共查询到20条相似文献,搜索用时 15 毫秒
1.
N. G. Korzhenevskaya E. V. Titov Yu. M. Yutilov R. M. Bystrova 《Chemistry of Heterocyclic Compounds》1975,11(1):78-80
It was shown by means of UV and IR spectroscopy and the ionization constants that the tautomeric equilibrium of 2-amino- and 2-mercapto derivatives of 3-methyl-3H-imidazo[4,5-b]pyridine is shifted to favor the amino and thione forms, respectively. 相似文献
2.
Lothar Hennig Mario Alva-Astudillo Reinhard Meusinger Gerhard Mann 《Monatshefte für Chemie / Chemical Monthly》1993,124(8-9):893-898
Summary Donor substituted arylidene aminopyrazoles1a–c and CH-acidic 1,3-dicarbonyl compounds2a–e give in ethanol in an addition/cyclization reaction pyrazolo[3,4-c]isoquinolines4a–i and pyrazolo[3,4-b]pyridine derivatives5a,b, respectively. Using ethyl cyanoacetate as CH-acidic component, cinnamate6 and the cyano substituted pyrazolo[3,4-b]pyridine7 are formed.
Synthese von Pyrazolo[3,4-c]isochinolin- und Pyrazolo[3,4-b]pyridin-Derivaten aus Azomethinen und CH-aciden Verbindungen
Zusammenfassung Die Reaktion der donorsubstituierten Aryliden-aminopyrazole1a–c mit den CH-aciden 1,3-Dicarbonylverbindungen2a–e führt in einer Additions/Cyclisierungsreaktion zu den Pyrazolo[3,4-c]isochinolin-4a–i bzw. Pyrazolo[3,4-b]pyridin-Derivaten5a,b. Verwendet man Cyanessigester als CH-acide Komponente, werden der Zimtsäureester6 und das cyanosubstituierte Pyrazolo[3,4-b]pyridin7 gebildet.相似文献
3.
L. Bukowski Z. Zwolska E. Augustynowicz-Kopec 《Chemistry of Heterocyclic Compounds》2006,42(10):1358-1365
The reactions of 2-acetylimidazo[4,5-b]pyridine hydrazone with some alkyl-and arylisothiocyanates and some orthoesters were
carried out. Various new derivatives of the titled compound such as thiosemicarbazones, ethoxymethylenehydrazones, and derivatives
of the new pyrido-[3′,2′:4,5]imidazo[1,2-d][1,2,4]triazine ring system were obtained. Biological data for selected compounds
are presented.
Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1571–1579, October, 2006. 相似文献
4.
A simple and novel protocol for the efficient synthesis of a series of 8-carboxylnaphthyl functionalized pyrazolo[3,4-b]pyridine derivatives was developed through a one-pot, three-component reaction involving acenaphthylene-1,2-dione and 1H-pyrazol-5-amine in acetic acid medium. The reaction represents the first facile conversion of acenaphthenequinone to naphthoic acid via C-C bond cleavage without need for multi-step transformation. 相似文献
5.
Alcione S. De Carvalho Carlos A. M. Fraga Eliezer J. Barreiro 《Journal of heterocyclic chemistry》1996,33(2):309-313
In this paper we report the synthesis of an isosteric series of new heterotricyclic derivatives, corresponding to pyrazolo[3,4-b]thieno[2,3-d]pyridine ( 1 ), pyrazolo[3,4-b]furano[2,3-d]pyridine ( 2 ) and pyrazolo[3,4-b]pyrrolo[2,3-d]pyridine ( 3 ). These functionalized compounds were obtained, in high overall yield, by an ‘one-pot’ reaction of the chloroester intermediate 4 , possessing the pyrazolo[3,4-b]pyridine system, with an adequate α-hetero-acetyl ester derivative, in SNAr/Dieckman cyclization type consecutive reactions. 相似文献
6.
L. Bukowski 《Chemistry of Heterocyclic Compounds》2002,38(7):828-835
New imidazo[4,5-b]pyridine derivatives with various substituents in the 2-position (,-unsaturated ketones, imines, 2-pyrazolines, pyrimidines, 1,2,3,4-tetrahydropyrimidines) and derivatives of the new pyrido[3',2':4,5]imidazo[1,2-d][1,2,4]triazine ring system were synthesized. Biological data for selected compounds are presented. 相似文献
7.
