Relevant bibliographies by topics / Pyrazole-4

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Academic literature on the topic 'Pyrazole-4'

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Published: 6 September 2023

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Journal articles on the topic "Pyrazole-4"

1

Abaszadeh, Mehdi, Hassan Sheibani, and Kazem Saidi. "The Condensation of (Chlorocarbonyl)phenyl Ketene with Bisnucleophiles. Synthesis of 4-Hydroxy-5-phenylpyro-[2,3-c]pyrazol-6-ones and Formation of Pyrazolo[1,2-a]pyrazole-triones by Hydrogen Exchange in Unstable Mesoionic Compounds." Australian Journal of Chemistry 63, no. 1 (2010): 92. http://dx.doi.org/10.1071/ch09344.

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The addition of (chlorocarbonyl)phenyl ketene 2 to 5-alkylpyrazol-3(4H)-ones 1 led to the formation of 3-hydroxypyrazolo[1,2-a]pyrazole-dione/pyrazolo[1,2-a]pyrazole-trione derivatives 3. This is ascribed to hydrogen exchange in initially formed unstable, mesoionic pyrazolo[1,2-a]pyrazol-4-ium-5-olates. In contrast, condensation of the same ketene with 3-alkyl-1-phenyl-2-pyrazolin-5-ones 4 afforded 4-hydroxy-3-alkyl-1,5-diphenylpyrano[2,3-c]pyrazol-6-one derivatives 5. The latter reaction provides a new and rapid route to 4-hydroxy-2-pyrones fused to pyrazole rings, in good to excellent yields.
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2

Hartwig de Oliveira, Daniela, Fernanda Severo Sabedra Sousa, Paloma Taborda Birmann, Ana Paula Pesarico, Diego Alves, Raquel Guimarães Jacob, and Lucielli Savegnago. "Evaluation of antioxidant activity and toxicity of sulfur- or selenium-containing 4-(arylchalcogenyl)-1H-pyrazoles." Canadian Journal of Physiology and Pharmacology 98, no. 7 (July 2020): 441–48. http://dx.doi.org/10.1139/cjpp-2019-0356.

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Pyrazoles represent a significant class of heterocyclic compounds that exhibit pharmacological properties. The present study aimed to investigate the antioxidant potential of pyrazol derivative compounds in brain of mice in vitro and the effect of pyrazol derivative compounds in the oxidative damage and toxicity parameters in mouse brain and plasma of mice. The compounds tested were 3,5-dimethyl-1-phenyl-4-(phenylselanyl)-1H-pyrazol (1a), 3,5-dimethyl-4-(phenylselanyl)-1H-pyrazole (2a), 4-((4-methoxyphenyl)selanyl)-3,5-dimethyl-1-phenyl-1H-pyrazole (3a), 4-((4-chlorophenyl)selanyl)-3,5-dimethyl-1-phenyl-1H-pyrazole (4a), 3,5-dimethyl-1-phenyl-4-(phenylthio)-1H-pyrazole (1b), 3,5-dimethyl-4-(phenylthio)-1H-pyrazole (2b), 4-((4-methoxyphenyl)thio)-3,5-dimethyl-1-phenyl-1H-pyrazole (3b), 4-((4-chlorophenyl)thio)-3,5-dimethyl-1-phenyl-1H-pyrazole (4b), and 3,5-dimethyl-1-phenyl-1H-pyrazole (1c). In vitro, 4-(arylcalcogenyl)-1H-pyrazoles, at low molecular range, reduced lipid peroxidation and reactive species in mouse brain homogenates. The compounds also presented ferric-reducing ability as well nitric oxide-scavenging activity. Especially compounds 1a, 1b, and 1c presented efficiency to 1,1-diphenyl-2-picryl-hydrazyl-scavenging activity. Compounds 1b and 1c presented 2,20 -azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)-scavenging activity. In vivo assays demonstrated that compounds 1a, 1b, and 1c (300 mg/kg, intragastric, a single administration) did not cause alteration in the of δ-aminolevulinic acid dehydratase activity, an enzyme that exhibits high sensibility to prooxidants situations, in the brain, liver, and kidney of mice. Compound 1c reduced per se the lipid peroxidation in liver and brain of mice. Toxicological assays demonstrate that compounds 1a, 1b, and 1c did not present toxicity in the aspartate aminotransferase, alanine aminotransferase, urea, and creatinine levels in the plasma. In conclusion, the results demonstrated the antioxidant action of pyrazol derivative compounds in in vitro assays. Furthermore, the results showed low toxicity of compounds in in vivo assays.
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3

