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1.
Giuliana Biagi Fabio Ciambrone Irene Giorgi Oreste Livi Valerio Scartoni Pier Luigi Barili 《Journal of heterocyclic chemistry》2002,39(5):889-893
New tricyclic 1,2,3‐triazolo‐1,2,4‐triazolo‐pyridazine derivatives, bearing a methyl substituent on the 1,2,3‐triazole ring, were prepared as potential biological agents. N‐Methylation of dimethyl 1,2,3‐triazole‐4,5‐dicarboxylate allowed synthesis of the isomeric 1‐methyl‐4,7‐dihydroxy and 2‐methyl‐4,7‐dihydroxy triazolo‐pyridazines 4a and 4b which, by a chlorination reaction, gave the corresponding 1‐methyl‐4‐chloro‐( 6a ), 1‐methyl‐7‐chloro‐ ( 6b ) and 2‐methyl‐4‐chloro‐ ( 9 ) substituted 1,2,3‐triazolo‐pyridazines. The nucle‐ophilic substitution with hydrazine hydrate and the suitable cyclization to form the 1,2,4‐triazole ring, provided the expected tricyclic isomeric derivatives 8a, 8b and 11 respectively. The p‐methoxybenzyl substituent, introduced as a leaving group to obtain either v‐triazolo‐pyridazine or v‐triazolo‐s‐triazolo‐pyri‐dazine derivatives unsubstituted on the 1,2,3‐triazole ring, appeared inadequate. Some compounds underwent binding assays toward the adenosine A1and A2A receptors. 相似文献
2.
Ho Sik Kim Geuk Jeong Hyoung Choul Lee Jin Hee Kim Yong Tae Park Yoshihisa Okamoto Shinnosuke Kajiwara Yoshihisa Kurasawa 《Journal of heterocyclic chemistry》2000,37(5):1277-1280
The reaction of the quinoxaline N‐oxide 1 with thiophene‐2‐carbaldehyde gave 6‐chloro‐2‐[1‐methyl‐2‐(2‐thienylmethylene)hydrazino]quinoxaline 4‐oxide 5 , whose reaction with 2‐chloroacrylonitrile afforded 8‐chloro‐2,3‐dihydro‐4‐hydroxy‐1‐methyl‐3‐(2‐thienyl)‐1H‐1,2‐diazepino[3,4‐b]quinoxaline‐5‐carbonitrile 6 . The reaction of compound 6 with various alcohols in the presence of a base effected alcoholysis to provide the 5‐alkoxy‐8‐chloro‐2,3,4,6‐tetrahydro‐1‐methyl‐4‐oxo‐3‐(2‐thienyl)‐1H‐1,2‐diazepino[3,4‐b]‐quinoxalines 7a‐d . The reaction of compounds 7a and 7b with diethyl azodicarboxylate effected dehydrogenation to give the 5‐alkoxy‐8‐chloro‐4,6‐dihydro‐1‐methyl‐4‐oxo‐3‐(2‐thienyl)‐1H‐1,2‐diazepino[3,4‐b]‐quinoxalines 8a and 8b , respectively. Compounds 8a and 8b were found to show good algicidal activities against Selenastrum capricornutum and Nitzchia closterium. 相似文献
3.
Djamila Hikem‐Oukacha Yahïa Rachedi Maamar Hamdi Artur M.S. Silva 《Journal of heterocyclic chemistry》2011,48(1):31-37
An efficient synthesis of 3‐bromoacetyl‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one by bromination of dehydroacetic acid in glacial acetic acid is described. Novel 4‐hydroxy‐6‐methyl‐3‐(2‐substituted‐thiazol‐4‐yl)‐2H‐pyran‐2‐ones have been prepared from the reaction of 3‐bromoacetyl‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one with thioamides, thiourea, and diphenylthiocarbazone. The condensation reaction of 6‐methyl‐4H‐furo[3,2c]pyran‐3,4‐dione, obtained from the reaction of 3‐bromoacetyl‐4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one with aliphatic amines, with benzaldehydes and acetophenones led to novel 2‐arylidene‐6‐methyl‐2H‐furo[3,2‐c]pyran‐3,4‐diones and 6‐(2‐arylprop‐1‐enyl)‐2H‐furo[3,2‐c]pyran‐3,4‐diones. The structure of all compounds was established by elemental analysis, IR, NMR, and mass spectra. J. Heterocyclic Chem., 2011. 相似文献
4.
