Synthesis of some new pyrazolo[1,5-a]pyrimidine and pyrazolo[1,5-c]-as-triazine derivatives

1986 ◽  
Vol 51 (10) ◽  
pp. 2193-2198 ◽  
Author(s):  
Abdel Ghani A. Elagamey ◽  
Fathy M. A. El-Taweel ◽  
F. A. Amer
Keyword(s):  
Hydrazine Hydrate ◽  
Diazonium Salt ◽  
Triazine Derivatives ◽  
Active Methylene

Several new pyrazolo[1,5-a]pyrimidine and pyrazolo[1,5-c]-as-triazine derivatives were synthesized via the reaction of 3-antipyrinyl-5-aminopyrazole or its diazonium salt with enaminonitriles, enaminoesters and active methylene reagents. The action of hydrazine hydrate on the obtained polyfunctional products was also studied.

scholarly journals A Facile Synthesis of Pyrido[2′,3′:3,4]pyrazolo[1,5-a]pyrimidine and Pyrido[2′,3′:3,4]pyrazolo[5,1-c][1,2,4]triazine Bearing a Thiophene Moiety

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Tilal Elsaman ◽  
Mohamed Fares ◽  
Hatem A. Abdel-Aziz ◽  
Mohamed I. Attia ◽  
Hazem A. Ghabbour ◽  
...  
Keyword(s):  
Hydrazine Hydrate ◽  
Diazonium Salt ◽  
Facile Synthesis ◽  
Amine Derivative ◽  
Thiophene Moiety ◽  
Active Methylene

Pyridinone derivative8was synthesized and transformed into the respective chloropyridine9, which was allowed to react with hydrazine hydrate to afford pyrazolo[3,4-b]pyridin-3-amine derivative11. Compound11was used as a key intermediate for a facile synthesis of the title compounds14,15,17,21a,b, and24a–cwhere the reaction of11with some 1,3-dielecrophiles resulted in the formation of pyrido[2′,3′:3,4]pyrazolo[1,5-a]pyrimidines14,15, and17, whereas diazotization of compound11gave the respective diazonium salt18which was coupled with some active methylene-containing compounds to give the corresponding hydrazones19a,band22a–c. Cyclization of the latter hydrazones yielded the pyrido[2′,3′:3,4]pyrazolo[5,1-c][1,2,4]triazines21a,band24a–c, respectively.

Reactions of ferrocenyl chalcones with hydrazines and active methylene compounds

2016 ◽  
Vol 22 (2) ◽  
pp. 69-77 ◽  
Author(s):  
Marwa El-Hussieny ◽  
Hisham Abdallah A. Yosef ◽  
Mohamed R.H. Mahran ◽  
Nabila M. Ibrahim
Keyword(s):  
Hydrazine Hydrate ◽  
Reaction Mechanisms ◽  
Ethyl Acetoacetate ◽  
New Products ◽  
Ethyl Cyanoacetate ◽  
Spectroscopic Methods ◽  
Phenyl Hydrazine ◽  
Active Methylene Compounds ◽  
Ferrocenyl Chalcones ◽  
Active Methylene

AbstractClaisen-Schmidt condensation of ferrocenecarboxaldehyde (2b) with 2-acetylfuran (4) yielded (E)-3-ferrocenyl-1-(2-furyl)prop-2-en-1-one (E-5) together with 1,5-di(2-furyl)-3-ferrocenylpentane-1,5-dione (6). Reactions of the ferrocenyl chalcones 3a,b and 5 with hydrazine hydrate, phenyl hydrazine, ethyl acetoacetate, ethyl cyanoacetate and malononitrile, were also studied. Possible reaction mechanisms were discussed and structures of the new products were unambiguously characterized by common analytical and spectroscopic methods.