Alsayari, Abdulrhman, Abdullatif Bin Muhsinah, Yahya I. Asiri, Jaber Abdullah Alshehri, Yahia N. Mabkhot, Mohammad Y. Alfaifi, Serag Eldin I. Elbehairi, Mater H. Mahnashi, and Mohd Zaheen Hassan. "Arylhydrazono/Aryldiazenyl Pyrazoles: Green One-Pot Solvent-Free Synthesis and Anticancer Evaluation." Letters in Organic Chemistry 17, no. 10 (November 17, 2020): 772–78. http://dx.doi.org/10.2174/1570178617666200320104923.

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The aim of this study was to synthesize and evaluate the biological activity of pyrazole derivatives, in particular, to perform a “greener” one-pot synthesis using a solvent-free method as an alternative strategy for synthesizing hydrazono/diazenyl-pyridine-pyrazole hybrid molecules with potential anticancer activity. Effective treatment for all types of cancers is still a long way in the future due to the severe adverse drug reactions and drug resistance associated with current drugs. Therefore, there is a pressing need to develop safer and more effective anticancer agents. In this context, some hybrid analogues containing the bioactive pharmacophores viz. pyrazole, pyridine, and diazo scaffolds were synthesized by one-pot method. Herein, we describe the expedient synthesis of pyrazoles by a onepot three-component condensation of ethyl acetoacetate/acetylacetone, isoniazid, and arenediazonium salts under solvent-free conditions, and the evaluation of their cytotoxicity using a sulforhodamine B assay on three cancer cell lines. Molecular docking studies employing tyrosine kinase were also carried out to evaluate the binding mode of the pyrazole derivatives under study. 1-(4-Pyridinylcarbonyl)-3- methyl-4-(2-arylhydrazono)-2-pyrazolin-5-ones and [4-(2-aryldiazenyl)-3,5-dimethyl-1H-pyrazol-1- yl]-4-pyridinylmethanones, previously described, were prepared using an improved procedure. Among these ten products, 1-isonicotinoyl-3-methyl-4-[2-(4-nitrophenyl)hydrazono]-2-pyrazolin-5-one (1f) displayed promising anticancer activity against the MCF-7, HepG2 and HCT-116 cell lines, with an IC50 value in the range of 0.2-3.4 μM. In summary, our findings suggest that pyrazoles containing hydrazono/ diazenyl and pyridine pharmacophores constitute promising scaffolds for the development of new anticancer agents.
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Andicsová, Anita, Angelika Lásiková, Marek Fronc, Jozef Kožíšek, and Daniel Végh. "3-(2-Heteroaryl)-pyrazolotetrazoles – a subunits for losartan-like structures." Acta Chimica Slovaca 5, no. 2 (November 1, 2012): 220–24. http://dx.doi.org/10.2478/v10188-012-0033-z.

