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1.
The13C NMR spectra have been investigated of a number of arylnaphthalene lignans of plant origin: daurinol and its acetyl derivative and reduction product, justicidin A, justicidin B and its reduction product and the diacetyl derivative of the reduction product, and diphyllin and its acetate. The values of the chemical shifts of the carbon atoms in the spectra of the compounds investigated and the nature of their change according to structural factors are discussed and an assignment is made of the resonance lines in the spectra. The characteristics of the spectrum of one compound are used as models for others. The parameters of the13C NMR spectra of a number of naphthalene derivatives are also used. On the basis of the results of the assignment of the signals, difference values of the chemical shifts of the carbon atoms in the series of compounds investigated have been determined. Using the experimental results as a background, some examples taken from the literature of investigations of the13C NMR spectra of related compounds have been analyzed.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 76–90, January–February, 1987.  相似文献   

2.
Two new glycosides of the cholestane series (allosides A and B) have been isolated from the fruit of the cocultivatedAllium suvorovii Rgi. andAllium stipitatum Rgl. (family Liliaceae, local name anzur). The acid hydrolysis of both compounds gave a sterol not previously described, which has been called alliosterol and has the structure of (22S)-cholest-5-ene-1, 3, 16, 22-tetraol, and the product of its dehvdration, which is (16S, 22S)-furost-5-ene-1, 3-diol. Alloside A is the 16-O--D-galactopyranoside, and alloside B the 16-O--D-galactopyranoside 1-O--D-glucopyranoside of alliosterol.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 231–241, March–April, 1991.  相似文献   

3.
In this study, it was found that in the thermal reaction of Z-3-methylpent-2-en-4-yn-1-ol, two parallel processes occur — radical polymerization and formation of low-molecular-weight products by a nonradical pathway. The structure of the principal low-molecular-weight product was determined. It was shown that its formation by dimerization of the original alcohol presented an unusual path-way for the Diels-Adler reaction with elimination of one molecule of formaldehyde from two molecules of alcohol.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2050–2052, September, 1989.The authors express their gratitute to A. F. Bochkov and A. B. Gagarinov for helpful discussions on the results of this work, and also to A. D. Pershin for recording the proton NMR spectra.  相似文献   

4.
Thermal decomposition of the [FeCp(SPh)CO]2 complex and its reaction with the surface of activated silica gel were investigated by Mössbauer spectroscopy. A small amount of a complex with properties similar to ferrocene is separated in the first stage of thermal decomposition (120–130°C). The starting carbonyl complex totally disappears in the second stage (165–210°C), and two compounds are present among the products: a derivative of ferrocene and the final product, an x-ray amorphous, iron-containing structure with an ionic-covalent type of chemical bond (CB) and a 25 and 5 wt. % concentration of oxygen and sulfur, respectively. The Mössbauer parameters of this product and the compound formed in the reaction of [FeCp(SPh)CO]2 with the surface of activated silica gel at 4.2–300 K are identical. The analysis of the data suggested that both structures are highly disperse clusters of iron oxide with the structure of an inverted spinel with superparamagnetic properties.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 771–778, April, 1991.We would like to thank Yu. B. Kopylovskii for assistance in processing the spectra with the MESLIN program.  相似文献   

5.
Aucubin and five substances of iridoid nature designated as A, B, C, D, and E have been isolated from two species of plants — Lagotis integrifolia (Willd.) Schisk and Incarvillea olgae (Rgl.). The IR, UV, mass, PMR and13C NMR spectra of substance A have been studied, and an x-ray structural investigation has been made of its tetrahydro derivative. This has shown that substance A is 7-benzoyltecomoside.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 61–69, January–February, 1995. Original article submitted November 1, 1994.  相似文献   

6.
On the basis of an analysis of the PMR spectra of flavons and its 3- and 5-hydroxy and methoxy derivatives by means of the method of paramagnetic additives, it is assumed that there are different relative orientations of the A, B, and C rings in flavone and its derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinehii, No. 11, pp. 1468–1471, November, 1974.  相似文献   

7.
Conclusions The principles of the reduction of 2-keto-derivatives of gibberellic acid by complex metal hydrides were studied, and the synthesis of the epimer of gibberellic acids and its ester was carried out.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1805–1809, August, 1969.The authors would like to thank V. I. Zaretskii and I. B. Papernaya for taking the mass spectra and discussing the results and A. V. Kessenikh for the NMR spectra.  相似文献   

