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2.
Pryadeina M. V. Burgart Ya. V. Suslova K. I. Saloutin V. I. 《Russian Chemical Bulletin》2002,51(9):1727-1730
4-Acyl(alkoxycarbonyl)-5-fluoroalkyl-3,5-dihydroxyfuran-2(5H)-ones were obtained for the first time by the reactions of fluoroalkyl-containing 1,3-diketones and 3-oxo esters with oxalyl chloride. 相似文献
3.
I. B. Dzvinchuk A. N. Chernega M. O. Lozinskii A. A. Tolmachev 《Chemistry of Heterocyclic Compounds》2008,44(6):682-689
2-(3,6-Diaryl-2,5-dihydropyridazin-4-yl)-1H-benzimidazoles undergo a previously unknown type of recyclization of the pyridazine
ring to a pyrazole to give 2-[(3,5-diarylpyrazol-4-yl)methyl]-1H-benzimidazoles. It is suggested that the mechanism of this
conversion, which includes formation of a secondary enhydrazine group in the diazine ring and its subsequent contraction,
occurs after the intramolecular formation and opening of a cyclopropane ring.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 853–861, June, 2008. 相似文献
4.
Nataliya S. Goulioukina 《Tetrahedron》2011,67(49):9535-9540
Diazoalkanes regiospecifically react with dimethyl 1-(formylamino)ethylenephosphonate (1a) to afford 5-substituted dimethyl 3-(formylamino)-4,5-dihydro-3H-pyrazol-3-phosphonates 2 in high yields. Their thermal decomposition followed by hydrolysis provides a straightforward access to 2-substituted 1-aminocyclopropanephosphonic acids 4. Aromatization of 2 under acidic conditions leads to 3-phosphorylated pyrazoles 5. 相似文献
5.
The (13)C and (15)N CPMAS NMR spectra of 18 pyrazoles substituted at position 1 by dinitrophenyl and trinitrophenyl (picryl) groups have been recorded. To help in the assignments, some of these compounds were studied in DMSO-d(6) solution. Phenomena such as the conformation of the N-aryl groups and broadening of splittings due to quadrupolar nuclei are discussed. 相似文献
6.
The higly stereoselective nitrilimine cycloaddition onto the novel 3(R*)-phenyl-4(S*)-cinnamoyl-2-azetidinone 2 gave 4-(4,5-dihydropyrazol-5-yl)carbonyl-2-azetidinone 5 as the major product and 4-(4,5-dihydropyrazol-4-yl)carbonyl-2-azetidinone 6 as the minor one. Ceric ammonium nitrate (CAN) oxidation of the cycloadducts gave the title compounds with good overall yield. 相似文献
7.
G. V. Bozhenkov G. G. Levkovskaya A. N. Mirskova L. I. Larina 《Chemistry of Heterocyclic Compounds》2005,41(7):854-860
A method has been developed for obtaining 3-alkyl(phenyl)-4(5)-chloro-1-(2,4-dinitrophenyl)pyrazoles from appropriate dinitrophenylhydrazones
of 1-chloro-, 1,2-, and 2,2-dichlorovinyl ketones by heating the latter in polyphosphoric acid. The structure of the pyrazoles
was studied by IR and 1H NMR spectroscopy.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1012–1019, July, 2005. 相似文献
8.
I. B. Dzvinchuk A. M. Nesterenko M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2008,44(2):190-196
Treatment of 1,4-diaryl-2-(1H-benzimidazol-2-yl)butane-1,4-diones with hydrazine gives the previously unknown 2-(3,6-diaryl-2,5-dihydropyridazin-4-yl)-1H-benzimidazoles
which are aromatized by oxidation with nitrous acid to give 2-[3,6-diarylpyridazin-4-yl]-1H-benzimidazoles.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 252–259, February, 2008. 相似文献
9.
