87119-67-3Relevant articles and documents
A one-pot process for the microwave-assisted synthesis of 7-substituted pyrazolo[1,5-a]pyrimidine
Bassoude, Ibtissam,Tber, Zahira,Essassi, El Mokhtar,Guillaumet, Gérald,Berteina-Raboin, Sabine
, p. 3301 - 3306 (2016/01/15)
An efficient synthesis of 7-substituted pyrazolo[1,5-a]pyrimidines using a one-pot, two-step process via Pd-catalyzed direct CH-arylation followed by a saponification-decarboxylation reaction is reported. Compared to the classical method (Negishi coupling), this new procedure has the advantages of convenient manipulation, short reaction times, excellent yields and the use of commercially available and relatively non-toxic compounds.
Reaction of pyran-2-one with 5-amino-1H-pyrazoles: Synthesis and characterization of 5,7-dimethylpyrazolo[1,5-a] pyrimidines and their regioisomeric ethyl esters
Aggarwal, Ranjana,Rani, Chinu,Kumar, Rajiv
, p. 419 - 428 (2019/01/21)
In this work, the reaction of 4-hydroxy-6-methylpyran-2-one, a bifunctional compound, with various 5-amino-3/4-aryl-1H-pyrazoles in ethanol has been studied. While the reaction with 5-amino-3-aryl-1H-pyrazoles affords three products namely 5,7-dimethylpyrazolo[1,5-a]pyrimidines 3, ethyl 2-(7-methylpyrazolo [1,5-a]pyrimidin- 5-yl)acetates 4 and its regioisomer ethyl 2-(5-methylpyrazolo[1,5-a]pyrimidin-7- yl)acetates 5, 5-amino-4-aryl-1H-pyrazoles led to the formation of two products 5,7- dimethylpyrazolo[1,5-a] pyrimidines 7 and ethyl 2-(5-methylpyrazolo[1,5-a]pyrimidin- 7-yl)acetates 8. The products were characterized unambiguously by rigorous analysis of IR, NMR (1H and 13C) and mass spectrometry and a mechanism is proposed for their formation.
Catalyst- and base-controlled site-selective sp2 and sp 3 direct arylation of 5,7-dimethyl-2-phenylpyrazolo[1,5-a]pyrimidine using aryl bromides
Bassoude, Ibtissam,Berteina-Raboin, Sabine,Massip, Stephane,Leger, Jean-Michel,Jarry, Christian,Essassi, El Mokhtar,Guillaumet, Gerald
experimental part, p. 2572 - 2578 (2012/06/01)
The palladium-catalyzed direct C-H arylation of various heterocyclic is now recognized to be the most effective methodology for making aromatic compounds. In this paper, we present a new approach to control the site-selective direct C-H arylation of both
One-step reaction leading to new pyrazolo[1,5-a]pyrimidines by condensation of 2-pyrone with 5(3)-amino-3(5)-arylpyrazoles
Bassoude, Ibtissam,Berteina-Raboin, Sabine,Leger, Jean-Michel,Jarry, Christian,Essassi, El Mokhtar,Guillaumet, Gérald
experimental part, p. 2279 - 2286 (2011/04/22)
Condensation of 5(3)-amino-3(5)-arylpyrazoles with 4-hydroxy-6-methylpyran- 2-one leads to 5,7-dimethyl-2-arylpyrazolo[1,5-a]pyrimidines, 5-alkoxycarbonylmethyl-7-methyl-2-arylpyrazolo[1,5-a]pyrimidines and their isomeric 7-alkoxycarbonylmethyl-5-methyl-2
Facile synthesis of fluorinated 2-aryl-5,7 bisalkyl pyrazolo pyrimidines from arylalkyne nitriles
Rama Rao,Lingaiah,Ezikiel,Yadla,Shanthan Rao
, p. 275 - 280 (2007/10/03)
Synthesis of pyrazolopyrimidines from fluorine substituted arylalkynenitriles is described. Arylalkynenitriles 1a-d reacted with hydrazine to give 5-aryl-3-amino-2H-pyrazoles 2a-d. The condensation of aminopyrazoles with 1,3-dicarbonyl compounds furnished
Pyrazolopyrimidines based on 5-aminopyrazoles unsubstituted at the position 1
Nam,Grandberg,Sorokin
, p. 1371 - 1374 (2007/10/03)
By condensation of various symmetric β-diketones with a series of 5-aminopyrazoles that are unsubstituted at the position 1, we have obtained a series of pyrazolo[1,5-a]pyrimidines that are of interest as physiologically active compounds. Hexafluoroacetylacetone reacts in another direction, forming pyrazolo[4,5-b]pyridine.
Synthesis of N-alkylated derivatives of pyrazolo[1,5-a]-pyrimidine and their reaction with methylamine
Danagulyan,Panosyan,Boyakhchyan
, p. 581 - 585 (2007/10/03)
With the object of studying the factors influencing the course of enamine rearrangements, we have carried out the N-alkylation of alkyl- and aryl-substituted pyrazolo[1,5-a]pyrimidines. Using the NOEDIF NMR spectroscopic method for the cases of 5,7-dimeth
α-Aminoazoles in the synthesis of heterocycles: I. Synthesis of regioisomeric 5-methyl-2,7-diphenyl-and 7-methyl-2,5-diphenylpyrazolo[1,5-a]pyrimidines
Petrov,Emelina,Firsov
, p. 1027 - 1032 (2007/10/03)
4-Phenyl-3-butyn-2-one reacts with 3(5)-amino-5(3)-phenylpyrazole on heating in DMSO to give 7-methyl-2,5-diphenylpyrazolo[1,5-a]pyrimidine. The reaction of 3(5)-amino-5(3)-phenylpyrazole with benzoylacetone in chloroform, ethanol, and DMSO results in formation of a mixture of isomeric pyrazolopyrimidines, the major product being 5-methyl-2,7-diphenylpyrazolo[1,5-a]pyrimidine.
New anti-inflammatory/anti-arthritic heterocyclic bisphosphonates
Nugent, Richard A.,Dunn, Colin J.,Staite, Nigel D.,Murphy, Michael J.,Schlachter, Stephen T.,Aspar, Danielle G.,Shields, Sharon K.,Galinet, Louise A.
, p. 229 - 232 (2007/10/03)
In the course of research toward a safe and effective treatment for rheumatoid arthritis, we identified new pyrazolo[1,5-a]pyrimidine and 4-pyrimidinone bisphosphonate esters, which are potent inhibitors of a murine model of chronic, cutaneous inflammatio
Chemical and Electrochemical Reduction of some Pyrazolopyrimidines
Bellec, Christian,Lhommet, Gerard
, p. 1793 - 1800 (2007/10/03)
Various pyrazolopyrimidines 1 are prepared by two different ways.Their chemical reduction by sodium borohydride leads generally to 4,5,6,7-tetrahydro compounds 3, while lithium aluminum hydride yields 4,7-dihydro derivatives 2 at room temperature, and 3 in refluxing tetrahydrofuran.A complex mixture of oxidizable hydrodimers is obtained by electrochemical reduction.An electroreduction at a more negative potential also gives 4,7-dihydro compounds 2.A new 4,5-dihydropyrazolopyrimidine has been obtained by condensation of 5-amino-3-methyl-1H-pyrazole with acetophenone.