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Abstract A modification of biphenylyltetrazole moiety of Losartan (A) by 3-(2-heteroaryl)-pyrazolotetrazole (B) is described. Ketone semicarbazones react with two moles of phosphorus oxychloride-dimethylformamide with the formation of 3-substituted pyrazol-4-carbaldehydes. The transformations of 3-substituted pyrazole-4- carboxaldehydes to 3-substituted pyrazole-4-nitriles were carried out by reaction of hydroxylamine in DMFA. The prepared cyano pyrazoles were converted to tetrazoles by heating with trimethylsilylazide and dibuthyltinoxide in toluene.
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Srinivasa Reddy, T., Hitesh Kulhari, V. Ganga Reddy, A. V. Subba Rao, Vipul Bansal, Ahmed Kamal, and Ravi Shukla. "Synthesis and biological evaluation of pyrazolo–triazole hybrids as cytotoxic and apoptosis inducing agents." Organic & Biomolecular Chemistry 13, no. 40 (2015): 10136–49. http://dx.doi.org/10.1039/c5ob00842e.

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A series of pyrazolo–triazole hybrids were designed and synthesized by combining the 1,3-diphenyl pyrazole and triazole scaffolds to obtain (1-benzyl-1H-1,2,3-triazol-4-yl)(1,3-diphenyl-1H-pyrazol-4-yl)methanones.
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Lindsay-Scott, Peter J., and Eloise Rivlin-Derrick. "Regiocontrolled Synthesis of 6,7-Dihydro-4H-pyrazolo[5,1-c][1,4]oxazines." Synthesis 52, no. 01 (October 8, 2019): 105–18. http://dx.doi.org/10.1055/s-0037-1610734.

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Synthetic access to 6,7-dihydro-4H-pyrazolo[5,1-c][1,4]oxazines has been achieved in 3–4 steps from commercially available pyrazoles. Optimization of a protected hydroxyethyl group on N1 enabled the regiocontrolled construction of pyrazole-5-aldehydes in high yields; subsequent deprotection and reduction generated fused heterocyclic scaffolds bearing multiple substitution patterns. Moreover, the intermediate pyrazole lactols were shown to be versatile synthetic building blocks.
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Ramadan, El Sayed, Essam M. Sharshira, Ramadan I. El Sokkary, and Noussa Morsy. "Synthesis and antimicrobial evaluation of some heterocyclic compounds from 3-aryl-1-phenyl-1H-pyrazole-4-carbaldehydes." Zeitschrift für Naturforschung B 73, no. 6 (June 27, 2018): 389–97. http://dx.doi.org/10.1515/znb-2018-0009.

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AbstractA new series of chalcones, pyrazolinyl-pyrazoles, pyrazole-4-carbaldehyde oximes, pyrazole-4-carbonitriles, 5-pyrazolyl-1,2,4-triazolidine-3-thiones, and Knoevenagel condensation products was synthesized from 3-aryl-1-phenyl-1H-pyrazole-4-carbaldehydes. Most reactions were carried out either without solvent or in the presence of water as a green solvent. The structure of synthesized compounds was characterized by spectral and elemental analysis. The synthesized compounds were tested in vitro for their antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans in comparison with imipenem (intravenous β-lactam antibiotic) and clotrimazole (antifungal medication) as reference drugs by using the agar diffusion technique. 3-Aryl-1-phenyl-1H-pyrazole-4-carbonitriles 8b, 8c, and 8d showed significant antifungal activity against the fungus C. albicans.
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Deacon, Glen B., Peter C. Junk, and Aron Urbatsch. "Lanthanoid and Alkaline Earth Complexes Involving New Substituted Pyrazolates." Australian Journal of Chemistry 65, no. 7 (2012): 802. http://dx.doi.org/10.1071/ch12069.

