Studies on the Steroids of Marine Sponge(Ⅳ)──Steroids from the Marine Spo

ＳｔｕｄｉｅｓｏｎｔｈｅＳｔｅｒｏｉｄｓｏｆＭａｒｉｎｅＳｐｏｎｇｅ（Ⅳ）──ＳｔｅｒｏｉｄｓｆｒｏｍｔｈｅＭａｒｉｎｅＳｐｏｎｇｅＢｉｅｍｎａＳｐ．ＺＥＮＧＺｈｉ，ＳＵＪｉｎｇ－ｙｕａｎｄＺＥＮＧＬｏｎｇ－ｍｅｉ（ＤｅｐａｒｔｎｉｅｎｔｏｆＣｈｅｍ...     

Two Phaeophytin Type Analogues from Marine Sponge Dysidea sp.

A new compound named 13b (S)-hydroxy-17c-ethoxypheaophorbide a (2) together with a known compound 17c-ethoxypheaophorbide a (1) were isolated from marine sponge Dysidea spcollected in South China sea. The structures were elucidated by spectroscopic analysis as well as comparison with those reported in literatures.     

Studies on Tricyclohexyltin ( Ⅳ ) Diaryldithiophosphates

Fourteen new tricyclohexyltin (Ⅳ)-O,O-diaryldithiophosphates were synthesized and determined by IR, 1H NMR, 13C NMR, 119Sn NMR MS, and elemental analysis. The structures of all the compounds consist of discrete molecule containing a four-coordinated tin atom. Results from the preliminary biological test show that these compounds have a high miticidal activity.     

Chemical Studies on the Glycosides in the Leaves of Oplopanax Elatus Nakai(Ⅳ)

ＣｈｅｍｉｃａｌＳｔｕｄｉｅｓｏｎｔｈｅＧｌｙｃｏｓｉｄｅｓｉｎｔｈｅＬｅａｖｅｓｏｆＯｐｌｏｐａｎａｘＥｌａｔｕｓＮａｋａｉ（Ⅳ）＊ＷＡＮＧＧｕａｎｇ－ｓｈｕａｎｄＸＵＪｉｎｇ－ｄａ（ＮｏｒｍａｎＢｅｔｈｕｎｅＵｎｉｖｅｒｓｉｔｙｏｆＭｅｄｉｃａｌ...     

Chemistry of α-mangostin. Studies on the semisynthesis of minor xanthones from Garcinia mangostana

α-Mangostin is the major prenylated xanthone from Garcinia mangostana and it has been used also in recent times as starting material for the semisynthetic preparation of various biologically active derivatives. Its structure is characterised by the presence of few functional groups amenable to chemical manipulations, but present in the molecule in multiple instances (three phenolic hydroxyl groups, two prenyl chains and two unsubstituted aromatic carbons). This study represents a first approach to the systematic investigation of the reactivity of α-mangostin and describes the semisynthesis of some minor xanthones isolated from G. mangostana.     

Studies on Agarofurans Ⅳ. The Synthesis of 4-Substitutioned Agarofurans

Agarowoodoilwasfoundtobebioactiveinpharmacologicalscreeningforthenervoussysteminourinstitute.AgarofuransareonesmicturaltypeoftheimportantconstituentSofagarowoodoil.Q-Agarofuran(lh),oneofthemanyconstitUentsoftheoil,issuspectedofbeinganimportantcontributortothebioactivity.AlthoughseveralsynthesisofQ-agarofuran(fo)havebeendescribed'-',theyarenotsuitableforthesynthesisofitsanalogs.Thebioactivitiespromptedustodevelopanewroutetoa-agarofuran(fo)anditsanalogs.EarliersynthesisofQ-agarofuran(lb),with…     

Studies on the Structure of Kansuinine A from Euphorbia kansui

Kansuinine A is a macrocyclic jatrophane diterpene that was isolated from Euphorbia kansui.Further investigation of the structure was revealed that the benzoyl group located at C-8 and the position of C-3 was the present of an acetyl group by means of HMQC,HMBC spectra.     

