首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Reactions of magnesium 3‐tert‐butyl‐8‐R‐4‐oxo‐4H‐pyrazolo[5,1‐c][1,2,4]triazin‐1‐ides (R = CN, CO2Et) with AlkMgBr led to nucleophilic additions to either side chain or triazine core, with selectivity being dependent on the nature of substituents, as well as on the solvents used. Previously inaccessible C8‐functionalized and C4‐functionalized pyrazolo[5,1‐c][1,2,4]triazines and 3‐tert‐butyl‐3‐ethyl‐4‐oxo‐1,2,3,4‐tetrahydropyrazolo[5,1‐c][1,2,4]triazine were synthesized, and their reactivity and spectral data discussed.  相似文献   

2.
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   

3.
The novel heterocyclizations of ethyl 5‐(hydrazinocarbonyl)‐2,4‐dimethyl‐1H‐pyrrole‐3‐carboxylate are developed. New derivatives of ethyl esters of 4‐R‐6,8‐dimethyl‐1‐oxo‐1,2‐dyhidropyrrolo[1,2‐d][1,2,4]triazine‐7‐carboxylic acids were obtained. The in vitro anticancer and antibacterial activities of the synthesized compounds were revealed. The most potent antibacterial compound appeared to be 1.3 inhibiting Staphylococcus aureus. Pyrrolo[1,2‐d][1,2,4]triazine 2.15 showed significant antifungal activity against Candida tenuis. The anticancer activity of the synthesized compounds was determined.  相似文献   

4.
Oxidation of 3,4-di-tert-butyl-8-methyl-1,4-dihydropyrazolo[5,1-c][1,2,4]triazine with NBS/K2CO3 furnished 3,4-di-tert-butyl-8-methylpyrazolo[5,1-c][1,2,4]triazine, a mildly strained heteroaromatic compound. X-Ray single crystal diffraction analysis indicated that the conjugated 1,2,4-triazine ring adopts a twist-boat configuration, while the two t-Bu substituents are located on the opposite sides of the azole plane. The related 3-tert-butyl-4-(o-C-carboranyl)-8-methyl-1,4-dihydropyrazolo[5,1-c][1,2,4]triazine was also synthesized, however, its oxidative aromatization was unsuccessful.  相似文献   

5.
Novel [1,2,4]triazole derivatives were synthesized via various synthetic pathways. Among which were different substituted [1,2,4]triazole analogues that were synthesized, in addition to various fused [1,2,4]triazolo[1,5‐a]pyrimidine derivatives, [1,2,4]triazolo[1,5‐a][1,3,5]triazines, and [1,2,4]triazolo[5,1‐c][1,2,4]triazines. Besides, benzo[h][1,2,4]triazolo[5,1‐b]quinazolines, [1,2,4]triazolo‐[5,1‐b]quinazoline, [1,2,4]triazolo[1,5‐a]quinazoline and [1,2,4]triazolo[5,1‐d][1,2,3,5]tetrazine derivatives were also synthesized. The newly synthesized compounds were evaluated for their in vitro anticancer activity against liver cancer HepG2 and breast cancer MCF7 cell lines compared with the reference drug doxorubicin. Compounds 4 , 7 , 15 , 17 , 28 , 34 , and 47 were found to exert promising anticancer activity against HepG2 cell line showing IC50 values ranging from 17.69 to 25.4 μM/L, while compounds 7 , 14a , 17 , 28 , and 34 showed significant activity against MCF7 cell line with IC50 values ranging from 17.69 to 27.09 μM/L.  相似文献   

6.
The reaction of 3‐amino‐5‐nitro‐1,2,4‐triazole with nitrous acid produces the corresponding diazonium salt. When the diazonium salt is treated with nitroacetonitrile, a subsequent condensation and cyclization reaction occurres to produced 4‐amino‐3,7‐dinitrotriazolo‐[5,1‐c][1,2,4] triazine (DPX‐26). X‐ray crystallographic analysis shows that the DPX‐26 has a density of 1.86 g cm?3, while it is calculated to have a heat of formation of 398.3 kJ mol?1. DPX‐26 is predicted to approach the explosive performance of RDX but displays significantly better safety properties. Oxidation of DPX‐26 using hypofluorous acid produces 4‐amino‐3,7‐dinitrotriazolo‐[5,1‐c][1,2,4] triazine 4‐oxide (DPX‐27), which is also predicted to be a high‐performance material with enhanced safety properties.  相似文献   

7.