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From the pyrazoles 3,5-di-(2′-furanyl)pyrazole (fu2pzH), 3-phenyl-5-(2′-thienyl)pyrazole (PhtpzH) and 3-(2′-furanyl)-5-(2′′-naphthyl)pyrazole (funappzH), a range of alkaline earth and lanthanoid pyrazolate complexes has been prepared by redox transmetallation/protolysis reactions between free metals, Hg(C6F5)2 and the pyrazoles, by reaction of I2‐activated metals with the pyrazoles, and in one case by a similar reaction of unactivated metal, in the donor solvents tetrahydrofuran (thf) and 1,2-dimethoxyethane (dme). Thus the divalent [Ca(Phtpz)2(thf)4], [Ba(Phtpz)2(thf)4] and [Ca(funappz)2(thf)4]·(thf) complexes, the heteroleptic [Yb(Phtpz)I(thf)4] and the trivalent [La(fu2pz)3(thf)3]·2thf complex have been prepared and structurally characterized, as well as the dme complexes [Yb(Phtpz)2(dme)2] and [Eu(Phtpz)3(dme)2]. Highlights include the first trans-[LnII(pz)I(thf)4] complex, a rare transoid [Ln(pz)2(dme)2] complex and a complex with both chelating and unidentate dme. In all cases, the Phtpz complexes exhibit pronounced positional disorder of the 2-thienyl and phenyl groups in the solid state, as do the two polymorphs of the parent pyrazole.
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Lam, Linh, Sang H. Park, and Joseph Sloop. "Synthesis and Characterization of 3-Methyl-1-(4-(trifluoromethyl)phenyl)indeno [1,2-c]pyrazol-4(1H)-one." Molbank 2022, no. 4 (November 7, 2022): M1483. http://dx.doi.org/10.3390/m1483.

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Pyrazoles have potential applications in the agrochemical and medicinal chemistry industries as pesticides, anti-inflammatory medications, and antitumor drugs. Fluorinated fused-ring pyrazoles may also possess medicinally useful properties. Herein, we report the acid-catalyzed synthesis of a new tricyclic, trifluoromethylated indenopyrazole, 3-methyl-1-(4-(trifluoromethyl)phenyl)indeno[1,2-c]pyrazol-4(1H)-one, from 2-acetyl-1,3-indanedione and 4-trifluoromethylphenylhydrazine. This isomeric pyrazole was obtained in yields ranging from 4–24%. NMR spectroscopic characterization and elemental analysis support the structural assignment, identity, and purity of the product.
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Rizk, Sameh, Ismail M. Awheda, and Fathi A. Smida. "Synthesis and DFT Study of Newly Schiff Base and Fused Heterocyclic Compounds as Antibacterial Agent." JOURNAL OF ADVANCES IN CHEMISTRY 16 (November 7, 2019): 5395–403. http://dx.doi.org/10.24297/jac.v16i0.8499.

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Treatment of 2,3-di-(4-chlorophenyl) oxirane-2,3-dicarbonitriles(1) with nitrogen nucleophiles, e.g. N2H4, NH2OH afforded pyrazole 2, 1.2oxazole 3 derivatives respectively The 3-amino pyrazole-4-one derivatives 2 can be used as a key starting materials to synthesize some important Schiff base 4 and fused heterocyclic compounds e.g. Imidazolo-[4,5-c]pyrazole 5, Pyrazolo[3,4-e]1,2,4-triazine 6, pyrazol[1,2-a] 1,3,5-triazine 7, 8 and 9. The electromeric effect of the halogen atom in the aryl moieties can be controlled upon the rate of reaction and the yield of the product. The structures of synthesized new compounds were characterized by spectral data and screened for their antimicrobial activities against various bacteria and fungi strains. The heterocyclic compounds 7, 8 and 9 that contained bridgehead nitrogen gave an excellent result.
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Dissertations / Theses on the topic "Pyrazole-4"

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Karahan, Dag Fulya. "Synthesis Of 5-ferrocenyl-4-((4-nitrophenyl)sulfenyl)-1h-pyrazoles By Electrophilic Cyclization." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613443/index.pdf.