Condensation of 3-[(3-hydrazino-3-oxopropyl)anilino]-and 3-[(3-hydrazino-3-oxopropyl)-4-methylanilino]propane hydrazides with
2,4-pentanedione, phenyl isocyanate or phenyl isothiocyanate (with subsequent work up of the semicarbazides obtained by base),
and carbon disulfide gave respectively: 1-(3,5-dimethyl-1H-1-pyrazolyl)-3-[3-(3,5-dimethyl-1H-1-pyrazolyl)-3-oxopropylanilino]-1-propanone,
3-(2-{[2-(5-oxo-4-phenyl-4,5-dihydro-1H-1,2,4-triazol-3-yl)ethyl]anilino}ethyl)-4-phenyl-4,5-dihydro-1H-1,2,4-triazol-5-one
and its thio analog, and 5-(2-{[2-(2-thioxo-2,3-dihydro-1,3,4-oxadiazol-5-yl)ethyl]anilino}ethyl)-2,3-dihydro-1,3,4-oxadiazole-2(3H)-thione
plus their methyl derivatives.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1353–1358, September, 2007. 相似文献
10.
T. V. Shokol V. V. Semenyuchenko V. P. Khilya 《Chemistry of Heterocyclic Compounds》2005,41(5):673-678
By recyclization of 2-R-6-ethyl-7-hydroxy(methoxy)-3-(5-phenyl-1,3,4-thiadiazol-2-yl)chromones when treated with hydrazine hydrate and phenylhydrazine, we synthesized 5-phenyl-2-(3-R-5-R1-1H-pyrazol-4-yl)-1H-1,3,4-thiadiazoles and 2-(3-R-5-R1-1-phenyl-1H-pyrazol-4-yl)-5-phenyl-1H-1,3,4-thiadiazoles. We confirmed the structure of the latter from 1H NMR spectra.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 781–787, May, 2005. 相似文献
11.
V. V. Arkhipov M. M. Garazd M. N. Smirnov V. P. Khilya 《Chemistry of Heterocyclic Compounds》2004,40(2):183-187
3-Aryloxychromones are recyclized under the action of hydrazine into derivatives of 4-aryloxy-3-(2,4-dihydroxyphenyl)pyrazole. 相似文献
12.
Hans Hilpert 《Helvetica chimica acta》1987,70(5):1307-1311
Synthesis of 3-(2-Carboxy-4-pyridyl)-and 3-(6-Carboxy-3-pyridyl)-DL-alanine As starting materials for potential photochemical approaches to betalaines C(R = COOH) and to muscaflavine F(R = COOH), β-(2-carboxy-4-pyridyl)- and β-(6(carboxy-3-pyridyl))-DL-alanine ( A and D with R = COOH or 4 and 11 ), respectively, were prepared (Scheme 1). The synthesis of 4 (= A, R = COOH) started with the 2-[(4-pyridyl)methyl]malonate 1 and proceeded via the N-oxide 2 , cyanation and hydrolysis (Scheme 2). Amino acid 11 was obtained from (3-pyridyl)methyl-bromide ( 6 ) via the malonate 7 by an analogous sequence of reactions (Scheme 3). 相似文献
13.
E. V. Shchegol’kov Ya. V. Burgart O. G. Khudina V. I. Saloutin O. N. Chupakhin 《Russian Chemical Bulletin》2004,53(11):2584-2590
Fluoroalkyl-containing 1,2,3-triketone 2-(2,3-dimethyl-5-oxo-1-phenyl-1,2-dihydropyrazol-4-yl)-, 2-(4-ethoxycarbonylpyrazol-3-yl)-, and 2-(1,2,4-triazol-3-yl)hydrazones were synthesized by the azo coupling reactions of fluorinated 1,3-diketones with the corresponding hetaryldiazonium chlorides. The hetarylhydrazones thus synthesized were subjected to cyclocondensation with hydrazines at the 1,3-dicarbonyl fragment to give 3-fluoroalkyl-4-hetarylazopyrazoles.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2478–2483, November, 2004. 相似文献
14.