Reactions with Heterocyclic Diazonium Salts, II Synthesis of Some New Pyrazolo[1,5-c]-as-triazines and 1,2,4-Triazolo[1,5-c] -as-triazines

1978 ◽  
Vol 33 (2) ◽  
pp. 216-219 ◽  
Author(s):  
Mohamed Hilmy Elnagdi ◽  
Mohamed Rifaat Hamza Elmoghayar ◽  
Shereif Mahmoud Fahmy ◽  
Mohamed Kamal Ahmed Ibraheim ◽  
Hikmat Hussein Alnima
Keyword(s):  
Water Treatment ◽  
Sulphuric Acid ◽  
Sodium Acetate ◽  
Diazonium Salts ◽  
Aqueous Sodium ◽  
Triazine Derivative ◽  
Mechanism Of Reaction ◽  
Active Methylene Compounds ◽  
Triazine Derivatives ◽  
Active Methylene

3-Phenylpyrazole-5-diazonium chloride (2) couples with benzoylacetonitrile and with phenacylthiocyanate to yield the corresponding hydrazone derivatives 3 a, b. Whereas 3 a cyclised into the pyrazolo[1,5-c]-as-triazine derivative (4a) upon treatment with concentrated sulphuric acid via elimination of water, treatment of 3 b with the same reagent under the same conditions has resulted in elimination of thiocyanic acid and the formation of the pyrazolo[1,5-c]-as-triazine derivative (4b).Treatment of 2 with aqueous sodium acetate has afforded the corresponding 3-phenyl-5-diazopyrazole (6). The latter reacted readily with dipolarophiles to yield pyrazolo- [1,5-c]-as-triazine derivatives. Pyrazolo[1,5-c]-as-triazines has also been formed upon treatment of 6 with active methylene compounds. The mechanism of reaction of 2 and 6 with active methylene compounds is discussed.Diazotization of 5-amino-3-ethyl-1,2,4-triazole nitrate (7) has afforded the corresponding diazonium derivative which coupled with benzoylacetonitrile and with acetoacetanilide to yield the corresponding hydrazones 9 a, b. The latter could be cyclised into 1,2,4-triazolo[1,5-c]-as-triazines by the action of concentrated sulphuric acid

scholarly journals Studies With Enamines: Synthesis and Reactivity of 4-Nitrophenyl-1-piperidinostyrene. Synthesis of Pyridazine, Oxadiazole, 1,2,3-Triazole and 4-Aminopyrazole Derivatives

2007 ◽  
Vol 62 (2) ◽  
pp. 261-266 ◽  
Author(s):  
Tayseer A. Abdallah ◽  
Abdellatif M. Salaheldin ◽  
Naglaa F. Radwan
Keyword(s):  
Diazonium Salt ◽  
Hydroxylamine Hydrochloride ◽  
Triazole Derivatives ◽  
Active Methylene Compounds ◽  
Pyridazine Derivatives ◽  
Active Methylene

4-Nitrophenyl-1-piperidinostyrene (4) reacts with an aromatic diazonium salt to afford the arylhydrazonal 6. The latter condenses with active methylene compounds to yield pyridazine derivatives, and with hydroxylamine hydrochloride to produce oxadiazole and 1,2,3-triazole derivatives. Compound 12 was reacted with chloroacetonitrile to afford 4-aminopyrazoles 15.

scholarly journals Synthesis of Biheterocycles Containing Indole Nucleus and Their Antibacterial Activity

2011 ◽  
Vol 4 (1) ◽  
pp. 273 ◽  
Author(s):  
S. Jain ◽  
B. N. Reddy ◽  
K. S. Rao
Keyword(s):  
Antibacterial Activity ◽  
Hydrazine Hydrate ◽  
Ethyl Cyanoacetate ◽  
Active Methylene Compounds ◽  
New Compounds ◽  
Active Methylene

Indole-3-carboxaldehydes (1a-d) undergo condensation with ethyl cyanoacetate and malononitrile to give the acrylonitrile 2a-d and 3a-d which on reaction with hydrazine hydrate yield 3,5-diamino-5-hydroxy-4-(3-indolylmethylene)pyrazoles (4a-d) and 3-amino-5-hydroxy -4-(3-indolylmethylene)pyrazoles (5a-d), respectively. The new compounds were also screened for their antibacterial activity.Keywords:  Indole-3-carboxaldehydes ; Active methylene compounds; Base; Hydrazine hydrate;  Pyrazoles.© 2012 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi: http://dx.doi.org/10.3329/jsr.v4i1.7821 J. Sci. Res. 4 (1), 273-278 (2012)

