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1.
《Journal of heterocyclic chemistry》2017,54(5):2614-2626
2‐Cyano‐N‐(antipyrin‐4‐yl)‐3‐(ethylthio)‐3‐(naphthalen‐1‐ylamino)acryl‐amide 4 was achieved via a one‐pot, three‐component reactions of cyanoacetamide derivative 2 , 2‐naphthyl isothiocyanate, and diethyl‐sulphate. The cyano acrylamide derivative 4 was hydrazinolysis to furnish 5‐aminopyrazole 5 ; many pyrazolo[1,5‐a ]pyrimidines 10a,b, 14, 15, 16, 18, and 20 have been synthesized via treatment of 5 with some electrophilic reagents. Also, ternary condensation of cyanoacetamide derivative 2 , terephthalaldehyde, and active methylene derivatives afforded bispyridone derivatives 21a,b . The structures of the new compounds were confirmed on the basis of elemental analysis and spectral data. Representative compounds of the synthesized products were tested and evaluated as antimicrobial. In general, the novel‐synthesized compounds showed a good antimicrobial activity against Gram‐positive bacteria, Gram‐negative bacteria, and antifungal activity against Azithromycin and Ketoconazole . The molecular modeling of the 21a and 21b as representative examples of the synthesized compounds has been drawn, and their molecular parameters were calculated. 相似文献
2.
Madhukar N. Jachak Appasaheb B. Avhale Chanda D. Tantak Raghunath B. Toche Claudia Reidlinger Wolfgang Stadlbauer 《Journal of heterocyclic chemistry》2005,42(7):1311-1319
A series of 1,3,6‐trisubstituted and 1,3,5,6‐tetrasubstituted pyrazolo[3,4‐b]pyridines 5 has been synthesized by Friedlander condensation of 5‐arninopyrazole‐4‐carbaldehydes 3 with α‐methylene ketones such as acetone (4a) or acetophenones 4b‐f with potassium hydroxide as basic catalyst. Condensation of 5‐aminopyrazole‐4‐carbaldehydes 3 and unsymmetric dialkylketones 6 yielded mixtures of isomeric pyra‐zolo[3,4‐b]pyridine derivatives 7 and 8 . Condensation of 5‐aminopyrazole‐4‐carbaldehydes 3 with CH‐acidic acylacetonitriles 9 and acylacetates 11 with piperidine as basic catalyst yielded pyrazolo[3,4‐b]pyri‐dine‐5‐carbonitriles 10 and pyrazolo[3,4‐b]pyridine‐5‐carboxylates 12 ; with diethyl malonate 13 as CH‐acidic component, pyrazolo[3,4‐b]pyridin‐6‐ones 14 were obtained. 相似文献
3.
Khaled S. Mohammed Engy E. Elbeily Fathy M. El‐Taweel Ahmed A. Fadda 《Journal of heterocyclic chemistry》2019,56(2):493-500
5‐Hydrazineyl‐3‐methyl‐1H‐pyrazole ( 1 ) was used as a starting material for the synthesis of novel pyrazolo[3,4‐c][1,2]diazepine derivatives 3 , 4 , and 6a,b by its reaction with acetylacetone, ethyl acetoacetate, and isatylidene derivatives 5a,b , respectively. Also, pyrazolo[3,4‐c][1,2]diazepine derivative 11 was synthesized via multicomponent reaction of 1 , benzaldehyde, and malononitrile. Moreover, compound 1 was used for synthesis novel pyrazolo[3,4‐c]pyrazole derivative 7 by its reaction with isatin. In addition, pyrazolo[3,4‐c]pyrazole derivatives 18a–c were synthesized by treatment of 2‐cyano‐N′‐(3‐methyl‐1H‐pyrazol‐5‐yl)acetohydrazide ( 13 ) with aromatic aldehydes 16a–c . The newly synthesized compounds were valeted by means of analytical and spectral data. All newly synthesized compounds were screened for their antioxidant activities. Compounds 3 , 13 , 18b , and 18c showed higher radical‐scavenging activities. 相似文献
4.
Saleh M. Al‐Mousawi Mohammad A. Mohammad Mohamad H. Elnagdi 《Journal of heterocyclic chemistry》2001,38(4):989-991
While 3(5)‐aminopyrazole reacts with enaminonitrile to yield pyrazolo[1,5‐a]pyrimidines, 3‐amino‐5‐pyrazolone reacts with the same reagents to yields pyrazolo[3,4‐b]pyridines. 相似文献
5.
