1145-01-3Relevant articles and documents
Oxidative decarboxylation of benzilic acid by a biomimetic iron(II) Complex: Evidence for an iron(IV)-oxo-hydroxo oxidant from O2
Paria, Sayantan,Que Jr., Lawrence,Paine, Tapan Kanti
, p. 11129 - 11132 (2011)
O2-dependent transformation: An iron(II)-benzilate complex of a tridentate N3 donor ligand reacts with O2 to undergo oxidative decarboxylation. Cyclohexene is selectively converted into cis-cyclohexane-1,2- diol in the reaction. Copyright
A novel synthesis of 5-aryl-3-phenylpyrazole from 2-aryl-3-benzoyl-1,1- cyclopropanedicarbonitrile and hydrazine
Ren, Zhongjiao,Cao, Weiguo,Chen, Jie,Wang, Yu,Ding, Weiyu
, p. 495 - 497 (2006)
A new process for synthesis of 5-aryl-3-phenylpyrazole is achieved. The regioselective ring-opening reaction of 2-aryl-3-benzoyl-1,1- cyclopropanedicarbonitrile with hydrazine plays a crucial role in the described process.
A novel one-pot method for the preparation of pyrazoles by 1,3-dipolar cycloadditions of diazo compounds generated in situ
Aggarwal, Varinder K.,De Vicente, Javier,Bonnert, Roger V.
, p. 5381 - 5383 (2003)
A convenient one-pot procedure for the preparation of pyrazoles by 1,3-dipolar cycloaddition of diazo compounds generated in situ has been developed. Diazo compounds derived from aldehydes were reacted with terminal alkynes to furnish regioselectively 3,5-disubstituted pyrazoles. Furthermore, the reaction of N-vinylimidazole and diazo compounds derived from aldehydes gave exclusively 3-substituted pyrazoles in a one-pot process.
Hexacarbonylmolybdenum-Induced N-N Bond Cleavage of Pyrazoles. Conversion of 1-Acylpyrazoles to Pyrimidines
Nitta, Makoto,Hamamatsu, Tatsuo,Miyano, Hiroyuki
, p. 4473 - 4475 (1988)
-induced reactions of 1-acyl-3,5-disubstituted pyrazoles underwent N-N bond cleavage and subsequent cyclocondensation to give pyrimidines as well as deacylation to give 3,5-disubstituted pyrazoles.Under similar conditions, 1,3,5-trisubstituted pyrazoles, which have no electron-withdrawing substituent on N1, gave no product, except for the starting materials.
Electrooxidation of N-aminopyrazoles
Itoh,Nagata,Okada,Ohsawa
, p. 1524 - 1526 (1990)
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Ege
, p. 1665 (1963)
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Synthesis of [3,3′(4H,4′H)-Bi-2H-1,3-oxazine]-4,4′-diones and their hydrolysis
Korkusuz, Elif,Yildirim, Ismail
, p. 1339 - 1347 (2013)
The [3,3′(4H,4′H)-bi-2H-1,3-oxazine]-4,4′-diones 3a-3i were obtained by [2+4] cycloaddition reactions of furan-2,3-diones 1a-1c with aromatic aldazines 2a-2d (Scheme 1). So, new derivatives of bi-2H-1,3-oxazines and their hydrolysis products, 3,5-diaryl-1H-pyrazoles 4a-4c (Scheme 3), which are potential biologically active compounds, were synthesized for the first time. Copyright
A facile and convenient approach to the synthesis of 3,5-diaryl-1H- pyrazoles
Nikpour, Farzad,Beigvand, Mahdi
, p. 821 - 824 (2008)
A simple and convenient one-pot synthesis route is described for the synthesis of 3,5-diaryl-1H-pyrazoles in short reaction times from the reaction of α-epoxyketones with semicarbazide hydrochloride under mild conditions.
Monoamine oxidase isoform-dependent tautomeric influence in the recognition of 3,5-diaryl pyrazole inhibitors
Chimenti, Franco,Fioravanti, Rossella,Bolasco, Adriana,Manna, Fedele,Chimenti, Paola,Secci, Daniela,Befani, Olivia,Turini, Paola,Ortuso, Francesco,Alcaro, Stefano
, p. 425 - 428 (2007)
A series of 3,5-diaryl pyrazoles were prepared and assayed for their ability to inhibit reversibly monoamine oxidase-A (MAO-A) and monoamine oxidase B (MAO-B). Several compounds show inhibitory activity with concentration values in the nanomolar range. A computational work was carried out on the two most selective inhibitors that have tautomeric pyrazole forms. The binding free energies of these compounds for each MAO isoform were influenced by the tautomeric equilibria.
Metal-free cascade synthesis of unsymmetrical 2-aminopyrimidines from imidazolate enaminones
Cui, Xue,Li, Youbin,Ma, Jianting,Wang, Xuesong,Xu, Junyu,Zeng, Tingting
, p. 24247 - 24253 (2021)
A convenient metal-free synthesis of unsymmetrical 2-aminopyrimidines from imidazolate enaminones has been developed. In this procedure, various structural 2-aminopyrimidines, as well as 4,5-dihydroisoxazol-5-ols and pyrazoles were synthesized in moderate to excellent yields. A plausible mechanism was also proposed for the cascade reaction. This method represents an effective strategy towards the synthesis of unsymmetrical 2-aminopyrimidines.