Ethyl 3-tert-butyl-4-oxo-7-X-4,6-dihydropyrazolo[5,1-c][1,2,4]triazine-8-carboxylates (X = H, Cl, Br) were synthesized for the first time by diazotization of 7-amino-3-tert-butyl-4oxo-8-ethoxycarbonyl-6H-pyrazolo[5,1-c][1,2,4]triazines with tert-butyl nitrite in the presence of trimethylsilyl halides. A new method was developed: a reaction between 7-amino-3-tert-butyl-4-oxo-6H-pyrazolo[5,1-c][1,2,4]triazine-8-carboxylic acid and I2/TEA followed by treatment with NaBH4 led to a mild decarboxylation. The acid reacts with N-halosuccinimides to give novel 8-halo-substituted derivatives. The amino groups of the latter were acylated by treatment with trifluoroacetic anhydride to give monoacylation products.

  相似文献   

8.
New 1,2,4‐triazine and their derived 1,2,4‐triazolo[3,4‐b][1,2,4]triazine derivatives were synthesized starting from 5,6‐diphenyl‐1,2,4‐triazine‐3‐thiol. Furthermore, the corresponding 1,2,4‐triazolo[3,4‐b][1,2,4]‐triazine thioglycosides and acyclic C‐nucleoside analogs were synthesized. The newly synthesized compounds were evaluated for their antitumor activity and some of them showed high inhibition activities. J. Heterocyclic Chem., 2011.  相似文献   

9.
Treatment of ethyl 7-amino-3-tert-butyl-4-oxo-4,6-dihydropyrazolo[5,1-c][1,2,4]triazine-8-carboxylate with P2S5 in pyridine gave ethyl 7-amino-3-tert-butyl-4-thioxo-4,6-dihydropyrazolo[5,1-c][1,2,4]triazine-8-carboxylate which was subjected to acylation, decarboxylation, and hydrazinolysis.  相似文献   

10.
The ester group in ethyl 7-amino-3-tert-butyl-4-oxo-4,6-dihydropyrazolo[5,1-c][1,2,4]triazine-8-carboxylate was converted for the first time to methyl by the action of lithium tetrahydridoborate in the presence of boron trifluoride–diethyl ether complex. This reaction has almost no analogies among other classes of organic compounds. New difficultly accessible 7-chloro and 7-azido derivatives were synthesized via diazotization of the reduction product, and treatment of the latter with acetic anhydride afforded the exhaustively acetylated derivative. Diazotization of ethyl 7-amino-3-tert-butyl-4-oxo-4,6-dihydropyrazolo-[5,1-c][1,2,4]triazine-8-carboxylate, followed by reaction with sodium azide, gave the corresponding azide, and the product of azo coupling with ethyl acetoacetate failed to undergo intramolecular cyclization to tricyclic pyrazolo[3,2-c: 5,1-c′]bis[1,2,4]triazine system.  相似文献   

11.
In an attempt to discover bicyclic compounds containing the 1,2,4‐triazine moiety, 1,2,4‐triazolo[1,5‐d]‐1,2,4‐triazine‐5‐thiones from one pot reaction of arylnitriles with 4‐amino‐1,2,4‐triazine‐3‐thione‐5‐one in the presence of potassium tert‐butoxide were synthesized.  相似文献   