《Journal of heterocyclic chemistry》2017,54(4):2405-2416
3(5)‐Aminopyrazole derivative ( 6 ) has been synthesized by the reactions of the versatile unreported 2‐cyano‐N ′‐(1‐(3‐methyl‐6‐phenylimidazo[2,1‐b ]thiazol‐2‐yl)ethylidene)acetohydrazide ( 3 ) with phenyl isothiocyanate in KOH/DMF solution followed by reaction with methyl iodide and hydrazine hydrate. Reaction of compound 6 with some 1,3‐dicarbonyl compounds yielded pyrazolo[1,5‐a ]pyrimidine derivatives ( 14 – 17 ). Alkylation of compound 6 with various halo reagents, followed by intramolecular cyclization, yielded the corresponding imidazo[1,2‐b ]pyrazole derivatives 27 , 29 , 31 , and 33 . All newly synthesized compounds were elucidated by considering the data of both elemental analysis and spectral data. 相似文献
5.
Henrieta Stankovi
ov Anton Gplovský Margita Lcov Jarmila Chovancov Agnieszka Puchala 《Journal of heterocyclic chemistry》2006,43(4):843-848
6.
A Convenient and Facile Synthesis of Isoxazolyl‐chromeno[4,3,2‐de]pyrimido[4,5‐h][1,6]napthyridinones
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Eligeti Rajanarendar Saini Ramakrishna Baireddy Kishore 《Journal of heterocyclic chemistry》2014,51(5):1415-1420
The ceric ammonium nitrate‐catalyzed synthesis of (E)‐5‐amino‐N‐(3‐methyl‐5‐styrylisoxazol‐4‐yl)‐2‐arylchromeno[4,3,2‐de][1,6]napthyridin‐4‐carboxamides 5 was simply achieved upon the one‐pot four‐component reaction of isoxazolyl cyanoacetamide 1 with malononitrile 2 , 2‐hydroxy acetophenone 3 , and aromatic aldehydes 4 in ethanol. Compounds 5 on heating with acetic anhydride underwent tandem N‐acetylation and cyclocondensation involving intramolecular cyclization to afford the title compounds (E)‐11‐methyl‐12‐(3‐methyl‐5‐styrylisoxazol‐4‐yl)‐2‐arylchromeno[4,3,2‐de][1,6]napthyridin‐13(12H)‐ones 6 in good yields. The chemical structures have been confirmed by analytical and spectral analyses. 相似文献
7.
Strategy to Construct Stair‐Shaped Partially Reduced Naphtho[1,2‐b]pyrano[2,3‐d]oxepines and Dinaphtho[1,2‐b,d]oxepines
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Sanjay K. Gautam Hardesh K. Maurya Ramendra Pratap Brijesh Kumar Abhinav Kumar Vishnu K. Tandon Vishnu Ji Ram 《Journal of heterocyclic chemistry》2016,53(6):2070-2078
A concise and efficient base‐induced synthesis of stair‐shaped, 4‐methylthio‐2‐oxo‐5,6‐dihydro‐2H‐naphtho[1,2‐b]pyran[2,3‐d]oxepine‐3‐carbonitriles ( 3 ) has been delineated by the reaction of 3,4‐dihydronaphtho[1,2‐b]oxepin‐5(2H)‐one ( 1 ) and methyl 2‐cyano‐3,3‐dimethylthioacrylate in DMSO using powdered KOH as a base at room temperature. Amination of 3 has been achieved by reaction with secondary amine in ethanol at reflux temperature to yield 4‐sec‐amino‐2‐oxo‐5,6‐dihydro‐2H‐naphtho[1,2‐b]pyran[2,3‐d]oxepine‐3‐carbonitriles ( 4 ). Reaction of 3 with aryl methyl ketone ( 5 ) in DMSO at room temperature using powdered KOH as a base produced stair‐shaped 5‐aryl‐7,8‐dihydro‐1,4‐dioxa‐2,3‐dioxodinaphtho[1,2‐b,d]oxepine ( 6 ) in good yields. However, reaction of 6‐aryl‐2H‐pyran‐2‐one‐3‐carbonitrile ( 8 ) with 3,4‐dihydronaphtho[1,2‐b]oxepin‐5(2H)‐one ( 1 ) did not give similar product, but in lieu 4‐aryl‐5,6‐dihydronaphtho[1,2‐b]oxepino[4,5‐b]pyran‐2‐ylidene)acetonitrile ( 9 ) was isolated and characterized. 相似文献
8.