8.
A new route is proposed for the synthesis of dodec-8E-enyl and dodec-8Z-enyl acetates which is based on the reaction of the Grignard reagent from the readily accessible 1-bromo-5-(1-ethoxyethoxy)pentane with 1-bromohept-3-yne — the bromide obtained from product of the -hydroxyethylation of pent-1-yne with 2-chloroethylvinyl ether, hept-3-yn-1-ol, by a double decomposition reaction of its tosylate with lithium bromide. The key synthon — dodec-8-yn-1-ol — was converted with the aid of sodium in liquid ammonia into the stereochemical individual dodec-8E-enol, while its reduction with the aid of 9-borabicyclo[3.3.1]nonane (BBN) gave the steroisomeric alcohol exclusively with the Z configuration, as followed from the results of capillary GLC and the IR spectra of the corresponding acetates. The PMR spectra of the compounds synthesized are also given.Institute of Chemistry, Bashkir Branch, Academy of Sciences of the USSR, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 398–400, May–June, 1985.  相似文献   

9.
The chemical properties of nitraramine have been studied. The possibility has been shown of the existence of the hydrolysis product in three tautomeric forms: aminoaldehyde, carbinolamine, and semiacetal. The NMR spectra of nitraramine and its derivatives (N-acetylnitraramine, dihydronitraramine) have been analyzed and this has permitted spatial structures to be suggested for these compounds.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 730–735, November–December, 1986.  相似文献   

10.
The Vilsmeier formylatlon of the cobalt complex of 5,10,15,20-tetraphenylporphyrin was realized, and its intermediate salt with the dimethylformamide-POC13 complex was isolated; demetallation of the latter gave 1-formyl-5,10,15,20-tetraphenylporphyrin. Formyltetraphenylporphyrin oxime and its 0-acetyl derivative and 1-cyano-5,10,15, 20-tetraphenylporphyrin were synthesized. The Wittig reaction with formylporphyrin and its copper and cobalt complexes with methoxycarbonylmethinyltriphenylphosphorane and diethylamidocarbonylmethinylhexamethyltriamidophosphorane was realized, and conditions that affect the ratios of the Z and E isomers of the acrylic derivatives obtained were studied.See [1] for Communication 13.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 59–64, January, 1982.The authors sincerely thank L. B. Lazukova and A. M. Shul'ge for recording the PMR spectra, V. P. Suboch for recording the mass spectra, and I. I. Mizrakhfor providing us with a sample of phosphorane B.  相似文献   

11.
Summary It has been established that the substance isolated previously fromInula germanica L. is a mixture of two new sesquiterpene lactones: germanin A and germanin B.On the basis of chemical reactions and a study of IR, UV, NMR, and mass spectra, structures (I) and (XVI), respectively, are proposed for germanin A and germanin B.All-Union Scientific-Research Institute of Medicinal Plants. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 578–589, September–October, 1974.  相似文献   

12.
13.
Conclusions The vibrational spectra of crystalline ethylenedinitramine, ethylenedinitramine labeled with N15, as well as their deutero-derivatives were studied. Assignment of the vibration frequencies of the nitramine fragment is proposed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2194–2197, October, 1969.The authors would like to thank B. Lokshin for recording the IR spectra in this region, as well as A. Bobrov for recording the Raman spectra.  相似文献   

14.
A combined analysis of two types of vibrational spectra (Raman and infrared) has proven the lactone structure of colorless solid preparations of phenolphthalein and thymolphthalein. It has been shown that phenolsulfophthalein, its alkyl derivatives, and bromcresol purple exist in the solid state primarily in the form of an intensely colored zwitterion; bromphenol blue and bromthymol blue exist primarily in the form of a colorless sultone. For the ionized forms of triphenylmethane dyes (cationic and anionic chromophore systems) vibrations with a frequency near 1360 cm–1 are characteristic in the IR spectra and also in the Raman spectra.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 26, No. 6, pp. 688–698, November–December, 1990.  相似文献   

15.
In this article we describe the composition of a library of molecular structures and evaluate its capabilities for modeling IR spectra of complicated compounds. A predictive calculation of an IR spectrum is performed for the molecule of 1-phenyl-4-(p-tolyl)-1,3-butadiene on the basis of the library of molecular structures, and the theoretical and experimental spectra of this molecule are compared.K. A. Timiryazev Agricultural Academy. Translated from Zhurnal Strukturnoi Khimii, Vol. 34, No. 1, pp. 197–201, January–February, 1993.  相似文献   