New "green" approaches to the synthesis of pyrazole derivatives
Corradi, Anna,Leonelli, Cristina,Rizzuti, Antonino,Rosa, Roberto,Veronesi, Paolo,Grandi, Romano,Baldassari, Sara,Villa, Carla
, p. 1482 - 1495 (2007)
A novel approach to the synthesis of pyrazole derivatives from tosylhydrazones of α,β-unsaturated carbonyl compounds possessing a β-hydrogen is proposed, exploiting microwave (MW) activation coupled with solvent free reaction conditions. The cycloaddition was studied on three ketones (trans-4-phenyl-3-buten-2-one, β-ionone and trans-chalcone). The corresponding 3,5-disubstitued-1H-pyrazoles were obtained in high yields and after short reaction times. In order to simplify and point out the green chemistry features of the method, a further improvement was achieved under the same catalytic conditions with a "one pot" synthesis of these heterocyclic compounds, starting directly from their carbonyl precursors via tosylhydrazones generated in situ. For an exhaustive study, the dielectric properties of the solid reaction mixtures were also measured, in order to obtain input data for the numerical simulation of their heating behaviour in the single mode MW cavity which was used for experimental work. In order to supply a valid methodology and tool for measuring the environmental impact, a comparative study between the synthetic route proposed and the classical synthetic route has been carried out.
Synthesis of zirconia doped molybdenum oxide as efficient catalysts for ultrasound assisted synthesis of substituted pyrazoles
MUFTAH, AMAL A.,WAGHMODE, SHOBHA A.,GADALE, SHARDA R.
, p. 2007 - 2014 (2021/08/24)
To explore green methodology for the synthesis of mixed oxide, its catalytic activity and temperature stability of series of ZrO2/MoO3 and ZrO2 were prepared by sol-gel method and characterized by XRD, FT-IR, X-ray photoelectron spectroscopy (XPS), temperature programmed Desorption (TPD), Raman spectroscopy and transmission electron microscopes (TEM). These mixed oxides were showed high stability with nanocrystalline nature. Due to highly acidic nature of the catalysts, ultra sound assisted synthesis of substituted pyrazoles was carried out successfully with high yield. The reaction was carried out in solvent free medium, which showed green approach and energy saving reaction. Condensation of dibenzoyl methane and hydrazine to form substituted pyrazoles with 97.7% yield. The acid strength and acid amount of synthesized catalysts were determined by temperature programmed desoprtion (TPD), incorporation of zirconia into the molybdenum, network has changed its surface acid properties due to the Zr2+ and Mo6+ ions. After addition of ZrO2 on MoO3, it showed weak and strong acid sites.
Discovery of pyrazole N-aryl sulfonate: A novel and highly potent cyclooxygenase-2 (COX-2) selective inhibitors
Guo, Quanping,Wang, Mengran,Wang, Rui,Xu, Zhaoqing,Yao, Haiyan
, (2021/08/25)
Based on a new pyrazole sulfonate synthetic method, a novel class of molecules with a basic structure of pyrazole N-aryl sulfonate have been designed and synthesized. The interest in conducting intensive research stems from quite evident anti-inflammatory effects exhibited by the compounds in preliminary animal experiments. A series of compounds were synthesized by different substitutions of the R1, R2, and R3 groups. Within the series, 4-iodophenyl 5-methyl-3-(p-tolyl)-1H-pyrazole-1-sulfonate and phenyl 5-methyl-3-(4-(trifluoromethyl) phenyl)-1H-pyrazole-1-sulfonate exhibited excellent anti-inflammatory activity (% inhibition of auricular edemas = 27.0 and 35.9, respectively); the in vivo analgesic activity of phenyl 5-methyl-3-(p-tolyl)-1H-pyrazole-1-sulfonate and 2-chlorophenyl 5-methyl-3-(p-tolyl)-1H-pyrazole-1-sulfonate was confirmed to be effective (inhibition ratio of writhing = 50.7% and 48.5% separately), and compounds phenyl 5-methyl-3-(p-tolyl)-1H-pyrazole-1-sulfonate, 4-iodophenyl 5-methyl-3-(p-tolyl)-1H-pyrazole-1-sulfonate and 2-chlorophenyl 5-methyl-3-(p-tolyl)-1H-pyrazole-1-sulfonate were identified as selective COX-2 inhibitors (SI = 455, 10,497 and >189 severally). In Acute Oral Toxicity assays conducted in vivo, the lethal dose 50 (LD50) of 4-iodophenyl 5-methyl-3-(p-tolyl)-1H-pyrazole-1-sulfonate and 2-chlorophenyl 5-methyl-3-(p-tolyl)-1H-pyrazole-1-sulfonate to mice was >2000 mg/kg BW.
