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1.
L. A. Ignatova A. E. Gekhman P. L. Ovechkin B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1974,10(3):307-309
3,4,4,6-Tetramethyl-2-aryliminotetrahydro-1,3-oxazines were synthesized by intramolecular cyclization of N-aryl-N′-methyl-N′-(2-methyl-4-hydroxy-2-pentyl)-S-methylisothioureas. 4,4,6-Trimethyl-2-(N-methyl-N-arylamino)-5,6-dihydro-4H-1,3-oxazines were obtained by methylation of 4,4,6-trimethyl-2-arylamino-5,6-dihydro-4H-1,3-oxazines. 相似文献
2.
P. L. Ovechkin L. A. Ignatova B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1972,8(7):856-858
The synthesis of 3,4,4,6-tetramethyl-2-arylimino-2,3-dihydro-4H-1,3-thiazines, which have a fixed imino structure, was accomplished by two methods: by intramolecular rearrangement of 1,4,6,6-tetramethyl-3-aryl-1,2,3,6-tetrahydropyrimidine-2-thiones and by amination of 3,4,4,6-tetramethyl-2,3-dihydro-4H-1,3-thiazine-2-thione methiodide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 941–943, July, 1972. 相似文献
3.
B. V. Unkovskii I. P. Boiko Yu. F. Malina T. D. Sokolova V. F. Shchegel'skii L. N. Knyaz'kova 《Chemistry of Heterocyclic Compounds》1992,28(10):1225-1228
The reaction of phenyl isothiocyanate with 1,3-amino alcohols was used to synthesize substituted N-phenylthioureas, for which cyclization under the influence of mineral acids to give substituted 5,6-dihydro-4H-1, 3-thiazines was studied.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1433–1437, October, 1992. 相似文献
4.
E. M. Peresleni L. A. Ignatova P. L. Ovechkin A. P. Engoyan Yu. N. Sheinker B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1975,11(12):1370-1374
It is shown by means of the IR, UV, and PMR spectra of substituted 2-amino-4H-1,3-thiazines that they exist primarily in the amino form in the crystalline state and in solution. 相似文献
5.
L. A. Ignatova P. L. Ovechkin A. E. Gekhman B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1976,12(12):1333-1336
The relative basicities of 4,4,6-trimethyl-2-arylamino-5,6-dihydro-4H-1,3-thiazines and 4,4,6-trimethyl-2-arylamino-5, 6-dihydro-4H-1,3-oxazines, which are capable of amine-imine tautomerism, and of model compounds with fixed amine and imine structures were determined by potentiometric titration in methanol. Good correlation of the pK
a
values with the Hammett constants in the investigated reaction series was found. The inapplicability of the use of the pK
a
values of model compounds for the determination of the tautomeric equilibrium constants in the case of some N-heterocyclic amines of nonaromatic character with an aryl substituent attached to the exocyclic nitrogen atom of the amidine fragment of the molecule is demonstrated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1621–1624, December, 1976. 相似文献
6.
Several allylic isothiuronium salts 6 have been shown to yield 4-substituted 2-amino-5,6-dihydro-4H-1,3-thiazines ( 2 ; R3 = H) and the 2-phenylimino compound 10 on exposure to trifluoroacetic acid or trifluoroacetic acid-stannic chloride. The overall process constitutes a convenient transformation of readily available ketones or aldehydes 3 into the target hetero-cycles. The scope and limitations of this approach are discussed in terms of carbenium ion intermediates ( 7 ). Whereas this method successfully led to the imidazo[2,l-b][1,3]thiazine 13 (93% from 12 ), its application to the synthesis of 2-amino-2-thiazolines (eg. 14 → 15 ) or imidazo-[2,1-b]thiazoles (eg. 16 → 17 ) was unsuccessful. The 2-acetylimino derivatives 9 were found to be useful for purification of the 2-aminothiazines. 相似文献
7.
Peresleni E. M. Engoyan A. P. Zotova T. D. Sheinker Yu. N. Ignatova L. A. Unkovskii B. V. 《Chemistry of Heterocyclic Compounds》1977,13(3):278-284
It is shown by means of IR, PMR, and UV spectra that 4,4,6-trimethyl-2-arylamino-5, 6-dihydro-4H-1,3-thlazines and 4,4,6-trimethyl-2-arylamino-5,6-dihydro-4H-1,3-oxazines in the crystalline state and in solution exist primarily in the amino form. It was found that ionization to give cations proceeds more readily in the case of 1,3-oxazines than in the case of 1,3-thiazines. In addition, a decrease in the ability to undergo intermolecular association and a decrease in the energy barrier to rotation about the N-heteroring bond are observed for 1,3-oxazines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 346–352, March, 1977. 相似文献
8.
The reaction of 4-alkoxytetrahydro-1, 3-thiazine-2-thiones with methyl iodide and subsequent treatment of the resultant S-alkylation products by suitable sodium alcoholates yielded 4-alkoxy-2-methylthio-S, 6-dihydro-4H-1, 3-thiazines, which upon reaction with phenoxyacetyl chloride in the presence of triethylamine was stereospecifically converted into 4-alkoxy-6-methylthio-7-phenoxvcephams.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 557–560, April, 1996. 相似文献
9.
