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1.
A. N. Kost R. S. Sagitullin G. G. Danagulyan 《Chemistry of Heterocyclic Compounds》1978,14(10):1139-1144
It is shown that 2-alkylpyrimidine methiodides in which the alkyl group is activated by electron-acceptor substituents undergo recyclization to the corresponding 2-methylaminopyridines in an alcohol solution of methylamine. Similar recyclization also takes place without quaternization of the pyrimidine ring when there is a strong electron-acceptor substituent (a nitro group) in the ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1400–1405, October, 1978. 相似文献
2.
G. G. Danagulyan D. A. Tadevosyan F. S. Kinoyan 《Chemistry of Heterocyclic Compounds》2006,42(6):782-787
Intermediate recyclization products were obtained in a study of the Kost-Sagitullin rearrangement of a series of 1,2-dialkylpyrimidinium
iodides. The initial attack of the nucleophile leads to the formation of products of the addition of the hydroxyl group, namely,
the corresponding pseudo bases. Heating one of these intermediates in ethanol or in the presence of primary amines leads to
rearrangement to give a pyridone derivative. Upon heating in chloroform, the pseudo bases readily lose a water molecule and
are converted to anhydro bases, namely, derivatives of 1-alkyl-1,2-dihydro-2-methylidenepyrimidine.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 894–900, May, 2006. 相似文献
3.
G. G. Danagulyan G. A. Panosyan L. G. Sahakyan 《Chemistry of Heterocyclic Compounds》2007,43(8):996-1000
The interaction of the iodomethylates of pyrimidinyl-2-acetic acid derivatives with monosubstituted hydrazines, in addition
to the products of a Kost-Sagitullin rearrangement, leads also to N-substituted triazoles. The structure of the triazoles
was demonstrated by NOESY NMR experiments. The structure of the reaction products was determined on the basis of the response
observed in the spectra between the methyl group protons of the triazole ring and the spatially close proton of the substituent
in position 1 and a conclusion was drawn on the direction of the primary attack of nucleophile in the recyclization process
of the pyrimidinium salts into a 1,2,4-triazole.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1175–1179, August, 2007. 相似文献
4.
G. G. Danagulyan A. D. Mkrtchyan G. A. Panosyan 《Chemistry of Heterocyclic Compounds》2005,41(4):485-491
Condensation in ethanol of ethyl ethoxymethyleneacetoacetate with systems containing an amidine fragment (substituted 3-aminopyrazoles and 3-amino-1,2,4-triazole) gave 6-carbethoxy-7-methylpyrazolo[1,5-a]pyrimidines. Addition of base to solutions of the obtained bicyclic carbethoxy derivatives in the course of several minutes caused rearrangement to 6-acetyl-7-hydroxypyrazolo[1,5-a]pyrimidine and 6-acetyl-7-hydroxy-1,2,4-triazolo[1,5-a]pyrimidine respectively. A more prolonged refluxing in 15% aqueous alcohol solution of base caused 6-carbethoxy-7-methyl-2-phenylpyrazolo[1,5-a]pyrimidine and 6-acetyl-7-hydroxy-2-phenylpyrazolo[1,5-a]pyrimidine to recyclize to 7-methylpyrazolo[1,5-a]pyrimidine.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 569–576, April, 2005. 相似文献
5.
6.
The rearrangement of 1-alkyl-2-(carbamoylmethyl)pyrimidinium iodides into substituted 2-alkylaminonicotinamides occurring in alcoholic solutions of amines has been studied. It was shown that in the presence of water the rearrangement of 2-(carbamoylmethyl)-1,4,6-trimethylpyrimidinium iodide is accompanied by the formation of a derivative of 2-oxo-1,2-dihydronicotinic acid, and under the action of ethylamine a rearrangement and transamination occurs leading to 2-ethylamino-4,6-dimethylnicotinamide. 相似文献
7.
8.
A. R. Balabekyan A. S. Danagulyan J. R. Drnoyan G. H. Hovhannisyan J. Adam V. G. Kalinnikov M. I. Krivopustov V. S. Pronskikh V. I. Stegailov A. A. Solnyshkin P. Chaloun V. M. Tsoupko-Sitnikov S. G. Mashnik K. K. Gudima 《Physics of Atomic Nuclei》2006,69(9):1485-1495
We measure cross sections for residual nuclide formation in the mass range 7 ≤ A ≤ 96 caused by bombardment with protons and deuterons of 3.65-GeV/nucleon energy of enriched tin isotopes (112,118,120,124Sn). The experimental data are compared with calculations by the codes FLUKA, LAHET, CEM03, and LAQGSM03. Scaling behavior
is observed for the whole mass region of residual nuclei, showing a possible multifragmentation mechanism for the formation
of light products (7 ≤ A ≤ 30). Our analysis of the isoscaling dependence also shows a possible contribution of multifragmentation to the production
of heavier nuclides, in the mass region 40 ≤ A ≤ 80.
The text was submitted by the authors in English. 相似文献
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