MURTAZA MADNI SHAHID HAMEED MUHAMMAD NAEEM AHMED KHAWAJA ANSAR YASIN MUHAMMAD NAWAZ TAHIR 《结构化学》2015,34(7)
A new compound 3-(2-(3,5-diphenyl-4,5-dihydropyrazol-1-yl)thiazol-4-yl)-2Hchromen-2-one was synthesized by cyclocondensation of 3,5-diphenyl-4,5-dihydropyrazole-1-carbothioamide with 3-(2-bromoacetyl)-2H-chromen-2-one in ethanol at reflux for 2hrs. The compound was characterized by IR, 1H-NMR, 13C-NMR and single-crystal X-ray diffraction analysis. The newly synthesized compound(C27H19N3O2S) crystallizes in the triclinic system, space group P1 with a = 5.2476(6), b = 18.289(2), c = 23.115(3) , α = 93.546(7), β = 94.715(6), γ = 92.347(7)°, V = 2204.3(4)3, Z = 4, Mr = 449.51, crystal size = 0.38 mm × 0.22 mm × 0.16 mm,(I 2σ(I)) = 35317, 9736, 3785, Rint = 0.081,(Δρ)max = 0.19 and(Δρ)min = –0.24 e·-3. DNA interaction studies revealed that the target compound strongly interacts with DNA through an intercalation binding mode and the binding constant of the compound is 7.45 × 104 M-1. 相似文献
15.
An efficient method has been developed for the synthesis of 2-[3(5)-aryl(methyl)pyrazol-4-yl]-1H-benzimidazoles by cyclocondensation
of 2-acylmethyl-1H-benzimidazoles benzoylhydrazones with DMF dimethylacetal. The tautomerism of the compounds obtained via
migrations of a proton between the pyrazole nitrogen atoms has been studied by 1H NMR. The more stable tautomers have electron acceptor aryl substituents placed at position 3 of the pyrazole ring and electron
donor aryl substituents or a methyl at position 5.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1370–1377, September, 2006. 相似文献
16.
On reaction with α-haloketones or hydrazine, 1-(N-arylthiocarbamoyl)amidino-3,5-dimethylpyrazoles (1) afford 2,4-diaminothiazoles and 3,5-diamino-1,2,4-triazoles in good yield. A convenient route to 1 is also reported. 相似文献
17.
P. L. Trakhtenberg M. N. Zemtsova A. N. Gusarov V. P. Zvolinskii A. E. Lipkin 《Chemistry of Heterocyclic Compounds》1979,15(6):608-611
The electronic structures and reactivity indexes (RI) of 2-(4-R-2-quinolyl)thiophenes and 5-(4-R-2-quinolyl)-2,2-dithienyls (R = H, COOH, COOC2H5, and NHCOCH3) and their protonated forms were calculated by the Pariser-Parr-Pople (PPP) method. The peculiarities of the geometrical and -electron structures were established. The calculated reactivity indexes are compared with experimental data on the electrophilic substitution reactions of the investigated compounds. A qualitative agreement between the calculated values and the experimental data was established. It is shown that quinoline derivatives of thiophene are less reactive than the corresponding dithienyl compounds in electrophilic substitution reactions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 751–754, June, 1979. 相似文献
18.
O. A. Sadygov 《Russian Journal of General Chemistry》2009,79(8):1691-1697
Induced hydroxyhalogenation of alkyl cyclohexenyl ketones in the systems [MHlg-HX or HHlg]-H2O2 or (NaClO) was performed and the optimal conditions of this reaction were elucidated. It is established that in the system
in situ is induced a hypohaloid acid HClO or HBrO is produced that then enters into electrophilic addition at the ring double
bond affording hydroxyhalo derivatives of the cycloaliphatic ketones. The alkyl cyclohexenyl ketone chloro(bromo)hydrines
and the oxiranes obtained from them are very reactive compounds and can be used as initial compounds for the synthesis of
many individual organic compounds 相似文献
19.
Pashkevich K. I. Sevenard D. V. Khomutov O. G. Vorontsov I. I. 《Russian Chemical Bulletin》2001,50(4):669-672
An efficient procedure for the synthesis of 3-cyano-4-difluoromethyl- and 3-cyano-4-trifluoromethyl-2(1H)-pyridones was developed. The structure of one of the resulting compounds was established by X-ray diffraction analysis. 相似文献
20.
V. N. Komissarov 《Chemistry of Heterocyclic Compounds》1990,26(4):414-416
Reaction of 2,6-di-tert-butyl-1,4-benzoquinone with o-phenylendiamine gives 2,6-di-tert-butyl-1,4-benzoquinone-4-(N-o-aminophenyl)imine which reacts smoothly with heterocyclic, aromatic and aliphatic aldehydes to form (1-(3,5-di-tert-butyl-4-hydroxyphenyl)-2-substituted benzimidazoles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 483–485, April, 1990. 相似文献