12.
The reaction of 3‐N‐(2‐mercapto‐4‐oxo‐4H‐quinazolin‐3‐yl)acetamide ( 1 ) with hydrazine hydrate yielded 3‐amino‐2‐methyl‐3H‐[1,2,4]triazolo[5,1‐b]quinazolin‐9‐one ( 2 ). The reaction of 2 with o‐chlorobenzaldehyde and 2‐hydroxy‐naphthaldehyde gave the corresponding 3‐arylidene amino derivatives 3 and 4 , respectively. Condensation of 2 with 1‐nitroso‐2‐naphthol afforded the corresponding 3‐(2‐hydroxy‐naphthalen‐1‐yl‐diazenyl)‐2‐methyl‐3H‐[1,2,4]triazolo[5,1‐b]quinazolin‐9‐one ( 5 ), which on subsequent reduction by SnCl2 and HCl gave the hydrazino derivative 6. Reaction of 2 with phenyl isothiocyanate in refluxing ethanol yielded thiourea derivative 7. Ring closure of 7 subsequently cyclized on refluxing with phencyl bromide, oxalyl dichloride and chloroacetic acid afforded the corresponding thiazolidine derivatives 8, 9 and 10 , respectively. Reaction of 2‐mercapto‐3‐phenylamino‐3H‐quinazolin‐4‐one ( 11 ) with hydrazine hydrate afforded 2‐hydrazino‐3‐phenylamino‐3H‐quinazolin‐4‐one ( 12 ). The reactivity 12 towards carbon disulphide, acetyl acetone and ethyl acetoacetate gave 13, 14 and 15 , respectively. Condensation of 12 with isatin afforded 2‐[N‐(2‐oxo‐1,2‐dihydroindol‐3‐ylidene)hydrazino]‐3‐phenylamino‐3H‐quinazolin‐4‐one ( 16 ). 2‐(4‐Oxo‐3‐phenylamino‐3,4‐dihydroquinazolin‐2‐ylamino)isoindole‐1,3‐dione ( 17 ) was synthesized by the reaction of 12 with phthalic anhydride. All isolated products were confirmed by their ir, 1H nmr, 13C nmr and mass spectra.  相似文献   

13.
A series of 2‐substituted 2H‐thieno[3,4‐e][1,2,4]thiadiazin‐3(4H)‐one 1,1‐dioxides ( 2 ), 2‐substituted 2H‐thieno[2,3‐e][1,2,4]thiadiazin‐3(4H)‐one 1,1‐dioxides ( 3 ), 2‐substituted 4,6‐dihydropyrazolo[4,3‐e]‐[1,2,4]thiadiazin‐3(2H)‐one 1,1‐dioxides ( 4 ), 2‐substituted 2,3‐dihydrooxazolo[3,2‐b]thieno[3,4‐e]‐[1,2,4]thiadiazine 5,5‐dioxides, ( 5 ), 6‐substituted 6,7‐dihydro‐2H‐oxazolo[3,2‐b]pyrazolo[4,3‐e][1,2,4]thia‐diazine 9,9‐dioxides ( 6 ) and 7‐substituted 6,7‐dihydro‐2H‐oxazolo[3,2‐b]pyrazolo[4,3‐e][1,2,4]thiadiazine 9,9‐dioxides ( 7 ) were synthesized as potential psychotropic agents.  相似文献   

14.
E‐3‐(N,N‐Dimethylamino)‐1‐(3‐methylthiazolo[3,2‐a]benzimidazol‐2‐yl)prop‐2‐en‐1‐one ( 2 ) was synthesized by the reaction of 1‐(3‐methylthiazolo[3,2‐a]benzimidazol‐2‐yl)ethanone ( 1 ) with dimethylformamide‐dimethylacetal. The reaction of 2 with 5‐amino‐3‐phenyl‐1H‐pyrazole ( 4a ) or 3‐amino‐1,2,4‐(1H)‐triazole ( 4b ) furnished pyrazolo[1,5‐a]pyrimidine and 1,2,4‐triazolo[1,5‐a]pyrimidine derivatives 6a and 6b , while the reaction of enaminone 2 with 6‐aminopyrimidine derivatives 7a,b afforded pyrido[2,3‐d]pyrimidine derivatives 9a,b , respectively. The diazonium salts 11a or 11b coupled with compound 2 to yield the pyrazolo[5,1‐c]‐1,2,4‐triazine and 1,2,4‐triazolo[5,1‐c]‐1,2,4‐triazine derivatives 13a and 13b . Some of the newly synthesized compounds exhibited a moderate effect against some bacterial and fungal species.  相似文献   

15.
Azo coupling of 1,3‐dicarbonyl compounds with tetrazolyl‐5‐diazonium chloride is used to develop a convenient one‐step procedure for the synthesis of 4,7‐dihydrotetrazolo[5,1‐c][1,2,4]triazines. In contrast to nonfluorinated analogs, 7‐hydroxy‐7‐polyfluoroalkyl‐4,7‐dihydrotetrazolo[5,1‐c][1,2,4]triazines undergo a ring‐chain isomerism resulting from the cleavage at the C7―N7a bond. A distinctive feature of nonfluorinated 4,7‐dihydrotetrazolo[5,1‐c][1,2,4]triazines is the possibility to dehydration, which is accompanied by an azide rearrangement due to the tetrazole ring cleavage with the formation of tetrazolo[1,5‐b][1,2,4]triazines.  相似文献   

