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1.
We have established that when 5-chloro-6-[cyano(2,3-dihydro-1-R-benzo[d]azol-2-yl)methyl]-2,3-pyrazinedicarbonitriles are reacted with nucleophilic reagents (aliphatic and aromatic amines, hydrogen sulfide), annelation of the five-membered ring occurs on the [b] face of the pyrazine with formation of 6-amino-7-hetaryl-5-R-5H-pyrrolo[2,3-b]pyrazine-2,3-dicarbonitriles and 6-amino-7-(1H-benzo[d]imidazol-2-yl)thieno[2,3-b]pyrazine-2,3-dicarbonitrile respectively. Further heating with excess of acylating reagent leads to formation of a novel heterocyclic system 1H-benzo[4,5]imidazo[1,2-c]pyrazino[2',3':4,5]pyrrolo[3,2-e]pyrimidine. Reaction of vicinal dinitriles with hydrazine hydrate leads to the novel system 1H-pyrrolo[2',3':5,6]pyrazino[2,3-d]pyridazine. 相似文献
2.
The reaction of E-2-acetyl-2,3-diphenyloxirane with ethyl trifluoroacetate in the presence of sodium isopropoxide leads to 3-hydroxy-2,3-diphenyl-6-trifluoromethyl-2,3-dihydro-4H-pyran-4-one. Under the same conditions Z-acetyloxirane forms 3-hydroxy-2-phenyl-5-trifluoromethylfuran as a result of retroaldol cleavage of the initial cyclocondensation product. 相似文献
3.
Hydrogen bonding and the electron-withdrawing or electron-donating characteristics of substituent groups that are neighboring to epoxide groups can affect the reactivity of the epoxide ring. The crystal structure ofcis-2,3-epoxycyclooctanol has been determined as a saturated eight-membered ring compound in which a hydroxyl group is attached to the C(1) atom that is adjacent to a 2,3-fused epoxy ring. The findings are that the longer epoxide C-O bond (and hence the one expected to be more readily broken) is the one farther from the hydroxyl group [1.462(1) å versus 1.447(1) å] and that the optimal hydrogen bonding is to an adjacent molecule radier than within the molecule. The shortest C-C bond is that of the epoxide group; the bond adjacent to it (on the side farther from the hydroxyl group) is the next shortest. 相似文献
4.
A. E. Shchekotikhin Y. N. Luzikov Y. B. Sinkevich V. N. Buyanov M. N. Preobrazhenskaya 《Chemistry of Heterocyclic Compounds》2008,44(10):1245-1249
On chlorination of 4,11-dimethoxynaphtho[2,3-f]indole-5,10-dione with sulfuryl chloride in chloroform, its mono-, di-, and trichloro derivatives are formed depending on
the conditions. Hydrolysis of the di- and trichloro derivatives gives a new polycondensed derivative of isatin, 4,11-dimethoxynaphtho-[2,3-f]isatin-5,10-dione. Its demethylation occurs effectively on extended heating with HBr in acetic acid and leads to 4,11-dihydroxynaphtho[2,3-f]isatin-5,10-dione (4,11-di-hydroxynaphtho[2,3-f]indole-2,3,5,10-tetraone).
*For Communication 6 see [1].
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1532–1536, October, 2008. 相似文献
5.
Yvonne Syha Charlene Valmalle Jan W. Bats Michael Kock Mona Abdel-Tawab Manfred Schubert-Zsilavecz 《Monatshefte für Chemie / Chemical Monthly》2006,137(10):1357-1364
Summary. Although various thiazoles are known in literature for their biological and pharmacological properties only a few multi-step
synthesis pathways for the preparation of thiazolo[3,2-a]pyrimidinones have been reported, which are tedious and time-consuming. An alternative synthesis pathway is described, which
allows the preparation of 2,3-dihydrothiazolo[3,2-a]pyrimidin-5-ones in a one-step process based on a Michael-type tandem reaction. By heating of 2-thiobarbituric acid with ethyl 4-bromocrotonate in ethanol at 60°C for 2 h, a 2,3-dihydrothiazolo[3,2-a]pyrimidin-5-one was obtained in 73% yield, whereas carrying out the reaction at room temperature results in the formation
of an unstable unsaturated ester. The structures of both, the α,β-unsaturated ester as well as the 2,3-dihydrothiazolo[3,2-a]pyrimidin-5-one were confirmed by NMR spectroscopy. Additionally, the structure of the 2,3-dihydrothiazolo[3,2-a]pyrimidin-5-one was investigated by single-crystal X-ray analysis. The described approach offers a significant improvement
over previously reported synthesis pathways because it allows the simple preparation of 2,3-dihydrothiazolo[3,2-a]pyrimidin-5-ones with good yields in a one-step reaction. 相似文献
6.