Mohamed R. Shaaban Taha M. A. Eldebss Ahmed F. Darweesh Ahmad M. Farag 《Journal of heterocyclic chemistry》2008,45(6):1739-1744
9.
Ethyl 7‐amino‐3‐(3‐methyl‐5‐oxo‐1‐phenyl‐2‐pyrazolin‐4‐yl)‐5‐aryl‐5H‐thiazolo[3,2‐a]pyrimidine‐6‐carboxylate was hydrolyzed with an ethanolic sodium hydroxide and the sodium salt thus formed underwent cyclization with acetic anhydride to afford 2‐methyl‐7‐(3‐methyl‐5‐oxo‐1‐phenyl‐2‐pyrazolin‐4‐yl)‐5‐arylthiazolo[3,2‐a]pyrimido[4,5‐d]oxazin‐4(5H)‐one. This compound was transformed to related heterocyclic systems via its reaction with various reagents. The biological activity of the prepared compounds was tested against Gram positive and Gram negative bacteria as well as yeast‐like and filamentous fungi. They revealed in some cases excellent biocidal properties. 相似文献
10.
Syntheses of New Unsymmetrical 2,5‐Disubstituted‐1,3,4‐oxadiazoles and 1,2,4‐Triazolo[3,4‐b]‐1,3,4‐thiadiazoles Bearing Thieno[2,3‐c]pyrazolo Moiety
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Shivaraj P. Patil Shrikant B. Kanawade Dinesh C. Bhavsar Prashant S. Nikam Sachin A. Gangurde Raghunath B. Toche 《Journal of heterocyclic chemistry》2014,51(2):368-373
New series of (thieno[2,3‐c]pyrazolo‐5‐yl)‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazoles 10a , 10b , 10c and (thieno[2,3‐c]pyrazol‐5‐yl)‐1,3,4‐oxadiazol‐3(2H)‐yl)ethanones 6a , 6b , 6c has been synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by multistep reaction sequence. (5‐Aryl‐1,3,4‐oxadiazol‐2‐yl)‐1H‐thieno[2,3‐c]pyrazoles 4a , 4b , 4c were also synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by cyclization with various aromatic carboxylic acids. The hydrazide 3 was obtained by reaction of thieno[2,3‐c]pyrazole‐5‐carboxylate 2 with hydrazine hydrate in good yield, and compound 2 was obtained by the reaction of 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde 1 and 2‐ethyl thioglycolate in presence of sodium alcoholate in good yield. 相似文献
11.
This paper presents the synthesis of a series of 5,6‐dihydro‐4H,8H‐pyrimido[1,2,3‐cd]purine‐8,10(9H)‐dione ring system derivatives with a [1,2,3]triazole ring bonded in position 2. The procedure is based on cycloaddition of substituted alkyl azides to the terminal triple bond of 5,6‐dihydro‐2‐ethynyl‐9‐methyl‐4H,8H‐pyrimido[1,2,3‐cd]purine‐8,10(9H)‐dione ( 4 ). This cycloaddition produced two regioisomers ?5,6‐dihydro‐9‐methyl‐2‐(1‐substituted‐1H‐[1,2,3]triazol‐5‐yl)‐4H,8H‐pyrimido[1,2,3‐cd]purine‐8,10(9H)‐dione ( 7 ) and 2‐(1‐substituted‐1H‐[1,2,3]triazol‐4‐yl) derivative 8 . The required 2‐ethynyl deriva tive 4 was obtained from the starting 2‐unsubstituted compound 1 by bromination to yield the 2‐bromo derivative 2 , which was converted by Sonogashira reaction to trimethylsilylethyne 3 and finally, the protective trimethylsilyl group was removed by hydrolysis. 相似文献
12.