16.
In order to establish the interrelation between the electronic characteristics of carbons that are manifested in the EPR spectra and their ability to adsorb complex gold and silver ions, the EPR spectra of carbon adsorbents from phenol-formaldehyde resins of various nature, unactivated and activated under various conditions, and the adsorption of [Au(CN)2] and [Ag(CN)2] from cyanide solutions on these same adsorbents were investigated. A parallel relation was observed between the amount of paramagnetic centers on carbon and its adsorption capacity and selectivity in relation to these anions.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 26, No. 6, pp. 742–745, November–December, 1990.  相似文献   

17.
The field desorption mass spectra (FD spectra) of 17 natural flavonoid acetylglycosides have been studied. In the spectra of each of the 0-monoglycosides the molecular ion (M or M + H) appears as the main peak and it is accompanied by the ions of the aglycone (A or A + H) and of the acylated anhydrosugar (S). The intensity of the latter peak is largely connected with the structure of the substance. In the FD spectra of flavone 0-biosides, fragment S is absent but its mass can be calculated from the difference (M – A). Useful information for establishing the position of the acetyl group is given by the fragments S1 and (M – S1) corresponding to the detachment of the terminal sugar residue. The FD spectra of flavone C-glycosides differ greatly from the spectra of the 0-glycosides: In them the main peak is that of the ion (M), but peaks (A) and (S) are absent and the ions present resemble the fragmentation of the C-glycosides under the action of electron impact.All-Union Scientific-Institute of Medicinal Plants, Moscow. L. Ya. Karpov Scientific-Research Institute of Physical Chemistry, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 573–582, September–October, 1984.  相似文献   

18.
The B/E linked scanning spectra of the M+, (M-15)+, and (M-OR1)+ ions and those of some other series have been investigated. The characteristic nature of the individual intensities of the metastable peaks (the magnitudes A) with the same R1 radicals for different groups of alkaloids has been shown for the spectra of the M+ and (M-15)+ ions. The reason for the quantitative differences of the B/E spectra of the (M-OH)+ ions from the spectra of the (M-OCH3)+ and (M-OAc)+ ions, consisting in the influence of alternative methods of eliminating an OH radical, has been found. It has been confirmed that the values of A of analogous transitions calculated from the B/E and MD spectra are close to one another. On the other hand, the values of the energy of the metastable transitions obtained by these two methods differ from one another by two orders of magnitude.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Special Design Bureau of Analytical Instrument Construction, Scientific and Technical Branch, Academy of Sciences of the USSR, Leningrad. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 72–84, January–February, 1991.  相似文献   

19.
A new effective method of synthesizing fragment 1–4 of the ACTH sequence ensuring a high overall yield of the desired product is proposed. This result is achieved thanks to the wide use of the silylation reaction in the synthesis, which has permitted a considerable simplification of the process and the avoidance of the formation of by-products. The peptides synthesized have been characterized by their angles of optical rotation, chromatographic mobilities, and melting points. A table of chemical shifts in the13C NMR spectra of the final and intermediate compounds is given.All-Union Research Institute of Technology of Blood Substitutes and Hormone Preparations, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 248–253, March–April, 1988.  相似文献   

20.
The atropodiastereomeric dimeric naphthylisoquinoline alkaloids, michellamines A (1a), B (1b) and C (1c), together with their monomers, korupensamines A (2a) and B (2b), were investigated using electrospray ionization tandem mass spectrometry coupled to liquid chromatography (LC–ESI-MS–MS). From the spectra obtained, characteristic product ions were chosen to monitor the chromatographic separation achieved on an RP-18 column. Under acidic conditions required for chromatographic analysis, the monomeric alkaloids 2a and 2b yielded protonated molecules [M+H]+, while the dimers, the michellamines, exhibited doubly protonated [M+2H]2+ molecules. In addition, the coeluting alkaloids 1b and 2b were identified unambiguously by means of tandem mass spectrometry. Thus, together with the retention times of the alkaloids, the product ion spectra allowed us the identification of michellamines in the presence of their presumed biogenetic monomeric precursors. Application of the HPLC–MS–MS method successfully proved the enzymatic formation of michellamine C (1c) by in vitro dimerization of korupensamine B (2b).  相似文献   

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