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1.
The interaction of 3,5-diamino-4-nitropyrazole with such electrophilic reagents as acetic anhydride, dimethylformamide acetal, orthoformic ester, and ketones has been studied. Derivatives of pyrazolol[1,5-a]pyrimidines were formed on reaction with 1,3-diketones and some of their properties have been studied.Center for Drug Chemistry, All-Russian Chemical and Pharmaceutical Research Institute (VNIKhFI), Moscow 119815. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 329–335, March, 1997. 相似文献
2.
The reaction of -cyano--aminocrotonic ester with DMFA diethylacetal gives 1-ethoxycarbonyl-1-cyano-2-(N-dimethylaminomethylene)-amino-4-dimethylaminobutadiene, the reaction of which with ammonium acetate and amines leads to 4-methylenepyrimidine derivatives. Condensation of -cyano--aminocrotonic ester with dimethylacetamide dieethylacetal gave 2-(ethoxycarbonylcyano)methylene-4-dimethylamino-6-methylpyridine. It was found that in an alkaline medium, 1-benzyl-4-(ethoxycarbonylcyano) methylenepyrimidine recyclizes into 1-benzyl-3-cyano-4-amino-2-pyridone.For Communication 52, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1109–1114, August, 1988. 相似文献
3.
N. I. Mikerova L. M. Alekseeva E. K. Panisheva Yu. N. Sheinker V. G. Granik 《Chemistry of Heterocyclic Compounds》1990,26(3):274-278
The reaction of 2-chloro-5-methylbenzoquinone with -aminocrotonic ester derivatives was studied by PMR spectroscopy in CD3COOD. The spectra indicate the formation of intermediate hydroquinone and quinone derivatives, which subsequently transform into the corresponding indoles. It was shown that the indolization proceeds unequivocally at the 3-position of the initial benzoquinone, and the rate of formation of the indole derivatives decreases with increase in the size of the substituent at the nitrogen atom of the -aminocrotonic ester. The starting, intermediate compounds and the end products observed in the PMR spectra were identified by comparison with specially synthesized compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 324–328, March, 1990. 相似文献
4.
V. A. Makarov A. L. Sedov O. S. Anisimova V. G. Granik 《Chemistry of Heterocyclic Compounds》1996,32(6):699-707
Highly polarized enediamines of the a, -diamino--cyano--nitroethylene type have been obtained by the hydrolysis of 4-chloro-5-nitropyrimidines. Several chemical conversions of the enamines obtained have been studied, particularly leading to derivatives of 2-(cyanonitromethylene)imidazoline and -hexahydropyrimidine, and also to derivatives of N, N-bisvinylpiperazine and 7 methylene-1, 4-diazabicyclo(2.2. 1 ]heptane.Center for Drug Chemistry, All-Russian Chemical and Pharmaceutical Research Institute, Moscow 119815. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 811–820, June, 1996. Original article submitted February 6, 1996.For Part 1, see [1]. 相似文献
5.
The synthesis of 2,3,5,6-tetrahydropyrrolo[3,2-c]pyrid-6-one was accomplished by rearrangement of 8H,1-cyano-8-dimethylaminomethylene-2,5,6,7-tetrahydropyrrolo[1, 2-c]pyrimidine. Pyrrolo[3,2-c]pyrimidine, 1,6-naphthyridine, and pyrimido[4,3-b]-azepine derivatives were synthesized on the basis of enamino dinitriles. The hydrolysis of 8H,1-cyano-8-dimethylaminomethylene-2,5,6,7-tetrahydropyrrolo[1,2-c]-pyrimidine in 50% CH3COOH leads to a pyrrolo[1,2-c]pyrido[4,3-d]pyrimidine derivative. A similar dipyrido[4,3-d-1,2-c]pyrimidine derivative was obtained from 1-cyano-9-dimethylaminomethylene-2,5,6,7,8,9-hexahydropyrido[1,2-c]pyrimidine under these conditions, and 3,4-dioxo-3,4,7,8,9,10-hexahydropyrido[1,2-c]pyrano[4,3-d]-pyrimidine was synthesized bytreatment with a 1 N solution of HCl.See [1] for Communication 34.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 518–522, April, 1982. 相似文献
6.
V. M. Lyubchanskaya L. M. Alekseeva V. G. Granik 《Chemistry of Heterocyclic Compounds》1992,28(1):34-39
Previously unknown 3-nitro-6-hydroxyindole derivatives were synthesized by condensation of p-benzoquinone with secondary -nitro enamines.See [1] for Communication 70.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 40–45, January, 1992. 相似文献
7.
V. G. Granik 《Chemistry of Heterocyclic Compounds》1992,28(6):632-647
The review collects the results of investigations on the synthesis of heterocyclic compounds, mainly azaheterocycles, from amide and lactam acetals. The reasons for the high reactivity of these compounds with respect to nucleophilic and electrophilic reagents are considered, as are the principal pathways of heterocyclization of amidine and enamine systems synthesized via amide and lactam acetals.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 762–780, June, 1992. 相似文献
8.
The review considers problems related to the formation, in the living organism, of nitric oxide, a versatile and vitally important regulator of cell metabolism. The pathways of formation of endogenous nitric oxide from L-arginine are discussed and the main approaches to increasing the NO concentration by introducing various types of exogenous nitric oxide donors into the organism and chemical and biological characteristics of these donors are considered. Primary attention is devoted to the known drugs that were shown to release NO under hydrolytic, oxidative, or reductive conditions. The solution of problems related to the elucidation of the mechanisms of drug action requires that the formation of nitric oxide be taken into account. 相似文献
9.
S. Yu. Kukushkin P. Yu. Ivanov L. M. Alekseeva V. I. Levina K. I. Kobrakov N. B. Grigor'ev V. G. Granik 《Russian Chemical Bulletin》2005,54(8):1887-1891
The half-wave potentials of polarographic reduction of the carbonyl group in unsubstituted and N-methyl- and N-phenylsulfonyl-substituted 1- and 4-oxotetrahydrocarbazoles and their reactivities in reactions with nucleophilic (NaBH4, malonodinitrile, and cyanoacetamide) and electrophilic (DMF dimethyl acetal) reagents were compared. 4-Oxotetrahydrocarbazoles
are much less reactive than 1-oxotetrahydrocarbazoles.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1832–1836, August, 2005. 相似文献
10.
Ryndina S. A. Kadushkin A. V. Solov"eva N. P. Granik V. G. 《Russian Chemical Bulletin》2002,51(5):854-859
Approaches to the synthesis of 3-aminothiophene-2,4-dicarboxylic acid derivatives and to their conversions into thieno[3,4-d]pyrimidines, thieno[3,4-d]-1,2,3-triazines, and thieno[3,2-d]pyrimidines are developed. 相似文献