16.
2‐Acetyl‐5,7‐dibromobenzo[b]furan ( 1 ) reacted with dimethylformamide‐dimethylacetal to give the corresponding (E)‐enaminone 3 which coupled with aromatic diazonium chloride to afford the corresponding key intermediates 3‐oxo‐2‐(2‐arylhydrazono)propanals 6a , b . Compounds 6a , b were used to prepare novel 3‐imino‐2,3‐dihydropyridazines 10a , b and 6‐phenylazopyrido[2,3‐d]pyrimidin‐4(1H)‐one derivatives 15a , b through their reaction with acetonitrile derivatives 8a , b and 6‐aminopyrimidin‐4(1H)‐one 13 , respectively. On the other hand, the enaminone 3 was taken as a synthetic precursor to synthesize novel pyrazolo[5,1‐c][1,2,4]triazines 21a – c , [1,2,4]triazolo[3,4‐c][1,2,4]triazines 25 and benzimidazo[2,1‐c][1,2,4]triazine 29 containing 5,7‐dibromobenzofuran‐2‐oyl moiety via its coupling with the appropriate diazonium salts of a variety of hetero‐armomatic amines in a facile one‐step route.  相似文献   

17.
The present study emphasizes on the dealklylation of 3‐aryl‐5‐alkyl‐2‐oxo‐Δ4‐1,3,4‐oxadiazoles when reacted with formamide resulting in the formation of 2‐aryl‐2H‐1,2,4‐triazol‐3(4H )‐ones as major product. Subsequent reactions of 2‐aryl‐2H‐1,2,4‐triazol‐3(4H )‐one gave triazolo[3,4‐b ][1,3,4]thiadiazoles and triazolo[3,4‐b ][1,3,4]thiadiazines derivatives incorporated with 1,2,4‐triazol‐3‐one.  相似文献   

18.
The reactions of the pyrazole-5-diazonium salt 3 with malononitrile and ethyl cyanoacetate gave 4-amino-3-cyano-8-ethoxycarbonylpyrazolo[5,1-c][1,2,4]triazine 7 and 4-amino-3,8-bisethoxycarbonylpyrazolo[5,1-c]-[1,2,4]triazine 8 , whose reactions with p-chloroaniline hydrochloride afforded 4-amino-8-ethoxycarbonyl-3-(p-chlorophenyl)amidinopyrazolo[5,1-c][1,2,4]triazine 9 and 4-amino-8-ethoxycarbonyl-3-(p-chlorophenyl)car-bamoylpyrazolo[5,1-c][1,2,4]triazine 10 , respectively. The reactions of 7 and 8 with o-phenylenediamine di-hydrochloride provided 9-ethoxycarbonyl-13H-spiro[benzimidazole-2′(3′H),6(5H)-pyrazolo[1,5′:3,4][1,2,4]tri-azino[5,6-b][1,5]benzodiazepine] hydrochloride 11a and 9-ethoxycarbonyl-6-oxo-13H-5,6-dihydropyrazolo-[1′,5′:3,4][1,2,4]triazino[5,6-b][1,5]benzodiazepine 12 , respectively. The antifungal activity of the above compounds was described.  相似文献   

19.
By reaction of carbonyl compounds with 7-amino-3-tert-butyl-4-oxo-4,6-dihydropyrazolo[5,1-c]-[1,2,4]triazine-8-carbonitrile 3-tert-butyl-8-R-4,6,9,10-tetrahydropyrimido[4′,5′:3,4]pyrazolo[5,1-c][1,2,4]-triazine-4,10-diones and (3-tert-butyl-4-oxo-8-cyano-4,6-dihydropyrazolo[5,1-c][1,2,4]triazin-7-yl)acetamide were obtained.  相似文献   

20.
The first stable compound containing both N2+BF4? and CON3 functional groups – 8-azidocarbonyl-3-(tert-butyl)-4-oxo-4,6-dihydropyrazolo[5,1-c][1,2,4]triazine-7-diazonium tetrafluoroborate was synthesized, and its stability and reactivity discussed. The Curtius rearrangement of 7-azido-3-(tert-butyl)-4-oxo-4,6-dihydropyrazolo[5,1-c][1,2,4]triazine-8-carbonylazide was investigated, and the synthesis of a novel heterocyclic system –pyrazino[2′,3′:3,4]pyrazolo[5,1-c][1,2,4]triazin-4(6H)-one is described.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号