Reactions with Cyclic Amidenes III: Synthesis of Some New Fused Pyrazole Derivatives

1979 ◽  
Vol 34 (2) ◽  
pp. 275-279 ◽  
Author(s):  
Mohamed Hilmy Elnagdi ◽  
Ezzat Mohamed Kandeel ◽  
Kamal Usef Sadek
Keyword(s):  
The Other ◽  
Pyrazole Derivatives ◽  
Triazine Derivative ◽  
Other Hand ◽  
Triazine Derivatives ◽  
Active Methylene

AbstractDiazotised 5-amino-3-hydroxy-4-phenylazopyrazole (1 a) and 3,5-diamino-4-phenylazo-pyrazole(1 b) coupled with active methylene reagents to yield the pyrazolo[1,5-c]-as-triazine derivatives (3a, b-5 a, b). On the other hand coupling of diazotised 1 a, with β-naphthal has afforded the acyclic azo derivative(6). Whereas diazotised 1 a underwent intramolecular cyclisation into the pyrazolo[1,5-c]-1,2,3,4-tetrazine derivative (3)on attemptet addition to acrylonitrile, diazotised 1 b reacted with acrylonitrile under the same conditions to yield the pyrazolo[1,5-c]-pyridazine derivative (4). Compounds 1 a, b reacted with benzoylisothiocyanate to yield the pyrazol-5-ylthiourea derivatives (10 a, b). Where as 10 a readily cyclised into the pyrazolo[3,4-c]-as-triazine derivative (11) on refluxing with pyridine, compound 10 b hydrolysed under the same conditions into the pyrazol-5-ylthiourea derivative (12).

Synthesis of Some Pyrazolopyridine Sulphonamide Derivatives

1991 ◽  
Vol 46 (4) ◽  
pp. 541-546 ◽  
Author(s):  
A. M. Kamal El-Dean ◽  
A. A. Atalla ◽  
Th. A. Mohamed ◽  
A. A. Geies
Keyword(s):  
Hydrazine Hydrate ◽  
Diazonium Salt ◽  
Alkyl Halides ◽  
Heterocyclic Amines

The diazonium salt of 3-aminopyrazolopyridine when treated with SO2 and CuCl2 produces the corresponding sulphonyl chloride. The sulphonyl chloride chloride easily reacts with hydrazine hydrate, ammonia, aromatic or heterocyclic amines to produce the corresponding sulphohydrazide, sulphonamide or N-sulphonamide derivatives. Sulphohydrazide reacts with acetylacetone to produce pyrazoly pyrazolopyridinyl sulphone which is also obtained by reaction of sulphonyl chloride with dimethylpyrazole. The aminopyrazolopyridine can be converte into pyrazolopyridinthiole by its reacting with ethyl dithioxanthate. The pyrazolopyridinthiole reacts with alkyl halides or acrylonitrile to produce S-alkylated derivatives.

scholarly journals Potassium Hydroxide Impregnated Alumina (KOH-Alumina) as a Recyclable Catalyst for the Solvent-Free Multicomponent Synthesis of Highly Functionalized Substituted Pyridazines and/or Substituted Pyridazin-3(2H)-ones under Microwave Irradiation

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Hormi Mecadon ◽  
Bekington Myrboh
Keyword(s):  
Microwave Irradiation ◽  
Hydrazine Hydrate ◽  
Potassium Hydroxide ◽  
Recyclable Catalyst ◽  
Solvent Free ◽  
Multicomponent Synthesis ◽  
One Pot ◽  
Rapid Access ◽  
Mw Irradiation ◽  
Active Methylene

The work described herein employs potassium hydroxide impregnated alumina (KOH-alumina) as a mild, efficient, and recyclable catalyst for a one-pot solvent-free and environmentally safer synthesis of 3,4,6-triarylpyridazines and some substituted pyridazines from active methylene carbonyl species, 1,2-dicarbonyls, and hydrazine hydrate by microwave (MW) irradiation. The method offers highly convergent, inexpensive, and functionality-tolerable procedure for rapid access to important pyridazine compounds in good yields.

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