1,2,3-Triazolo[4,5-b]pyridines and pyrazolo[4,3-b]pyridines can be readily prepared via cyanoacetylation reactions of 5-amino-1,2,3-triazoles 1a,b and 4-amino- pyrazole 2 followed by subsequent cyclization of the formed cyanoacetamides. Reactions of amines 1a,b with a mixture of p-nitrophenylacetic acid and acetic anhydride under microwave irradiation conditions afforded the corresponding amides 15a,b that underwent cyclization to form 1,2,3-triazolo[4,5-b]pyridines 16a,b upon heating in DMF solutions containing sodium acetate. Reactions of 1a,b with active methylene compounds, including 17a-c, in the presence of zeolites as catalyst also afforded 1,2,3-triazolo[4,5-b]pyridine derivatives 20a-f via the intermediacy of triazole derivatives 19 and not 18. 相似文献
8.
E. S. Komarova V. A. Makarov L. M. Alekseeva G. V. Avramenko V. G. Granik 《Russian Chemical Bulletin》2006,55(4):735-740
1-[4-Aminoarylpyrazolo[3,4-b]pyridin-5-yl]pyridinium chlorides undergo cyclization under reflux in tert-butanol in the presence of an excess of potassium tert-butoxide to form tetracyclic derivatives of pyrazolo[3,4-b]pyrido[1′,2′:1,2]imidazo[4,5-d]pyridine. The reaction scheme of the processes is proposed. The structures of the reaction products were confirmed by physicochemical
methods.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 710–714, April, 2006. 相似文献
9.
Sampath Ravula Ramana Reddy Bobbala Balakrishna Kolli 《Journal of heterocyclic chemistry》2020,57(6):2535-2538
A series of novel isoxazole functionalized pyrazolo[3,4-b]pyridine derivatives 5a-n were prepared, respectively, initiated from 6-thiophenyl-4-(trifluoromethyl)-1H-pyrazolo[3,4-b]pyridin-3-amine 3 through selective N-propargylation, and these N-propargylated compounds 4 were cyclized with aryloximes by using of sodium hypochlorite, and obtained the title products 5a-n . All the final products 5a-n were submitted for anticancer activity against four cancer cell lines such as “HeLa—cervical cancer (CCL-2); COLO 205—colon cancer (CCL-222); HepG2—liver cancer (HB-8065); MCF7—breast cancer (HTB-22)”; Compounds 5c , 5d , and 5h are found to have more prominent anticancer activity at micro molar concentration. 相似文献
10.
Chemistry of Heterocyclic Compounds - 相似文献
11.
It is shown that quaternization of isomers of 1-methylimidazo[4,5-b]pyridine and 3-methyl-imidazo[4,5-b]pyridine proceeds at different reaction centers — at the nitrogen atom of the imidazole ring in the first case and at the nitrogen atom of the pyridine ring in the second case.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1686–1688, December, 1973. 相似文献
12.
Unsubstituted imidazo[4,5-b]pyridine adds methyl iodide to the pyridine N atom. Treatment of the resulting iodide with base forms 4-methyl-4H-imidazo[4,5-b]pyridine. This nucleophile can readily add methyl iodide to form only one salt, 1,4-dimethylimidazo[4,5-b]pyridinium iodide.L. M. Litvinenko Institute of Physical Organic Chemistry and Coal Chemistry, Ukraine Academy of Sciences, Donetsk 340114. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1232–1233, September, 1994. Original article submitted june 17, 1994. 相似文献
13.
Fabrizio Melani Lucia Cecchi Giovanna Palazzino Guido Filacchioni 《Journal of heterocyclic chemistry》1986,23(1):173-176
Following our reports on synthetic tricyclic analogues of antitumor anthramycin the synthesis of some isomers pyrazolo[4,5-d]- and pyrazolo[4,5-c][1]benzazepine derivatives is reported. 相似文献
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15.
T. G. Koksharova V. N. Konyukhov Z. V. Pushkareva T. A. Pryakhina 《Chemistry of Heterocyclic Compounds》1972,8(2):247-251
Several derivatives of the little-studied pyridazino[4,5-b]quinoxaline heterocyclic system, the structural isomer of benzopteridine, were synthesized in order to study their biological activity. 6,7-Dimethylquinoxaline-2,3-dicarboxylic acid and a number of its derivatives were also obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 274–278, February, 1972. 相似文献
16.
17.
Two potential mutagens found in food, 1,5,6-trimethyl-2-aminoimidazo[4,5-b]pyridine and 3,5,6-trimethyl-2-aminoimidazo[4,5-b]pyridine, are synthesized. 相似文献
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20.
Augusto Colombo Jordi Frigola Juan Parés Blas Andaluz 《Journal of heterocyclic chemistry》1989,26(4):949-955
The synthesis and structure elucidation of new pyrazolo[3,4-b][1,4]diazepines and pyrazolo[3,4-b]pyrazines are reported and the characterisation of isomers and tautomers by proton and carbon-13 nmr are discussed. In some case only NOE experiments allow us to identify the isomeric structure. 相似文献