Mahmoud A. Mohamed 《Journal of heterocyclic chemistry》2012,49(1):200-203
Cyclocondensation of cyanoacetamide and cyanothioacetamide with sodium salt of 3‐hydroxy‐1‐(pyridin‐3‐yl)prop‐2‐en‐1‐one gave 6‐oxo‐[2,3′]bipyridine 5a and 6‐thioxo‐[2,3′]bipyridine 5b derivatives, respectively. Compound 5b upon treatment with different methylenes 8 gave thieno[2,3‐b]pyridines 10 . Treatment of 5b with iodomethane gave bipyridine derivative 7 , which cyclocondensed with hydrazines 11 to give pyrazolo[3,4‐b]pyridines 13 . J. Heterocyclic Chem., (2012). 相似文献
6.
Wafaa S. Hamama Hamada G. El‐Gohary Mamdouh Soliman Hanfi H. Zoorob 《Journal of heterocyclic chemistry》2012,49(3):543-554
This research work describes the synthesis and biological properties of some novel isolated or fused heterocyclic ring systems with pyrazole, for example; enaminones containing pyrazolone ring photochromic functional unit, 4‐[(4‐chlorophenylamino)methylene]‐3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐one (3) and some analogous derivatives 4, 9, and 10, also as pyrazolo[3,4‐b]pyridine, pyrazolo[3,4‐b]quinoline, pyrazolo[3′,4′:4,5]thieno[2,3‐c]pyrazoline and pyrazolo[3,4‐c]pyrazole were synthesized and characterized. Newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR, mass spectral data and quantum mechanical calculations. Selected products were tested for their antibacterial and antitumor agents. 相似文献
7.
Synthesis of the title compounds was achieved using the anils 2a , 2b , 2c , 2d , 2e and 5a , 5b , 5c derived from the 4‐aminopyrazole 1 as starting materials. These compounds were allowed to react with mercaptoacetic acid in boiling dry benzene to afford the corresponding thiazolidinones and spiro‐thiazolidinones 3a , 3b , 3c , 3d , 3e and 6a , 6b , 6c , respectively. Pictet—Spengler reaction of the 4‐aminopyrazole hydrochloride 7 with aromatic aldehydes and cyclic ketones resulted in the formation of new pyrazolo[4,3‐e]pyrrolo[1,2‐a]pyrazines 8a , 8b , 8c , 8d , 8e and 9a , 9b , respectively. Other derivatives of pyrazolo pyrrolopyrazines 10 and 11 were obtained via the reaction of the amino derivative 1 with 1,1′‐carbonyldiimidazol and CS2, respectively. J. Heterocyclic Chem., (2011). 相似文献
8.
A series of pyrazolo[3,4‐b]pyridines was synthesized by the reaction of 5‐aminopyrazole with benzylidenemalononitrile in aqueous media. The structures were characterized by IR, 1H NMR, and elemental analysis and were further confirmed by X‐ray diffraction analysis. 相似文献
9.
Ahmet ener M. Kasim ener Ishak Bildmci Rahmi Kasimogullari Yunus Akamur 《Journal of heterocyclic chemistry》2002,39(5):869-875
The 1H‐pyrazole‐3‐carboxylic acid 2 , obtained from the furan‐2,3‐dione 1 and N‐Benzylidene‐N'‐(3‐nitrophenyl) hydrazine, was converted via reactions of its acid chloride 3 with various alcohols or N‐nucleo‐philes into the corresponding ester or amide derivatives 4 or 5 , respectively. Nitrile 6 and anilino‐pyrazole acid 7 derivatives of 2 were also obtained by dehydration of 5a in a mixture of SOCl2 with DMF and reduction of 2 with sodium polysulphide, respectively. While cyclocondensation reactions of 2 or 7 with phenyl hydrazine or hydrazine hydrate and 6 with only anhydrous hydrazine lead to derivatives of pyrazolo[3,4‐d]‐pyridazinone 8 and pyrazolo[3,4‐d]pyridazine amine 9 , respectivel. The reaction of 2 with 2‐hydrazinopyri‐dine provided hydrazono‐pyrazole acid derivative 10 , which was decarboxylated to give hydrazono‐pyra‐zole derivative 11 . Pyrazolo[4,3‐d]oxazinone 12 and 2‐quinolyl pyrazolo[3,4‐d]pyridazine 13 derivatives were also prepared by cyclocondensation reactions of 2 with hydroxylamine hydrochloride and 7 with acetaldehyde, respectively. 相似文献
10.
