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1.
The structure of vincarodine has been determined to be 1 by an investigation of its IR.-, UV.-, 1H- and 13C-NMR.- and mass spectra. A 13C-NMR. analysis has been performed on the bases vincamine ( 2 ), epivincine ( 9 ), 14, 15-dehydrovincine ( 7 ) and its 16-epimer ( 8 ).  相似文献   

2.
Structure Determination of N6-, 9-and 7-Acyladenines by 1H- and 13C-NMR Spectroscopy of Solids and in Solution . Adenine (1) reacts with carboxylic acid anhydrides or chlorides 2 to yield the acyladenine isomers 3–5 . The isomeric structures were determined by 33C- and 1H-NMR spectroscopy in solution and by solid-state 13C-NMR spectroscopy.  相似文献   

3.
1H- and 13C-NMR.-spectra of 6-(p-X-phenyl)fulvenes The 1H- and 13C-NMR.-spectra of a series of 6-(p-X-phenyl)fulvenes 3 , measured at 9.39 T (93.9 kgauss), have been analyzed. In these compounds, electronic effects due to the substituent X clearly exert changes in chemical shifts as well as in coupling constants in the 5-membered ring. Small changes in bond length are observed by comparison of the vicinal 1H, 1H-coupling constants, whereas changes in charge densities linearly influence the chemical shifts of C(5), C(2) and C(3).  相似文献   

4.
ω-Alkenoic acids, either commercially available or synthesized, were esterified to their corresponding methyl esters. They were characterized by their infrared, 1H-, and 13C-NMR spectra. The ω-alkenoates prepared were: propenoate (acrylic acid), butenoate, pentenoate, hexenoate, heptenoate, octenoate, nonenoate, and decenoate. These compounds were epoxidized with m-chloroperoxybenzoic acid to the corresponding methyl ω-epoxyalkanoates. The rate of epoxidation of the double bond is found to increase as the double bond is separated from the carbomethoxy group by increasing numbers of methylene groups. When at least three methylene groups are inserted, the rate of epoxidation becomes constant and is similar to the epoxidation of ω-olefins. The methyl ω-epoxyalkanoates were characterized by their infrared, 1H-, and 13C-NMR spectra. Methyl ω-alkenoates and methyl ω-epoxyalkanoates were prepared and characterized, and their purification was studied in preparation for their investigation as monomers for olefin or epoxide polymerization using corrdination initiators.  相似文献   

5.
1H-and13C-NMR. spectra of methyl esters of the diastereomeric (±)-dihydropalustramic acids; structural correlation of (?)-dihydropalustramic acid with the alkaloid palustrin Unambiguous assignment of cis-trans configuration at the piperidine ring of the four diastereomeric methyl esters of the (±)-dihydropalustramic acids is based on the interpretation of 1H- and 13C-NMR. data. (?)-Dihydropalustramic acid, the important degradation product of the alkaloid palustrin is shown to be threo-cis-[6-(1-hydroxypropyl)-2-piperidyl]acetic acid. The same conclusion holds for palustrin and dihydropalustrin. Therefore, palustrin is threo-cis-17-(1-hydroxy-propyl)-1,5,10-triazabicyclo[11.4.0]heptadec-15-en-11-one.  相似文献   

6.
Spectroscopic Studies on Sulphur Compounds. VII. 1H- and 13C-NMR Spectroscopic Investigations of Sulphinic Acid Chlorides and Chloro-sulphurous Acid Alkylesters The temperature dependent 1H- and 13C-n.m.r. spectra of the sulphinic acid chlorides R—S(O)Cl and of the chloro-sulphurous acid alkylesters RO—S(O)Cl with R = CH3CH2- and (CH3)2CH- have been measured. The differing behaviour of both nuclei is discussed in terms of inversion at the chiral sulphur atom.  相似文献   

