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1.
The structures of the products of the polyformylation of Cu, Ni, and Co complexes of etioporphyrin (EP) as monoformyl-, ,-diformyl-, ,-diformyl-, and ,,-triformyl-EP were established by electronic, IR, and PMR spectroscopy and mass spectrometry. -Formyl--(N-methylformaldimine)-EP and porphyrins that contain a cyclopentane ring can be formed by alkaline treatment of the Vilsmeier formylation products.See [1] for communication 8.See [2] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 767–775, June, 1979.  相似文献   

2.
The isolation of four triterpene glycosides from the roots of the dahurian anemonePulsatilla dahurica (Fisch. ex DC) Spreng, is described together with their identification, on the basis of chemical transformations, spectral characteristics, and literature analogies, as hederagenin 3-O--L-arabinoside, hederagenin 3-O-[O--D-glucopyranosyl-(12)--L-arabinopyranoside], hederagenin 3-O--L-arabinopyranoside 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside], and hederagenin 3-O-[O--D-glucopyranosyl-(14)--L-arabinopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside].Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, Nos. 3,4, pp. 349–356, May–August, 1992.  相似文献   

3.
Conclusions An efficient method for the synthesis of ,,-trihydropolyfluoroalkyl chlorophosphates is by reacting ,,-trihydropolyfluoroalkyl dichlorophosphites and bis-(,,-trihydropolyfluoroalkyl) phosphites with sulfuryl chloride. It has been found that in three-coordinated polyfluoroalkyl phosphites, the high electronegativity of the polyfluoroalkyl groups hinders cleavage of the latter on reaction with sulfuryl chloride, thereby facilitating the formation of oxidation products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 146–149, January, 1988.  相似文献   

4.
Summary 1. The synthesis of the following neutral plasmalogens has been effected: -O-(octadec-1-enyl)-, distearoylglycerol, -O-(octadec-1-enyl)-, -dipalmitoylglycerol, -O-(hexadec-1-enyl)-, -distearoylglycerol, and -O-(pentadec-1-enyl)-, -dipalmitoylglycerol.2. During the synthesis, the following compounds were isolated and characterized by their physicochemical constants: the -octadec-1-enyl ether of glycerol, -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, the tosylate of -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, and -O-(2-tosyloxyoctadecyl) glycerol.3. The IR spectra of the -octadec-1-enyl ether of glycerol and the neutral plasmalogens have been studied.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 367–371, 1966  相似文献   

5.
Heats of dilution of aqueous solutions of the following di-and tripeptides were determined at 25°C over a wide concentration range: -alanyl-glycine, -alanyl--alanine, DL--alanyl-glycine, glycyl-DL--alanine, L--alanyl-L-alanine, DL--alanyl-DL--alanine, DL--alanyl-DL-valine, DL--alanyl--alanine, glycyl--aminobutyric acid, glycyl-L-leucine and DL--alanyl-glycylglycine. The excess enthalpies Hex and partial molar relative enthalpies L2 were calculated and enthalpy coefficients of intermolecular interaction were analysed using the additivity principle of Savage and Wood. The concentration dependence of the enthalpic characteristics of peptide-peptide interactions is discussed based on of their hydrophobicity and hydrophilicity. The three-stage model of peptide association is described using enthalpic coefficients of intermolecular interactions.  相似文献   

6.
The epoxide ring opening of 16,17-epoxy-17-ethynylandrost-4-en-3-one and its dicobalt hexacarbonyl complex on reacting with Py·HF, Py·HCl, and Py·HSCN was studied. The results of these reactions and the structure of the end products depend not only on the complexation of the acetylene bond, but also on the nucleophilic reagent used. On the basis of the reaction of a Co-coordinated 16,17-epoxy-17-ethynylandrost-4-en-3-one there has been developed a preparative method for the synthesis of pregn-4-ene-3,20-dione-[17,16-d]-1,3-oxazolidin-2-one.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp. 2661–2666, November, 1992.  相似文献   

7.
-Cyclodextrin having cinnamamide at 6- or 3-positions (6-CiNH--CD, 3-CiNH--CD) and -cyclodextrin with cinnamamide on 6-position (6-CiNH--CD) have been prepared. Supramolecular structures were formed in the solid state or aqueous solutions and characterized by measurements of NMR and vapor pressure osmometry (VPO). The results indicate that 6-CiNH--CD formed insoluble supramolecular polymers in the solid state, while 6-CiNH--CD and 3-CiNH--CD formed supramolecular complexes in aqueous solutions. 6-CiNH--CD was found to form a dimer in an aqueous solution. 3-CiNH--CD formed intermolecular complexes to give supramolecular polymers. The differences of the position of guest part on cyclodextrins caused to give a variety of supramolecular structures in aqueous solutions.  相似文献   