Studies on the synthesis and magnetic property of binuclear oxovanadium(Ⅳ) complexes ridged by chloranilato group

Six novel oxovanadium(IV) binuclear complexes have been synthesized and characterized,namely,[(VO)2(CA)La]SO4 [L denotes 5-methyl-l,10-phenanthroline (Me-phen);2,9-dimethyl-1,10-phenanthroline (Me2-phen); 5-chloro-l,10-phenanthroline (Cl-phen); diaminoethane (en); 1,3-diaminopropane (pn) and 1,2-diaminopropane (ap) respectively.],where CA represents the dianion of chloranilic acid.Based on elemental analyses,molar conductivity and room temperature magnetic moment measurements,IR and electronic spectral studies,it is proposed that these complexes have CA-bridged structures and consist of two vanadium(IV) ions in a square-pyramidal environment.The complexes [(VO)2(CA)(Me-phen)2]SO4 (1) and [(VO)2(CA)(Me2-phen)2]SO4 (2) were characterized by variable temperature magnetic susceptibility measurements (4~300 K) and the observed data were fitted to the modified Bleaney-Bowers equation by the least-squares method,giving the exchange integral J=-15.8 cm-1 for 1 and J=-10.6 cm-1 for 2.This result indicates that t     

Studies on the Synthesis of Preverecynarmin

Prev~n1,acembranopditerpenoid,wasfirstisolatedfromsoftcoral(VeretilIumcoporium)inl99(),anditSmCtUrwasehablishedas(+)-(lE,3E,7E,llE)-cembra-l,3,7,ll-tetraen6-olaeetate[l].SofarasweknOW,thetotalSynthsisof1hasnobeenrePOrtedyet.Herein.wewishtodescribethetotalpeisoftheprecursor(9),theSynthhcroutewasouthnedbelowfa)HBr.80%;b).CH3C02Na.CH3CO2H,75%,c).Se02-I-Bu00H,70%,d).CCl',PPh3,83%,e).NaSQPh.DMF.9O%,O.K=CO3.MeOH,95%,g).DHP,Ts0H.8O%,h),TBAB,5O%NaOH,aq.,5%;i).Li-Effez.M,70%;j…     

Studies on the Synthesis of Villosol

TheindoidsxillosoIandt4llosolsidewereisolatalinl985frOmPatriDiavi11osa,atradihonalChineseherbmedicineusedfortreatofconunoncoldandparohhsmUInPS.PhannacologicalstUdieshaveestablishedthattheyshowanti-inflannnatOryachvihes.BasedonspeCtraldata,chenucaltransformationsandanalysisOfCDbehaviorofthelactonering,x-illosolsideandvillosolhavebeengivensmictUresland2respeCtively.[']Itisinterestingthatthesenot-eltridoidshat,ereversedstereocheAnsto'atC5andC9junCtUreSwith5Q,9Qinsteadoftheusuall}'found5…     

Studies on the Interaction of Poly

Studies　on　the　Interaction　of　Poly...     

Studies on the biosynthesis of arteannuin

In previous communications we have reported that arteannuic acid(1,Scheme1)is a common precursor of the biosynthesis of both arteannuin(2)and arteannuinB(3)by the leaf homogenate of the plant Qinghao(Artemesia annua L.).It seemsthat most likely the oxidation of allylic tertiary carbon atom,C-6,may occur early inthe biosynthetic path of 2 and 3 from 1.Natural 6-epi-deoxyarteannuin B(4)isolated     

Studies on Agarofurans VIII. Synthesis of the Metabolites of 4-Butyl-a-agarofuran

Agarofurans have been found to be active on the nervous system in our institute. 4-Butyl-a-agarofuran 1 is a promising drug candidate. In order to explore the pharmacokinetics of 1, the metabolism of 1 in vitro was studied with liver microsomes from rats. Five metabolites were isolated and structures were identified as compounds 2-6. But the absolute configuration of 2,4,5 and the position of carbonyl in 3 could not be unambiguously determined. Further determination was limited by the smal…     