Pyrrolo[3,4‐c]pyrazole‐4,6‐diones, pyrazoles, pyrazolo[3,4‐d]pyridazines, and pyrazolo[3,4‐d]pyrimidines were prepared via 1‐bromo‐2‐(5‐chlorobenzofuran‐2‐yl)ethanedione‐1‐phenylhydrazone with N‐arylmalemides and active methylene. All newly synthesized compounds were confirmed by elemental analysis and spectral data. 相似文献
11.
Talaat Ibrahim El‐Emary 《中国化学会会志》2006,53(2):391-401
New derivatives of pyrazolo[3,4‐b]pyrazine and related heterocycles were prepared starting from 6‐amino‐3‐methyl‐1‐phenyl‐1H‐pyrazolo[3,4‐b]pyrazine‐5‐carbonitrile ( 2 ) and using the key intermediates 4 , 5 , 6 , 14 , 15 and 16 . Some of the prepared compounds were evaluated for their antifungal and antibacterial activities. 相似文献
12.
Microwave‐Assisted Three‐Component Reactions Leading to Pyrano‐Fused Pyrazolo[3,4‐b]pyridines
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Bi‐Hui Xu Man‐Su Tu Yin‐Ping Liu Bo Jiang Xing‐Hang Wang Shu‐Jiang Tu 《Journal of heterocyclic chemistry》2014,51(6):1591-1594
A series of pyrano‐fused pyrazolo[3,4‐b]pyridine derivatives with an aryl group presenting the 2‐position of the pyridine nucleus have been synthesized by microwave‐assisted three‐component reactions of aldehydes, tetrahydropyran‐4‐one, and 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5‐amine in HOAc. This method is very efficient because of short reaction times and easy work‐up, and it provides an efficient and promising synthetic strategy for the construction of the tricyclic pyrano‐fused pyrazolo[3,4‐b]pyridine skeleton. 相似文献
13.
《Journal of heterocyclic chemistry》2018,55(1):161-165
Several derivatives of the new pyrimido[4′,5′:3,4]pyrazolo[1,2‐b]phthalazine‐4,7,12‐trione ring system have been prepared by the reaction of 3‐amino‐1‐aryl‐5,10‐dioxo‐5,10‐dihydro‐1H‐pyrazolo[1,2‐b]phthalazine‐2‐carbonitriles with aliphatic carboxylic acids in the presence of phosphoryl chloride (POCl3). The synthesized compounds were characterized on the basis of IR, 1H NMR, and 13C NMR spectral and microanalytical data. 相似文献
14.
Anton V. Dolzhenko Shiqi Bai Anna V. Dolzhenko Wai Keung Chui 《Journal of heterocyclic chemistry》2012,49(4):763-767
A new convenient synthon for heterocyclic chemistry, namely 1H‐pyrazolo[3,4‐b]pyridin‐3‐ylguanidine was successfully prepared by selective guanylation of 1H‐pyrazolo[3,4‐b]pyridin‐3‐amine. A series of 3,4‐dihydropyrido[2′,3′:3,4]pyrazolo[1,5‐a][1,3,5]triazin‐2‐amines was synthesized from 1H‐pyrazolo[3,4‐b]pyridin‐3‐ylguanidine using aldehydes or ketones as one‐carbon inserting reagents. The tautomeric preferences of the products were determined using spectroscopic (e.g., 2D NOESY NMR) and single crystal X‐ray diffraction data. 相似文献
15.
Facile Route to Novel Pyrazolo[3,4‐d]pyrimidine,Imidazo[1,2‐b] pyrazole,Pyrazolo[3,4‐d][1,2,3]triazine,Pyrazolo[1,5‐c][1,3,5]triazine and Pyrazolo[1,5‐c][1,3,5]thiadiazine Derivatives
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Samir Bondock Abd El‐Gaber Tarhoni Ahmed A. Fadda 《Journal of heterocyclic chemistry》2015,52(2):346-351
A regioselective synthesis of novel pyrazolo[3,4‐d]pyrimidines, imidazo[1,2‐b]pyrazoles, pyrazolo[3,4‐d][1,2,3]triazine, pyrazolo[1,5‐c][1,3,5]triazine and pyrazolo[1,5‐c][1,3,5]thiadiazine incorporating a thiazole moiety was described via the reactions of the versatile, readily accessible 5‐amino‐3‐(phenylamino)‐N‐(4‐phenylthiazol‐2‐yl)‐1H‐pyrazole‐4‐carboxamide ( 1 ) with each of DMF‐DMA, phenylisothiocyanate, chloroacetyl chloride, phenacyl bromide, benzoylisothiocyanate and formalin, respectively. All structures of the newly synthesized compounds were elucidated by elemental analysis and spectral data. 相似文献
16.