S. V. Tolkunov M. A. Kryuchkov V. S. Tolkunov V. I. Dulenko 《Chemistry of Heterocyclic Compounds》2004,40(8):1082-1086
We have studied the reactions of benzothieno[2,3-c]pyrylium salts with primary amines. We have shown that recyclization occurs in two directions, and whether benzothieno[2,3-c]pyridinium salts or 1-aminodibenzothiophenes are formed is determined by the nature of the primary amine. 相似文献
7.
M. M. Lipunov E. A. Kaigorodova L. D. Konyushkin S. I. Firgang G. D. Krapivin 《Chemistry of Heterocyclic Compounds》2007,43(9):1189-1196
It has been established that the interaction of N1-(2-hydroxyphenylmethylthieno[2,3-b]pyrid-3-yl)arylamides with hydrazine hydrate leads to thieno[2,3-b]pyridine-2,3-diamines.
It was shown that the reaction of the latter with acetylacetone and acetoacetic ester occurs regioselectively at the amino
group in position 3 of the thiophene ring.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1400–1408, September, 2007. 相似文献
8.
O. A. Sof''ina N. M. Igidov E. N. Koz''minykh N. N. Trapeznikova Yu. S. Kasatkina V. O. Koz''minykh 《Russian Journal of Organic Chemistry》2001,37(7):1017-1025
Acylpyruvic acids readily react with 2,3-diaminopyridine to form (Z)-3-acylmethylene-1H-3,4-di- hydropyrido[2,3-b]pyrazin-2-ones. 5-Aryl-2,3-dihydrofuran-2,3-diones which can be regarded as lactones derived from -enolized aroylpyruvic acids react with 2,3-diaminopyridine under mild conditions, yielding regioisomeric (Z)-2-aroylmethylene-4H-1,2-dihydropyrido[2,3-b]pyrazin-3-ones. The structure of the products and reaction chemoselectivity are discussed. 相似文献
9.
Z. G. Aliev S. N. Shurov V. A. Glushkov L. N. Karpova Yu. S. Andreichikov L. O. Atovmyan 《Russian Chemical Bulletin》1997,46(10):1751-1754
The reaction of 5-phenyl-2,3-dihydrofuran-2,3-dione with 6,7-dimethoxy-3,4-dihydroisoquinoline gave 1-benzoyl-2-hydroxy-8,9-dimethoxy-3,5,6,10b-tetrahydropyrrolo[2,1-a]isoquinolin-3-one and its oxidation product,viz., 1-benzoyl-8,9-dimethoxy-2,3,5,6-tetrahydropyrrolo[2,1-a]isoquinoline-2,3-dione. The last-mentioned compound was studied by X-ray structural analysis.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1845–1848, October, 1997. 相似文献
10.
S. A. Yamaskhin G. A. Romanova E. A. Oreshkina N. V. Zhukova 《Chemistry of Heterocyclic Compounds》2006,42(1):77-85
It has been shown that the condensation reaction of 5-amino-2,3-dimethyl-and 1,2,3-trimethylindoles with 4,4,4-trifluoroacetoacetic
ester occurs either via the trifluoromethylcarbonyl or the ester group depending upon the conditions under which it is carried
out. Under thermal conditions (refluxing in diphenyl) the enaminocrotonates formed are readily converted to pyrrolo[3,2-f]quinolines
and the amides cyclize in trifluoroacetic acid at 78°C to give pyrrolo[2,3-g]quinolines.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 86–96, January, 2006. 相似文献
11.
E. Suloeva M. Yure E. Gudriniece S. Belyakov M. Petrova I. Kalnite 《Chemistry of Heterocyclic Compounds》2001,37(3):329-337
Syntheses are reported for a series of 2-alkylamino-6-phenyl-4-trifluoromethylpyridines. The reaction of 3-cyano-2-(hydroxyalkylamino)-6-phenyl-4-trifluoromethylpyridines with thionyl chloride gave the corresponding 2-(chloroalkylamino)pyridines, 8-cyano-5-phenyl-7-trifluoromethyl-2,3-dihydro-imidazo[1,2-a]pyridines, and 9-cyano-6-phenyl-8-trifluoromethyl-2,3,4-trihydropyrido[1,2-a]-pyrimidines. X-ray diffraction structural analysis was used to study 8-cyano-5-phenyl-7-trifluoromethyl-2,3-dihydroimidazo[1,2-a]pyridine. 相似文献
12.