8.
Apparent standard Gibbs energy, enthalpy, entropy, and heatcapacity data of the interactions of -cyclodextrin (CD) to some n-carboxylatesH(CH2)nCOO- (n = 4–6), are determined by isothermal titration microcalorimetryat different temperatures in phosphate buffer, pH 9.0, assuming a 1 : 1 model indilute solution. Modelling of contributions of the thermodynamic properties of the solutionindicates that CD undergoes conformational change upon binding to homologousseries of n-carboxylates, n-alcohols, ,-alkane dicarboxylates and ,-alkane diols.  相似文献   

9.
Four new polyhydroxysteroids, 5-cholesta-3,5,6,15,16,25,26-heptaol, 24-ethyl-5-cholesta-3,5,6,15,28,29-heptaol-29-sulfate, (22E)-24-methyl-5-cholest-22-ene-3,5,6,15,25,26-hexaol-26-sulfate, 24-propyl-5-cholesta-3,5,6,8,15,28,29-heptaol, and the known 5-cholesta-3,5,6,15,16,26-hexaol, have been isolated from the starfishCtenodiscus crispatus.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1821–1825, October, 1994.  相似文献   

10.
Zusammenfassung Die Synthese von 3, 16-Diacetoxy-5 -pregnan-20-on (VI) aus 3-Acetoxy-5 -pregn-16-en-20-on und eine verbesserte Darstellung von 3, 16-Diacetoxy-5 -pregnan-20-on (III) aus 3-Acetoxy-pregna-5, 16-dien-20-on werden beschrieben.  相似文献   

11.
Summary 1. The synthesis of L-(+)--oleoyl--linoleoyl--glycerylphosphorylethanolamine has been effected.2. During the investigations the following substances were isolated and characterized: L--oleoyl--glycerylphosphoryl-N-phthaloylethanolamine and L---linoleoyl--glycerylphosphoryl-N-phthanoylethanolamine.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 2, pp. 80–83, 1966  相似文献   

12.
Zusammenfassung Es wurde ein allgemein anwendbarer Weg zur Herstellung von in -Stellung basisch substituierten 4,10-Trimethylenphenthiazinen durch Umsetzung der aus den -Hydroxyverbindungen erhaltenen -Bromverbindungen mit sekundären Aminen angegeben. Für das in der Literatur bekannte -Amino-4,10-Trimethylen-phenthiazin wurden neue Darstellungen beschrieben.  相似文献   

13.
In aqueous and aqueous-ethanolic buffer solutions at pH<9, 2, 2-bifuryl and 2, 2-furoin give two-electron polarographic electroreduction waves, the half-wave potentials of which depend on the pH. The primary product of the electroreduction of 2, 2-bifuryl is trans-1,2-dihydroxy-1,2-bis(, -furyl)ethylene, which then rearranges into 2, 2-furoin. The anode-cathode wave of 2,2-bifuryl has been studied by means of a Kalousek commutator. It has been shown that the polarographic behavior of 2,2-bifuryl and 2, 2-furoin is similar to that of benzil and benzoin, but differs from the behavior of analogs of the pyridine series.  相似文献   

14.
The composition of the mono- and sesquiterpenoids from the oleoresin of the Khingan fir has been studied. Thirteen monoterpenoids have been identified — bornyl acetate, -terpenyl acetate, geranyl acetate, citronellyl acetate, -fenchyl acetate, linalool, geraniol, terpineol-4, -terpineol, -fenchol, borneol, sabinene hydrate and thymol methyl ether; and 19 sesquiterpenoids — -longipinene, longicyclene, longifolene, -copaene, -ylangene, sibirene, -and -selinenes, - and -cadinenes, -muurolene, caryophyllene, -humulene, - and -bisabolenes, ar-curcumene, nerolidol, bisabolol, and -cedrol. The crystal structure of -cedrol has been investigated by x-ray structural analysis.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 41–45, January–February, 1985.  相似文献   

15.
A new withasteroid — vamonolide — has been isolated from the epigeal part ofPhysalis angulata L. (Solanaceae). On the basis of spectral characteristics, its structure has been established as 5,14-dihydroxyl-l-oxo-6,7-epoxy-20R,22R-with-2-enolide.Institute of the Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 856–858, November–December, 1987.  相似文献   

16.
PM3 calculations were performed on the complexation of -cyclodextrin (-CD) with nitrobenzene, benzoic acid, benzoate anion, 4-nitrophenol, and 4-nitrophenolate anion. The results, in agreement with the experimental observations, indicated that the complex -CD-benzoic acid was more stable than -CD-nitrobenzene, and -CD-4-nitrophenolate was more stable than -CD-4-nitrophenol. Frontier orbital analysis suggested that charge-transfer interaction led to such behaviors, and hence constituted a nontrivial driving force in the molecular recognition of -CD.  相似文献   