Sherif M. H. Sanad Azza M. Abdel‐Fattah Fawzy A. Attaby Mohamed A. A. Elneairy 《Journal of heterocyclic chemistry》2019,56(2):651-662
Pyridine‐2(1H)‐thiones were prepared and reacted with several active halogenated reagents to afford novel thieno[2,3‐b]pyridines in excellent yields. Thieno[2,3‐b]pyridine‐2‐carbohydrazide derivative was prepared by the reaction of either ethyl 2‐((3‐cyanopyridin‐2‐yl)thio)acetate derivative or thieno[2,3‐b]pyridine‐2‐carboxylate derivative with hydrazine hydrate. On the other hand, the reaction of either pyridine‐2(1H)‐thione or ethyl 2‐((pyridin‐2‐yl)thio)acetate derivative with hydrazine hydrate afforded the corresponding 1H‐pyrazolo[3,4‐b]pyridine derivative. Thieno[2,3‐b]pyridine derivatives reacted with several reagents to afford the corresponding pyrimidine‐4(3H)‐ones and [1,2,3]triazin‐4‐(3H)‐one. Moreover, 2‐carbohydrazide derivative reacted with β‐dicarbonyl reagents to give 2‐((3‐methyl‐1H‐pyrazol‐1‐yl)carbonyl)thienopyridines. The structure of the target molecules is elucidated using elemental analyses and spectral data. 相似文献
17.
An unexpected multicomponent reaction of cyanothioacetamide with aromatic aldehydes and aminopyrazole under MWI was found and reported. It turned out to be an efficient and simple procedure for the preparation of pyrazolo[3,4‐b]pyridine derivatives. The structure of the product was characterized by IR, MS, 1H and 13C NMR, COSY and NOESY spectroscopy, X‐ray crystallographic analysis, and by comparison with the authentic sample prepared with the known procedure. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:694–699, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20497 相似文献
18.
A.Y. Hassan N.M. Saleh Mona. S. Kadh E.S. Abou-Amra 《Journal of heterocyclic chemistry》2020,57(7):2704-2721
Novel pyrazolopyrimidines and their fused derivatives derived from aminopyrazole moiety as pyrazoloquinazoline, chromenopyrazolopyrimidine, pyrazolopyrimidopyrimidine, pyrazolopyrimidotriazepine and benzoimidazopyrazolopyrimidine were designed, synthesized and evaluated for their anticancer activities. Twenty of the synthesized compounds were tested by the National Cancer Institute (NCI, Bethesda, USA) at a single high dose (10-5 M). It was found that 5-amino-1H-pyrazole-4-carbonitrile derivative, pyrazolo[5,1-b]quinazoline-11-carbonitrile derivative and 1-amino-2,4-dihydro-5H-benzo[4,5]imidazo[1,2-c]pyrazolo[4,3-e]pyrimidin-5-one were own widely selective powerful anticancer activity towards certain cancer cell lines and this also proved through docking studies with cyclooxygenase-2 (COX-2) enzyme. 相似文献
19.
Selective Synthesis of New Tetracyclic Coumarin‐fused Pyrazolo[3,4‐b]pyridines and Pyrazolo[3,4‐b]pyridin‐6(7H)‐ones
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A three‐component reaction for the synthesis of new coumarin‐fused tetracyclic system from 4‐hydroxycoumarin, aldehydes, and 5‐aminopyrazoles/5‐aminoisoxazole is described. In the presence of acetic acid, 4,7‐dihydro‐1H‐pyrazolo[3,4‐b]pyridines ( 4 ) and pyrazolo[3,4‐b]pyridines ( 5 ) were obtained in acetonitrile and dimethylsulfoxide medium, respectively. The reaction gave rise to 4,5‐dihydro‐1H‐pyrazolo[3,4‐b]pyridin‐6(7H)‐ones ( 6 ) in acetic acid–ethanol combination system, which involved the C–O bond cleavage. 4‐Hydroxy‐6‐methyl‐2H‐pyran‐2‐one and acenaphthylene‐1,2‐dione were also examined, affording the corresponding C–O bond cleavage products. Mechanism indicates that the reaction is reversible in acetic acid–ethanol combination system. 相似文献
20.
《Journal of heterocyclic chemistry》2018,55(2):545-550
A novel imidazo[4′,5′:3,4]pyrazolo[5,1‐c][1,2,4]triazine‐4,8‐dione heterocyclic system was synthesized starting from available 4‐amino‐6‐tert‐butyl‐3‐methylthio‐1,2,4‐triazin‐5(4H)‐one in four steps with 28% overall yield. 相似文献