Summary Reduction of 6-azidouracils2 with hydrogen palladium or sodium dithionite afforded the corresponding 6-aminouracils5 which could also be obtained by reaction of2 with triphenylphosphanevia phosphazenes and subsequent hydrolysis (Staudinger reaction). The use of trimethylphosphite instead of phosphanes yields with2b the expected trimethoxyphosphazene3c, whereas2a reacts to the phosphonoaminopyrimidine4. The syntheses of 5-hydroxy pyrido[2,3-d]pryimidine-2,4,7-triones6, pyrido[2,3-d]pyrimidine-2,4,5-triones8, cyclopenta[e]pyrido[2,3-d]pyrimidin-2,4,5-triones7a,c, and tetrahydro-pyrimido[4,5-b]quinolin-2,4,5-triones7b,d by condensation of 6-aminouracils5 with malonates, ethylaceto/benzoylacetate, ethyl 2-oxocyclopentanecarboxylate and ethyl 2-oxocyclohexanecarboxylate, respectively, are described.
Pyrido[2,3-d]pyrimidine, 2. Mitt. Einstufige Synthese von Pyrido[2,3-d]pyrimidinen und Pyrimido[4,5-b]chinolinen aus 6-Aminouracilen
Zusammenfassung Reduktion der 6-Azidouracile2 mit Wasserstoff/Palladium oder Natriumdithionit ergibt die entsprechenden 6-Aminouracile5, die auch durch Reaktion von2 mit Triphenylphosphin und anschließende Hydrolyse erhalten werden können (Staudinger-Reaktion). Die Verwendung von Trimethylphosphit anstelle von von Trimethylphosphin ergibt mit2b das erwartete Trimethoxyphosphazin3c, während2a zum Phosphonoaminopyrimidin4 reagiert. Die Synthesen der 5-Hydroxy-pyrido[2,3-d]pyrimidin-2,4,7-trione6, der Pyrido[2,3-d]pyrimidin-2,4,5-trione8, der Cyclopenta[e]pyrido[2,3-d]pyrimidin-2,4,5-trione7a,c und der Tetrahydro-pyrimido[4,5-b]chinolin-2,4,5-trione7b,d durch Kondensation der 6-Aminouracile5 mit Malonat, Acetat, Ethyl-2-oxocyclopentancarboxylat und Ethylcyclohexancarboxylat werden beschrieben.相似文献
13.
Karl Gewald Harry Schäfer Klaus Sattler 《Monatshefte für Chemie / Chemical Monthly》1979,110(5):1189-1196
The Cyclization of 2-(1,1-dicyanovinylamino)-thiophenes2 by treatment with AlCl3 yield 4-amino-5-cyano-thieno[2,3-b]pyridines3. 2-(1-acylvinyl-amino)-3-cyano-thiophenes7, obtainable from 2-amino-3-cyano-thiophenes and -diketones, react in the presence of AlCl3 to form 4-acylamino-thieno[2,3-b] pyridines8. This reaction is connected with the transfer of the acyl group from C- to the N-atom. 4-Amino-5-cyano-thieno[2,3-b]pyridones-(6)11 are synthesized from 2-amino-3-cyano-thiophenes and ethyl cyano acetate in the presence of sodium ethoxide. 相似文献
14.
V. Bobošík A. Krutošíková U. Jordis 《Monatshefte für Chemie / Chemical Monthly》1995,126(6-7):747-752
Summary A number of substituted 2,3-dimethylfuro[3,2-c]pyridines was synthesized. 3-(4,5-Dimethyl-2-furyl)propenoic acid (1) was converted to the acid azide2, which in turn was cyclized to give 2,3-dimethyl-5H-furo[3,2-c]pyridine-4-one (3) by heating at 240°C in Dowtherm. The pyridone3 was chlorinated with phosphorus oxychloride to give4, which was reduced with zinc and acetic acid to 2,3-dimethylfuro[3,2-c]pyridine (5). Treatment of4 with several secondary heterocyclic amines led to compounds6a–6c. Reaction of pyridone3 with phosphorus pentasulfide rendered the thione7, which was methylated to8a. The 4-methoxy derivative8b was obtained from4 with sodium methoxide. 2,3,5-Trimethylfuro[3,2-c]pyridine-4-one (9) was obtained by reaction of3 with methyl iodide.Dedicated to Professor Dr.Fritz Sauter on the occasion of his 65th birthday 相似文献
15.
E. A. Kaigorodova A. A. Osipova L. D. Konyushkin G. D. Krapivin 《Russian Chemical Bulletin》2004,53(4):853-859
Reactions of 2,5-dimethoxytetrahydrofuran with 3-aminothieno[2,3-b]pyridines afford a number of substituted 3-(1H-pyrrol-1-yl)thieno[2,3-b]pyridines. The possibility of the reaction and the yield of the product are determined by the character of a substituent in position 2 of thieno[2,3-b]pyridine. The Curtius rearrangement of 2-acylazido-3(1H-pyrrol-1-yl)thieno[2,3-b]pyridines yields 4,5-dihydropyrido[3",2":4,5]thieno[2,3-e]pyrrolo[1,2-a]pyrazin-4-ones. The molecular and crystal structures of ethyl 4-methoxymethyl-6-methyl-3-(1H-pyrrol-1-yl)thieno[2,3-b]pyridine-2-carboxylate were determined by X-ray diffraction analysis. 相似文献
16.