7.
Poly [bis(phenoxy)] phosphazene sulfonic acid and its mixed substitution derivatives containing N-methylsulfonamide, sulfonylaminoacetic, and free sulfonic acid functions have been obtained and characterized by IR and 1H-, 31P-, 13C-NMR spectroscopy. The polymers are all water soluble. Poly [bis(4-benzoylphenoxy)] phosphazene sulfonic acid could not be obtained due to chain degradation during the synthesis.  相似文献   

8.
The 13C-NMR. in Zn(II)(Porphin), Fe(III)(Porphin)(CN2), Zn(II)(Tetraphenyl-porphin), and Fe(III)(Tetraphenylporphin)(CN2) have been identified, and the 13C hyperfine shifts in the iron complexes evaluated. It was found that dipole-dipole coupling with the electron spin localized in the π-orbitals of the aromatic carbon atoms makes an important contribution, to the 13C hyperfine shifts. In a preliminary analysis the experimental spin density distribution obtained from the combined 1H- and 13C-NMR.-data is compared with theoretical models of the iron porphyrin complexes.  相似文献   

9.
Oxidation of the title compound with m-chloroperbenzoic acid affords a keto-lactone, two bis-lactones and a bis-spirolactone, in varying amounts depending upon the reaction conditions. The structures were established by means of X-ray diffraction, 1H- and 13C-NMR spectroscopy.  相似文献   

10.
The potent immunosuppressant drug FK506 ( 2 ) has been examined by 1H- and 13C-NMR spectroscopy and NOE-restrained molecular dynamics to elucidate the conformation in solution. A combination of two- and three-dimensional NMR techniques was used to completely assign the 1H- and 13C-NMR chemical shifts of the two configurational isomers resulting from the cis-trans isomerization about the single amide bond. Hetero- and homonuclear coupling constants were measured to assign the diastereotopic methylene protons at C(16), C(18), and C(23). Intramolecular H? H distances were defined from NOESY spectra recorded at ?30° in CDCl3 and used as constraints in molecular-dynamics simulations. The conformational preferences of 2 in solution are discussed in light of the constitutional features recently proposed to be necessary for binding and activity.  相似文献   

11.
Preparation of 1, 1-difluorobenzocyclopropene (4) and of its 2, 5- and 3, 4-dideuterio derivatives 4a and 4b is reported. Upon ionization in cold fluorosulfonic acid, 4 affords 1-fluorobenzocyclopropenium ion (6) . 1H- and 13C-NMR. spectra of 4 and 6 are assigned on the basis of the data for the specifically deuteriumlabelled compounds 4a and 6a . Hydrolysis of 6a leads to 2, 5-dideuteriobenzoic acid (7a) .  相似文献   

12.
The configuration of camphenilanic acid (1) has been determined by NMR-spectroscopic studies.1H-,13C-NMR and 2D-shift correlation spectroscopy have been used. The socalled camphenanic acid is identical with1, isocamphenanic acid appears to be a mixture of1 and2, the same is true for different camphenilanic acids described in the literature.  相似文献   

13.
Unsaturated cyclic and bicyclic hydrocarbons react with chloral in presence of aluminium chloride to yield tricyclic oxabrexanes which undergo acid catalyzed rearrangements to oxabrendanes. 1,5-cyclooctadiene gives the new oxa-cyclo[c, d]octahydropentalen. Structural evaluations and stereochemical assignments are discussed on the basis of detailed 1H- and 13C-NMR.-spectra.  相似文献   

14.
《European Polymer Journal》1986,22(9):735-743
The amidation of syndiotactic polyacids and the 1H- and 13C-NMR spectroscopic characterization of the resulting polyamides are described. The polyacids have been derived from syndiotactic poly(2-methylallyl alcohol) by esterification with cyclic dicarboxylic acid anhydrides, including Nα-protected aspartic acid anhydrides and glutamic acid anhydrides. The poly(hydrogen carboxylate) were in turn condensed with a series of amines, some of which possessed additional functional groups, e.g. (L)-1-phenylethylamine, histamine, and glycine methylester.  相似文献   