17.
Summary The visible absorption spectra of the cross-sections of the dyed various synthetic-polymer fibres were measured by means of a microspectrophotometer. We found that the spectra of Acridine Orange hydrochloride in the crosssections of fibres showed a maximum of -band and band, and the spectra of Acridine Orange (free base), indicated a maximum of -band, -band and the crystal peak of the dye. These results suggest that the monomeric state, the aggregate as well as the crystal of the dye exist in these dyed synthetic-polymer fibres.
Zusammenfassung Die sichtbaren Absorptionsspektren der Querschnitte der verschiedenen gefärbten synthetischen Polymerfasern wurden mit einem Mikrospektrophotometer gemessen. Dabei wurde herausgefunden, daß die Spektra der Acridinorange Hydrochloride in den Querschnitten ein Maximum beim -Band und beim -Band und die Spektra der Acridinorange (freie Base) ein Maximum beim -Band, -Band und beim Kristallpik der Farbstoffe zeigen. Diese Resultate deuten darauf hin, daß sowohl der monomere Status, als auch Aggregate und die Kristalle der Farbstoffe in diesen synthetischen Polymerfasern existieren.
  相似文献   

18.
Zusammenfassung Aus den entsprechenden -Bromestern werden durch Umsetzung mit Natriumnitrit die -Oximinodicarbonsäuredimethylester C7 und C9 und der , -Dioximinoazelainsäuredimethylester erhalten. -Methyladipinsäure wird zum Gemisch aus -Bromund -Bromester umgesetzt. Mit Natriumnitrit wird -Nitro-und -Oximino--methyladipinsäuredimethylester erhalten.
The -oximino dicarboxylic dimethyl esters of C7 and C9 and the , -dioximino azelaic acid dimethyl ester are received from the corresponding -bromo esters by reaction with sodium nitrite. -Methyladipic acid is reacted with bromine to a mixture of the -bromo and -bromo ester. Reaction with sodium nitrite gives the -nitro ester and the -oximino ester of -methyl adipic acid.


5. Mitt.:H. Reinheckel, Mh. Chem.98, 1217 (1967).  相似文献   

19.
In the course of a systematic optimization of the materials properties of -HgI2 crystals for room temperature - and X-ray detectors, we have investigated possible sources of defects and discuss briefly the possibility to supress them. Due to the particular structure of -HgI2, large amount of impurities, particularly hydrocarbons, can be absorbed invan der Waals layers and lattice channels. Purification by sublimation does not work due to the affinity of hydrocarbons to iodine and their easy re-absorption in the sublimate. Lattice filtering of the large concentration of hydrocarbons contained even in suprapure iodine has been performed using the close spaced lattice of CuI. Oxidation of hydrocarbons by reaction of oxygen with HgI2 is another possibility for their removal.Mass spectrometric investigations of a molecular beam of -HgI2 has solved the long disputed problem of the existence of nonstoichiometry: both excess of Hg or excess of I are possible. The removal of nonstoichiometry can be achieved by suitable thermal treatment only in the case of pure crystals. In the presence of hydrocarbons, the non-stoichiometric defects are fixed showing the predominant importance of hydrocarbons for -HgI2.Investigation of the evaporation of -HgI2 with mass spectrometry at low temperatures (150>T>40 °C) shows a strong change of the enthalpy of evalporation at 67 °C whereas DSC does not show any peak at this temperature. It seems probable that this is due to a surface reconstruction which influences the evaporation but not the thermal bulk lattice effects which are detected by DSC.Dedicated to Prof. Dr.K. L. Komarek at the occasion his 60th birthday.  相似文献   

20.
Zusammenfassung Aus biologischem Material durch Dünnschichtchromatographie abgetrennte und aus den Chromatogrammflecken eluierte Ascorbinsäure wurde mit Eisen(III)-chlorid und,-Dipyridyl kolorimetrisch bestimmt. Als Schichtmaterial wurde Kieselgel verwendet, dessen Eisengehalt vorher mit ÄDTA gebunden wurde. Als Fließmittel diente eine Mischung aus Eisessig, Aceton, Methanol, Benzol und n-Butanol.
Summary Ascorbic acid that has been separated from biological material by thin layer chromatography and eluted from the chromatogram stains was determined colorimetrically with iron(III) chloride and ,-dipyridyl. Silica gel was used as the layer material; its iron content was bound previously with EDTA. A mixture of glacial acetic acid, acetone, methanol, benzene andn-butanol served as the mobile phase.
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