Studies on the Chemical Constituents of Oxytropis Glabra DC (I)

Two new triterpenoid sapon.ins 1 and 2 were isolated from the crude saponin extract of Oxytropis glabra DC by Si gel chromato-grapny . Saponins 1 and 2 were determined to be 3-0-1 β-D-glucopyranosy 1 (1-2)- β -D-glucuronopyranosyl azukisapogenol methyl ester and 3-O-[β-D-glucopyranosyl(1 - 2 ) - β -D-glucuronopyranosyl] azukisapogenol amide, respectively by spectral analysis and chemical methods.     

Studies on Chemical Composition of Anemone Altaica C.A.May (Ⅱ)

A new dispirolactone compound,C10H12O6 m.p.224-226℃,wasisolated from the ethyl acetate extract of the roots of anemone aJ-taica C.A.May,the Chinese medicinal herb,by using Si gel column chromatography.Its structure was determined as: 1,6,9,13-tetra-oxadispiro[4,2,4,2]tetradecane-2,10-dione by means of IR,NMR,MS spectra and X-ray diffraction analysis.     

Studies on the diterpenoid constituents from Rabdosia angustifolia

Two new ent-kaurene diterpenoids, angustifolin B and natural hydrogen-bonded 1:1 complex, angustifolin C, as well as four known diterpenoids, angustifolin, isodonal, sodoponin, tri-chorabdal B, were isolated from the leaves of Rabdosia angustifolia.     

Studies on the Antiviral Activities in vitro of Polysaccharide from Eucheuma striatum

To assay the antiviral activities on HSV-1 and CVB3 in vitro of the polysaccharide from Eucheuma striatum, its antiviral mechanism was explored. Vero cells were infected by HSV-1 and CVB3, and they were cultured with serial dilutions of polysaccharide. The cells cytotoxicity of Polysaccharide was evaluated by the MTT method. The inhibitory effects were evaluated by the cytopathic effect (CPE). Its antiviral mechanism was researched by the method of giving samples in different time. The polysaccharide could inhibit the CPE of cells infected by HSV-1 and CVB3. It showed low cytotoxicity on vero cells. Its antiviral activities were better than those of acyclovir and ribavirin which were run in parallel as the positive control samples. The polysaccharide from Eucheuma striatum has potent antiviral activities. Its antiviral mechanism is that it can prevent the virus from absorbing to the cell surface.     

Studies on the biosynthesis of arteannuin——Ⅳ.The biosynthesis of arteanniuin and arteannuin B by the leaf homogenate of Artemisia annua L.

Arteannuic acid and(-)11R,13-d ydroarteannuic acid are the key intermediates in thebiosynthesis of arteannuin by the leaf homogenate of Artemisia annua L.,and arteannuic acid andepoxyarteannuic acid are the intermediates of arteannuin B.and epoxyarteannuic acid can not betransformed into arteannuin by the homogenate.     

Studies on Steroids. CLXXXIL. Determination of 6β-Hydroxycortisol in Urine by High-Performance Liquid Chromatography with Fluorescence Detection

Abstract

A new sensitive method for the determination of 6β-hydroxycortisol in urine by high-performance liquid chromatography with fluorescence detection has been developed. 6β-Hydroxycortisol and its C-6 epimer (internal standard) were transformed quantitatively into the 21-(9-anthroyl) derivatives when treated with 9-anthroyl nitrile in the presence of triethylamine in acetonitrile. The resulting fluorescent esters were readily separated on a Cosmosil SSL column using ethyl acetate/hexane (2:1) as a mobile phase with a detection limit of 25 pg. The efficient clean-up was achieved by the combined use of Bond Elut and Clin Elut cartridges. The present method is applicable to the quantification of 6β-hydroxycortiol in human urine with satisfactory accuracy and precision.     

Studies on the Stability of Four－membered Ring Chelates（Ⅳ）──Sulphur Coordinated Xanthate Complexes

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