E. N. Kozminykh N. M. Igidov G. A. Shavkunova V. O. Kozminykh 《Russian Chemical Bulletin》1997,46(7):1285-1290
2-p-Chlorobenzoylmethylene-5-phenyl-2,3-dihydro-3-furanone reacts with arylamines orN-arylideneamines to form the products of ring opening, 1,6-diaryl-1-arylamino-4-hydroxy-1,4-hexadiene-3,6-diones. The reaction
of 5-aryl-2-p-chlorobenzoylmethylene-2,3-dihydro-3-furanones witho-aminophenol afforded 3-p-chlorobenzoylmethylene-3,4-dihydro-2H-benzo[b]-1,4-oxazin-2-one. Nucleophilic attack of amines is directed either to electrophilic centers at the C(5) and C(2) atoms or
to the carbonyl group of the 2-phenacylidene substituent of the 3-oxofuran ring.
For communication 15, see Ref. 1.
Translated fromIzestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1340–1345, July, 1997. 相似文献
17.
L. M. Potikha V. M. Kisil A. V. Turov V. A. Kovtunenko 《Chemistry of Heterocyclic Compounds》2008,44(3):330-338
5-Aryl-7,12-dihydroisoquino[2,3-a]quinazolinium perchlorates are readily oxidized by atmospheric oxygen to form the products
of oxidative coupling 5,5′-bis(aryl)-3,3′-dihalo[7,7′]bi[isoquino-[2,3-a]quinazoline-13,13′-diylium perchlorates. Heating
3-chloro-5-phenyl-7,12-dihydroisoquino-[2,3-a]quinazolinium perchlorate in nitrobenzene gives the 3-chloro-5-phenylisoquino[2,3-a]quinazolin-13-ium
perchlorate. The aromatic 5-arylisoquino[2,3-a]quinazoline derivatives obtained react with nucleophilic reagents to form addition
products at the C-12 atom.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 428–439, March, 2008. 相似文献
18.
I. V. Krylova D. D. Nekrasov Yu. S. Andreichikov 《Chemistry of Heterocyclic Compounds》1988,24(11):1204-1206
The reaction of 5-aryl-2,3-dihydrofuran-2,3-diones with benzamide oxime, diaminoglyoxime, and hydroxyurea gave 3-phenyl-5-aroylacetyl-1,2,4-oxadiazoles, 5,6-dihydroxyimino-3-phenacylidenepiperazin-2-ones, and 3-hydroxy-5-phenacylideneimidazolidine-2,4-diones, respectively. 6-Phenacylidene-5-oxo-4,5,6,7-tetrahydrofurazano [3,4-b]pyrazines are formed in the reaction of 5-aryl-2,3-dihydrofuran-2,3-diones with diaminofurazan.For Communication 7, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1457–1460, November, 1988. 相似文献
19.
J. Suloeva M. Jure E. Gudriniece M. Petrova A. Kemme 《Chemistry of Heterocyclic Compounds》2002,38(6):714-729
The alkylation, acylation, halogenation, nitration, oxidation, and hydrolysis reactions of 8-cyano-5-phenyl-7-trifluoromethyl-2,3-dihydroimidazo[1,2-a]pyridine have been studied. It was found that the 6-halo derivatives add alcohol to give covalent solvates. X-ray analysis has been carried out on one of the solvates (6-chloro-8-cyano-7-ethoxy-5-phenyl-7-trifluoromethyl-1,2,3,7-tetrahydroimidazo[1,2-a]pyridine) as well as on 8-cyano-5-phenyl-7-trifluoromethyl-2,3-dihydroimidazo[1,2-a]pyridine trifluoroacetate. 相似文献
20.
The acylation of benzo[b]furan-, benzo[b]thiophene, and indolyl-3-acetic acid arylamides using acetic anhydride in the presence of 70% perchloric acid occurs at the -position of the heterocycle to give 2-acetylbenzo[b]furan-, 2-acetylbenzo[b]thiophene, and 2-acetylindolyl-3-acetic acid arylamides. Depending on the amount of perchloric used in the reaction they undergo cyclodehydration to 3-arylamino-1-methylhetero[2,3-c]pyrilium salts and to N-aryl-1-methyl-3(2H)hetero[2,3-c]pyridones. 相似文献