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Pyrazoles have been intensely studied in the design and synthesis of biologically active agents because they display considerable medicinal activities. Recent studies have shown that integration of a ferrocenyl unit with structural features of pyrazoles can result in the formation of the new products with enhanced or/and unexpected biological activity since several ferrocene derivatives have already been illustrated to be active against a number of tumors. Therefore, we have investigated the electrophilic cyclizations of the hydrazones to afford 5-ferrocenyl-4-((4-nitrophenyl)sulfenyl)-substituted pyrazole derivatives. First, the requisite hydrazone derivatives were synthesized by the reactions of ferrocenyl propargyl aldehydes or ketones with a series of hydrazines. Then electrophilic cyclizations of these hydrazones were investigated by treating with 4-(nitrophenyl)sulfenyl chloride as electrophile. By employing these electrophilic cyclizations, a series of 5-ferrocenyl-4-((4-nitrophenyl)sulfenyl)-1H-pyrazoles, 5-ferrocenyl-4-((4-nitrophenyl) sulfenyl)-3-methyl-1H-pyrazoles and 5-ferrocenyl-4-((4-nitrophenyl)sulfenyl)-3-phenyl-1H-pyrazoles have been synthesized in moderate to good yields.
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2

Demirci, Deniz. "Synthesis Of 4-phenylselenyl-1h-pyrazoles By Electrophilic Cyclization." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613910/index.pdf.

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In this study, the synthesis of 5-ferrocenyl/aryl-4-(phenylselenyl)-1H-pyrazole derivatives was investigated since the integration of ferrocenyl and selenium moieties into pyrazole derivatives may increase their current biological activities. Initially, the starting propargyl aldehydes were synthesized from corresponding acetylenes. Subsequently, propargyl aldehydes were reacted with hydrazines to yield corresponding hydrazones. Then the in situ synthesized hydrazones were subjected to electrophilic cyclization with phenylselenyl chloride, which afforded 5-ferrocenyl/aryl-4-(phenylselenyl)-1H-pyrazoles in one-pot manner. Subsequently, reaction conditions were optimized in terms of electrophile, base, temperature and solvent. Best results were obtained with phenylselenyl chloride and NaHCO3 at room temperature in DCM for ferrocenyl substituted pyrazoles and DCE for aryl substituted pyrazoles. In summary, by employing the electrophilic cyclizations of in situ synthesized acetylenic hydrazones, a variety of 5-ferrocenyl/aryl-4-(phenylselenyl)-1H-pyrazole derivatives were synthesized in one-pot way in moderate to good yields.
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Barus, M. M. "А new approach to the preparation of 4-difluoromethyl-1Н-pyrazole-3-carboxylic acids." Thesis, БДМУ, 2022. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/19532.

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4

Yazici, Ceyda. "Synthesis Of 4-iodopyrazole Derivatives." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/3/12609750/index.pdf.

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Pyrazoles have been studied for over a century as an important class of heterocyclic compounds and continue to attract considerable interest due to the broad range of biological activities they possess. The electrophilic cyclization of the acetylenic hydrazones initiated by molecular iodine could provide new ways of synthesizing biologically active 4-iodopyrazole derivatives, which are important precursors for the synthesis of highly substituted pyrazole derivatives. For this reason, we investigated the synthesis of 4-iodopyrazole derivatives, such as 1-aryl- 5-alkyl/aryl-4-iodopyrazoles, starting from phenylhydrazine and ,-acetylenic aldehyde derivatives. Initially, ,-acetylenic aldehydes were synthesized by formylation reaction of corresponding alkynes with DMF. Then, hydrazone derivatives of these aldehydes were prepared by heating them with phenylhydrazine in a neat manner at 55 °
C for 5 h. Finally, acetylenic phenyl hydrazone derivatives were subjected to electrophilic cyclization by treating with excess molecular iodine at 80 °
C for 3 h. Although electrophilic cyclization is commonly used in organic chemistry, it has not been employed for the cyclization of acetylenic phenyl hydrazones to pyrazole derivatives. Under optimized conditions, these reactions afforded 1-aryl-5-alkyl/aryl-4-iodopyrazole derivatives in moderate to good yields as the single or the major product of the reactions. In some cases, 1-aryl-5-alkyl/arylpyrazole derivatives resulted from these reactions as minor products. In conclusion, 4-iodopyrazole derivatives were synthesized for the first time directly from acyclic starting materials, ,-acetylenic phenylhydrazones and iodine, via electrophilic cyclization.
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Cottineau, Bertrand. "Contribution à l'étude du 3-hydroxy-1H-pyrazole-4-carboxylate d'éthyle : application à la synthèse de composés antidiabétiques." Orléans, 2002. http://www.theses.fr/2002ORLE2014.

