhydroIysiswith6mol/LHCl2.Themolecularforn1uIaC,,H,'O,N,wasderivedfromtheHR-FABMS([M H] atIn/z755.4o73,Calc.forI)l/:755.4o92).lRbandsat…     

质粒DNA在灌注色谱基质上的吸附行为

Anion exchange chromatography is the most popular chromatographic method for plasmid separation.POROS R1 50 is a perfusio n chro mato graphic suppo rt w hich is a reversed phase matrix and is an alternative to co nventio nal o nes due to its mass transfer pro perties.The adso rptio n and elutio n o f the pIDKE2 plasmid o nto reversed phase POROS R1 50 w as studied.Langmuir iso therm mo del w as adjusted in o rder to get the max imum adso rptio n capacity and the disso ciatio n co nstant fo r POROS R1 50-plasmid DNA(pDNA) system.Breakthro ugh curves w ere o btained fo r vo lumetric flo w s betw een 0.69-3.33 mL/min,given dynamic capacity up to 2.3 times higher than tho se repo rted fo r io nic ex change matrix used during the purificatio n pro cess o f plasmids w ith similar size to that o f pIDKE2.The efficiency w as less than 45% fo r the flo w co nditio ns and initial co ncentratio n studied,w hich means that the suppo rt w ill no t be o perated under saturatio n circumstances.     

SEPARATION OF OVERLAPPING INCISIONS OF A.C.OSCILLOPOLAROGRAM USING KALMAN''''S FILTER TECHNIQUE

Kalman's Filter Technique for the separation of overlapping incisionsof an a.c.oscillopolarogram is presented,the experimental verifications werecarried out in various systems with the ions of Pb~(2+),Tl~+,In~(3+)and Cd~(2+).The resultsshowed that the concentration of the depolarizer can be determined directly andeasily with this technique in the presence of interference elements.     

Formation of Benzyl Oxazole, A Competitive Path with the Classical Bishler-Napieralski Reaction

1,2,3,4-tetrahydroisoquinoline-3-carboxylic acids (TIC) are of considerable interest due to their biological activity and as an important structural element in several important alkaloids and other medically useful products1. Moreover, TIC is a phenylalanine analogue in which the dihedral angle is limited to a very small range because of its bicyclic nature2. In connection with the design of topographically constrained peptides, TIC has been utilized in several instance as a replacement o…     

A New Chromone Derivative from Stellera chamaejasme L.

A new chromone derivative,3-[1-(2,4,6-trihydroxyphenyl)3-di-(4-hydroxyphenyl) 1-propanone-2-yl]5,7-dihydroxy-8-di(4-hydroxyphenyl)methyl-4H-1-benzopyran-4-one,named as isomohsenone was isolated from the roots of Stellera chamaejasme L.together with known chamaechromone. Its structure was determined by the analysis of MS and NMR data,especially 2D NMR spectra.     

Two New Monoterpene Diglycosides from Winchia calophylla A. DC

Two new monoterpene diglycosides, wincaloside A (1) and wincaloside B (2), along with loganin (3) were isolated from the stem barks of Winchia calophylla A. DC. The structures of 1 and 2 were established by spectroscopic and chemical methods.