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N. K. Ostrovskaya A. F. Mironov R. P. Evstigneeva N. A. Preobrazhenskii 《Chemistry of Heterocyclic Compounds》1969,5(4):470-473
A method is proposed for the synthesis of porphyrins based on the cyclization of a tetrapyrrole system with methyl and formyl groups at the ends of the molecule. The synthesis of mesoporphyrin IX and diacetyldeuteroporphyrin IX has been effected. 相似文献
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V. M. Mamaev G. V. Ponomarev R. P. Evstigneeva 《Chemistry of Heterocyclic Compounds》1970,4(2):198-199
The positions of the electronic absorption bands and also the intensities of the Soret bands of the porphyrins with ethoxycarbonyl substituents in the form of dications have been calculated by the LCAO MO method in Huckel's approximation. Comparison with the experimental results shows good agreement. 相似文献
5.
In the interaction of ethioporphyrin and of several of its metal derivatives with negative ions of pyridine and anthracene in tetrahydrofuran solutions, an electron transfer takes place which results in the conversion of the pyridine and anthracene ions into neutral molecules, whereas the molecules of the pigment are first transformed into monovalent anions and subsequently into the di-, tri-, tetra-, and sometimes even into the hexavalent anions. In the first stage of this interaction, ferriethioporphyrin is reduced to ferro-ethioporphyrin, whereas the unmetallized pigment and its copper complex are transformed into the disodium derivative of ethioporphyrin. When the temperature is lowered, the rate of the electron transfer from pyridine ions to zinc-ethioporphyrin is decreased, and illumination leads to a substantial rate increase. The photochemical sensitivity of this system is possibly linked to the formation of stable complexes between pigment molecules and pyridine ions. 相似文献
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V. D. Gusev T. K. Mitrofanova O. N. Tolkachev R. P. Evstigneeva 《Chemistry of Natural Compounds》1974,8(1):6-9
Summary 1. The condensation of the anomeric methyl 2,3-di-O-benzyl-D-xylofuranosiduronaldehydes with nitromethane has been studied.2. It has been shown that the position of the substituent at the glycosidic center has an influence on the steric directivity of this reaction.3. The structure of the 6-nitro-6-deoxyhexofuranosides synthesized has been confirmed by their conversion into known derivatives of methyl D-glucofuranosides.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 8–12, January–February, 1972. 相似文献
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Evstigneeva R. P. Luzgina V. N. Timashev P. S. Ol'shevskaya V. A. Zakharkin L. I. 《Russian Journal of General Chemistry》2003,73(10):1648-1652
Basing on protoporphyrin IX, its monobenzyl ester, deuteroporphyrin IX, 9-hydroxymethyl-m- and 9-hydroxymethyl-p-carboranes, mono- and dicarborane-containing porphyrins were prepared. 相似文献
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Yu. E. Sklyar R. P. Evstigneeva N. A. Preobrazhenskii 《Chemistry of Heterocyclic Compounds》1969,5(1):58-60
The condensation of isonitrosoacetylacetone with 3-alkyl-2,4-pentanediones and reduction with zinc in acetic acid gives-acetyltrialkylpyrroles. The analogous condensation of 3-alkyl-3-nitroso-2,4-pentanediones with acetylacetone leads to-acetyltrialkylpyrroles, and condensation with acetoacetic ester leads to-ethoxycarbonyltrialkylpyrroles. When the- and-acetyltrialkylpyrroles undergo salt formation, the oxygen of the carbonyl group is protonated. 相似文献
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Summary The synthesis of a nonapeptide, the benzyl ester of N-benzyloxycarbonyl-S-benzyl-L-cysteinyl--benzyl-L-glutamyl-L-leucyl-S-benzyl-L-cysteinyl-Nim-benzyl-L-histidyl-L-threonyl-L-valyl--benzyl-L-glutamyl-N-tosyl-L-lysine (XIII), and a heptapeptide, the benzyl ester of N-benzyloxycarbonyl-N-tosyl-L-lysyl-L-threonyl-nitro-L-arginyl-S3-benzyl-L-cysteinyl--methyl-L-glutamyl-L-leucyl-S-benzyl-L-cysteine (VII), corresponding to the sequences 14–22 and 11–17 of yeast cytochrome c, has been effected.M. V. Lomonosov Moscow Institute of Fine Chemical Technology. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 474–480, July–August, 1971. 相似文献