Eligeti Rajanarendar Paka Venkateshwarlu Saini Ramakrishna Dharavath Nagaraju 《Journal of heterocyclic chemistry》2015,52(4):1007-1013
Synthesis of novel 2‐3‐methyl‐5‐[(E)‐2‐aryl‐1‐ethenyl]‐4‐isoxazolyl‐4,10a‐diaryl‐1,10a‐dihydro‐2H‐benzo[d]pyrazino[2,1‐b][1,3]oxazoles 5 were simply achieved by the reaction of 2‐[3‐methyl‐5‐[(E)‐2‐aryl‐1‐ethenyl]‐4‐isoxazolyl(2‐oxo‐2‐arylethyl)amino]‐1‐aryl‐1‐ethanones 3 with o‐aminophenol 4 in the presence of CAN catalyst. The intermediates, 2‐[3‐methyl‐5‐[(E)‐2‐aryl‐1‐ethenyl]‐4‐isoxazolyl(2‐oxo‐2‐arylethyl)amino]‐1‐aryl‐1‐ethanones 3 , were prepared by the reaction of 4‐amino‐3‐methyl‐5‐styrylisoxazole 1 , with phenacylbromides 2 in ethanol in the presence of K2CO3. The structures of the newly synthesized compounds 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , 3l and 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j , 5k , 5l have been confirmed by analytical and spectral data. 相似文献
13.
Mohamed Salah K. Youssef Mohamed S. Abbady Ragaa A. Ahmed Ahmed A. Omar 《Journal of heterocyclic chemistry》2013,50(2):179-187
Ethyl 7‐amino‐3‐(3‐methyl‐5‐oxo‐1‐phenyl‐2‐pyrazolin‐4‐yl)‐5‐aryl‐5H‐thiazolo[3,2‐a]pyrimidine‐6‐carboxylate was synthesized by the reaction of 4‐(2‐aminothiazol‐4‐yl)‐3‐methyl‐5‐oxo‐1‐phenyl‐2‐pyrazoline with arylidene ethyl cyanoacetate and it transformed to related fused heterocyclic systems via reaction with various reagents. The biological activities of these compounds were evaluated. 相似文献
14.
Microwave‐assisted Synthesis of 6‐{(5‐Aryl‐1,3,4‐oxadiazol‐2‐yl)methyl}‐6H‐indolo[2,3‐b]quinoxalines
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Sreenivas Avula Jayaram Reddy Komsani Satish Koppireddi Rambabu Yadla 《Journal of heterocyclic chemistry》2015,52(6):1737-1742
An efficient and convenient synthesis of a new series of 2‐{(6H‐indolo[2,3‐b]quinoxalin‐6‐yl)methyl}‐5‐aryl‐1,3,4‐oxadiazoles from readily available 1,2‐diaminobenzene and isatins under microwave irradiation conditions was disclosed. The 6‐{(5‐aryl‐1,3,4‐oxadiazol‐2‐yl)methyl}‐6H‐indolo[2,3‐b]quinoxalines were also prepared by the thermal cyclo‐condensation reaction of 2‐(6H‐indolo[2,3‐b]quinoxalin‐6‐yl)acetohydrazides with carboxylic acids in refluxing POCl3. The microwave‐assisted synthesis was rapid and resulted in higher yield of the products at lower operating temperature with reduced waste generation in comparison with the thermal reaction protocol. 相似文献
15.
A. Shafiee J. Shahbazi Mojarrad M. A. Jalili H. R. Adhami F. Hadizadeh 《Journal of heterocyclic chemistry》2002,39(2):367-373
Starting from readily available p‐substituted‐benzylamines a series of ethyl 2‐alkylthio‐1‐substituted‐ben‐zylpyrrolo[2,3‐d]imidazole‐5‐carboxylates was prepared. In addition, starting from 2‐alkyl‐4(or 5)‐formylimidazoles and methyl 4′‐bromomethylbiphenyl‐2‐carboxylate a series of methyl substituted‐pyrrolo[2,3‐d]imidazole‐5‐carboxylates and methyl substituted‐pyrrolo[3,2‐d]imidazole‐5‐carboxylates was prepared. 相似文献
16.