L. A. Ignatova A. E. Gekhman M. A. Spektor P. L. Ovechkin B. V. Unkovskil 《Chemistry of Heterocyclic Compounds》1974,10(6):662-665
4,4,6-Trimethyl-2-methylarylamino-4H-1,3-oxazines were synthesized by intramolecular cyclization of N-oxoalkyl-S-methylisothioureas.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 764–767, June, 1974. 相似文献
10.
P. L. Ovechkin L. A. Ignatova B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1971,7(7):882-885
A comparison of the IR and UV spectra of 2-alkyl(aralkyl)amino-4H-1,3-thiazines with the spectra of model compounds showed that the amino form of the aminothiazines predominates. The basicities of the synthesized compounds were determined, and the structure of the cation formed on protonation is discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii. No. 7, pp. 946–949, July, 1971. 相似文献
11.
2-Methylthio-4H-1,3-thiazines or their mixtures with 5-alkylidene-4H-5,6-dihydro-1,3-thiazines were obtained by cyclization of methyl N-3-oxoalkyldithiocarbamates in sulfuric acid. The regiospecificity of the reaction is determined by the structures of the starting compounds. The structures of the synthesized thiazines were confirmed by spectral methods of analysis (IR and 1H and 13C spectroscopy).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 991–993, July, 1992. 相似文献
12.
L. A. Ignatova P. L. Ovechkin M. Z. Branzburg A. E. Gekhman B. V. Unkovskii 《Chemistry of Heterocyclic Compounds》1972,8(8):939-942
4,4,6-Trimethyl-2-alkyl(aryl)amino-5,6-dihydro-4H-1,3-oxazines were synthesized via two methods: amination of 4,4,6-trimetiiyl-2-methylthio-5,6-dihydro-4H-1,3-oxazine and cyclization of N-aryl-N-(2-methyl-4-hydroxy-2-amyl)-S-methylisothiourea.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1037–1040, August, 1972. 相似文献
13.
14.
T. P. Trofimova O. N. Zefirova A. A. Mandrugin V. M. Fedoseev D. I. Peregud M. V. Onufriev N. V. Gulyaeva S. Ya. Proskuryakov 《Moscow University Chemistry Bulletin》2008,63(5):274-277
The synthesis and results of in vitro and in vivo testing of 2-N-acetylamino-, 2-N-benzoylamino-,2-N-cyclohexanecarbonylamino-, and 2-N-(1-adamantanecarbonyl)amino-5,6-dihydro-4H-1,3-thiazines for NOS-inhibiting activity have been described. 相似文献
15.
B. S. Fedorov M. A. Fadeev V. V. Arakcheeva G. V. Strukov N. I. Golovina R. F. Trofimova G. V. Shilov L. O. Atovmyan 《Russian Chemical Bulletin》1994,43(12):2087-2090
A novel heterocyclic compound, 4-acetoxy-5,6-dihydro-5,5-dinitro-2H-1,3-oxazineN-oxide, has been synthesized by the reaction of the dipotassium salt of 1,1,5,5-tetranitro-3-oxapentane with aqueous acetic acid. The synthesized compound has been studied by X-ray diffraction analysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2207–2210, December, 1994.We would like to thank G. V. Lagodzinskaya (Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences) for recording and interpreting1H NMR spectra, A. M. Korolev (Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences) for helpful discussion, and V. I. Fetisov (Institute of Physiologically Active Compounds, Russian Academy of Sciences) for performing quantum-chemical calculations by the AM1 SCF MO LCAO method. 相似文献
16.
A method was developed to prepare 1,3-chloroisothiocyanatoalkanes by reducing 1,3-isothiocyanato ketones using sodium borohydride at pH ~7 and subsequent treatment of the resultant 1,3-isothiocyanato alcohols with thionyl chloride. The reaction of 1,3-chloroisothiocyanatoalkanes with sodium hydrosulfide or amines gives substituted tetrahydro-1,3-thiazine-2-thiones or 2-amino-5,6-dihydro-1,3-thiazines. 相似文献
17.
Demchenko A. M. Bova S. I. Chumakov V. A. Krasovskii A. N. Rusanov E. B. Chernega A. N. Lozinskii M. O. 《Russian Journal of General Chemistry》2001,71(11):1759-1763
Substituted phenacyl bromides react with 2-anilino-5,6-dihydro-4H-1,3-thiazine at the exocyclic nitrogen atom and with 2-benzylamino-5,6-dihydro-4H-1,3-thiazine at the nitrogen atom in the ring. The structure of the reaction intermediates was elucidated, and their cyclization into 1-benzyl-2-aryl-6,7-dihydro-5H-imidazo[2,1-b][1,3]thiazinium bromides was performed. 相似文献
18.
P. A. Sharbatyan A. T. Lebedev V. G. Kartsev A. M. Sipyagin 《Chemistry of Heterocyclic Compounds》1981,17(1):34-38
Under the influence of electron impact, 2-aryl-1,3-oxazin-5-ones undergo fragmentation primarily with the elimination of the C2H2O2 group of atoms, as well as with the formation of aroyl cations. The complete absence of the retrodiene fragmentation that is characteristic for such heterocyclic systems makes it possible to conclude that the double bond in the heteroring is not stabilized. In the case of 4-alkyl- and 4-benzyl-substituted oxazinones the molecular ions under-go rearrangement, as a result of which a seven-membered heteroring is formed due to inclusion of the methylene group of the substituent in an oxazine ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 43–47, January, 1981. 相似文献
19.