15.
High conversion methyl methacrylate (MMA)-methacrylic acid (MA) copolymers prepared by two different emulsion polymerization processes were characterized in terms of composition and sequence distribution by 1H- and 13C-NMR, taking into account the conversion effect. A rapid and selective counting procedure for calculating the compositional configurational pentads (512 values) in these copolymers is described. From this counting procedure and using the Klesper's assignment of the 18 peaks observed in the 13C-NMR carbonyl resonance spectrum of the copolymers, a relatively good agreement was found between the calculated and experimental fractions of each peak intensity. Moreover, this study allows differences in compositional homogeneity to be characterized as a function of the nature of the emulsion polymerization process.  相似文献   

16.
Arylation Reaction of Cyclic Guanidine-Analogs with α-Halo- anthraquinones: New Anthrapyrimidines 2-Amino-benzimidazole gives on Ullmann-reaction with α-halo-athraquinones such as 1-amino-4-bromoanthraquinone-2-sulfonic acid (la) the new benzimidazo-anthrapyrimidine 2a , whereas 3-amino- triazole gives under the same conditions two products: the 1,2,4-triazoloanthrapyrimidine 7 and l-amino-4-(3-amino-1,2,4- triazolyl)anthraquinone-2-sulfonic acid ( 8 ). The new structures were elucidated by 1H- and 13C-NMR. and X-ray analysis.  相似文献   

17.
1H-, 2H- and 13C-NMR spectra have been used to test the Ni2+ solvation shell composition in the 1.1 molal methanol solution of NiCl2. It has been confirmed that Cl? anion takes part in the nearest environment of Ni2+ cation at all the temperatures investigated. Using 2H-NMR allowed us to detect for the first time OD-signal of methanol in the primary solvation shell of Ni2+ cation. Both 2H- and 13C-NMR spectra show that the composition of the cation solvation shell becomes more complicated at temperatures lower than 220?K.  相似文献   

18.
Schiff-base complexes of cobalt(II), nickel(II), copper(II) and, zinc(II) with 3-ethoxysalicyliden-p-aminoacetophenoneoxime (HL) were prepared and characterized on the basis of elemental analyses, IR, 1H- and 13C-NMR, electronic spectra, magnetic susceptibility measurements, molar conductivity and thermogravimetric analyses (TGA). A tetrahedral geometry has been assigned to the complexes.  相似文献   

19.
1H-NMR., 13C-NMR., UV. and CD. spectral data of synthetic (3S, 3′S)-astaxanthin, its 15-cis isomer, and some related compounds 1H-NMR., 13C-NMR., UV. and CD. spectra are reported for synthetic (3S, 3′S)-astaxanthin ( 1 ), its 15-cis isomer ( 2 ), its diacetate ( 3 ), and the 15, 15′-didehydro compound ( 5 ). These data prove the identity of the synthetic and the naturally occuring compound 1 . A full interpretation of the 1H- and 13C-NMR. spectra is given and confirms the configuration of all the double bonds. The conformation of the cyclohexene end group of all the compounds is shown to be identical. The signs of the different CD. maxima of 15-cis-astaxanthin are found to be opposite to those of the all-trans compound.  相似文献   

20.
Summary The synthesis of some novel guanylhydrazones derived from aromatic aldehydes (benzylideneaminoguanidines) is described. Structural assignments of these compounds as well as of some already known congeners, particularly with respect to the configuration of the HC=N double bond, were achieved using1H- and13C-NMR data as well as homonuclear NOE difference spectroscopy.
Zur Struktur von Guanylhydrazonen aromatischer Aldehyde
Zusammenfassung Die Synthese einiger neuer Guanylhydrazone abgeleitet von aromatischen Aldehyden (Benzylidenaminoguanidine) wird beschrieben. Die Strukturzuordnung bei diesen Verbindungen sowie bei einigen literaturbeschriebenen Analoga — besonders im Hinblick auf die Konfiguration an der HC=N Doppelbindung — erfolgte mittels1H- und13C-NMR Spektroskopie sowie mit Hilfe homonuklearer NOE-Differenzspektroskopie.
  相似文献   

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