Shambabu Joseph Maddirala Vidya S. Gokak Linganagouda D. Basanagoudar 《Journal of heterocyclic chemistry》2004,41(1):7-11
3‐Benzylindole‐2‐carbohydrazides (4) on reaction with triethylorthoformate in a polar solvent like DMF yielded only 10‐benzyl‐1,2‐dihydro‐1‐oxo‐1,2,4‐triazino[4,5‐a]indoles (5) while (4) on reaction with triethylorthoacetate in DMF yielded both 10‐benzyl‐4‐methyl‐1,2‐dihydro‐1‐oxo‐1,2,4‐triazino[4,5‐a]indoles (5) and 3‐benzyl‐2‐(5‐methyl‐1,3,4‐oxadiazol‐2‐yl)indoles (6) instead of only the triazinoindoles as expected. The oxadiazolylindoles (6) were also synthesized by refluxing (4) with excess of orthoesters. The structures of the compounds formed were characterized by their analytical and spectral data. 相似文献
17.
Zhengbing Pan Hui Xu Kaimin Mao Lei Dai Liming Zhao Liangce Rong 《Journal of heterocyclic chemistry》2019,56(4):1393-1402
In this research, we have developed an efficient three‐component reaction for the synthesis of pyrano[3,2‐c]pyridine derivatives from the reaction of aromatic aldehydes, tert‐butyl 2,4‐dioxopiperidine‐1‐carboxylate, and N‐methyl‐1‐(methylthio)‐2‐nitroethylen‐1‐amine in [BMIM]BF4 medium. The advantages of this method were readily available starting materials, simple reaction conditions, and satisfactory yields. 相似文献
18.
Synthesis of Novel 3‐(3‐(5‐Methylisoxazol‐3‐yl)‐7H‐[1,2,4]Triazolo [3,4‐b][1,3,4]Thiadiazin‐6‐yl)‐2H‐Chromen‐2‐Ones
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A novel series of coumarin substituted triazolo‐thiadiazine derivatives were designed and synthesized by using 5‐methyl isoxazole‐3‐carboxylic acid ( 1 ), thiocarbohydrazide ( 2 ), and various substituted 3‐(2‐bromo acetyl) coumarins ( 4a , 4b , 4c , 4e , 4d , 4f , 4g , 4h , 4i , 4j ). Fusion of 5‐methyl isoxazole‐3‐carboxylic acid with thiocarbohydrazide resulted in the formation of the intermediate 4‐amino‐5‐(5‐methylisoxazol‐3‐yl)‐4H‐1,2,4‐triazole‐3‐thiol ( 3 ). This intermediate on further reaction with substituted 3‐(2‐bromo acetyl) coumarins under simple reaction conditions formed the title products 3‐(3‐(5‐methylisoxazol‐3‐yl)‐7H‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazin‐6‐yl‐2H‐chromen‐2‐ones ( 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j ) in good to excellent yields. All the synthesized compounds were well characterized by physical, analytical, and spectroscopic techniques. 相似文献
19.
《Journal of heterocyclic chemistry》2018,55(1):91-96
Reaction of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione ( 1 ) with two equivalents of some 6‐aminouracils (or 6‐amino‐2‐thiouracil) generates spirocyclic tetrahydrobenzo[if]quinolizines ( 7 ). The one‐pot, three‐component reaction of amido ketone ( 1 ) with 6‐aminouracil (or 6‐amino‐2‐thiouracil) and a cyclic six‐membered 1,3‐diketone produces spirocyclic tetrahydropyrrolo[3,2,1‐ij]quinolinones ( 15 ). 相似文献
20.
Two series of 7‐arylazo‐7H‐3‐(2‐methyl‐1H‐indol‐3‐yl)pyrazolo[5,1‐c][1,2,4]triazol‐6(5H)‐ones 4 and 7‐arylhydrazono‐7H‐3‐(2‐methyl‐1H‐indol‐3‐yl)‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazines 7 were prepared via reactions of 4‐amino‐3‐mercapto‐5‐(2‐methyl‐1H‐indol‐3‐yl)‐1,2,4‐triazole 1 with ethyl arylhydrazono‐chloroacetate 2 and N‐aryl‐2‐oxoalkanehydrazonoyl halides 5 , respectively. A possible mechanism is proposed to account for the formation of the products. The biological activity of some of these products was also evaluated. 相似文献