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Le diabète est l'affection endocrinienne de loin la plus fréquente. Il touche environ deux millions de personnes en France et se caractérise par une élévation de la concentration plasmatique en glucose et triglycérides. Cette hyperglycémie chronique contribue à l'apparition de complications spécifiques. Dans le cadre d'une recherche de nouveaux agents antidiabétiques, nous avons préparé à partir d'un synthon commun, le 3-hydroxy-1H-pyrazole-4-carboxylate d'éthyle, des composés diversement fonctionnalisés notamment en position 1 et 3 via des réactions de O et N-alkylations régiospécifiques, et en position 5 via des réactions de couplage catalysées au palladium (0). Par la suite, la mise au point des réactions de type ± Eenie-Meenie α à partir du (3-méthoxy-1-méthyl-1H-pyrazol-4-yl)-méthanol a permis la synthèse de 4-benzylpyrazoles. Les tests pharmacologiques, effectués par la société Merck-Santé, ont montré que certains composés synthétisés présentent une bonne activité hypoglycémiante.
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Kivrak, Arif. "Development Of New Methods For The Synthesis Of Pyrazoles, 4-iodopyrazoles, Isoxazoles And 1,2,4-oxadiazoles." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12612945/index.pdf.

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Synthesis of five-membered heteroaromatic compounds such as pyrazoles, isoxazoles and 1,2,4-oxadiazoles are important for pharmaceutical industry and material science due to their applications. Although there are many methods to prepare such compounds, new variants continue to appear since they exhibit a wide range of biological and medicinal activities. In this thesis, new methods were developed for the synthesis of 4-iodopyrazoles, pyrazoles, isoxazoles, 1,2,4-oxadiazoles and/or 1,2,4-oxadiazepines. In the first part of the study, electrophilic cyclization of &alpha
,&beta
-alkynic hydrazones by molecular iodine and copper iodide were investigated as new ways for the synthesis of 4-iodopyrazoles and pyrazoles, respectively. Initially, &alpha
,&beta
-alkynic hydrazones were prepared by the reactions of propargyl aldehydes and ketones with hydrazines. Then &alpha
,&beta
-alkynic hydrazones were treated with molecular iodine in the presence of NaHCO3, which afforded 4-iodopyrazoles in good to excellent yields. Subsequently, the same reactions were carried out with CuI in the presence of NEt3, which furnished corresponding pyrazoles in good yields. Moreover, ferrocenyl-substituted 4-iodopyrazoles and pyrazole derivatives were synthesized from corresponding
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7

Toto, Patrick. "Contribution à l'étude du 1H-pyrazole-4-carboxylate d'éthyle et de ses dérivés : application à la synthèse de nouveaux hétérocycles polycondensés." Orléans, 2004. http://www.theses.fr/2004ORLE2001.

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Le Diabète est une affection due à une déficience des mécanismes de régulation de la glycémie, dont la fréquence a augmentée de façon régulière et significative au sein des pays riches occidentaux durant les trente dernières années. Les hypoglycémiants de synthèse sont employés dans le cadre du traitement du Diabète non insulino-dépendant. Afin de synthétiser de nouvelles molécules hypoglycémiantes, des méthodologies de fonctionnalisation du 1H-pyrazole-4-carboxylate d'éthyle ont été développées à partir des 3 et 5 aminopyrazole-4-carboxylate d'éthyle. Dans un premier temps les positions 3 et 5 ont été halogénées par diazotation ou substitution électrophile. Les halogénopyrazoles obtenus ont permit d'accéder à divers pyrazoles tétrasubstitués par métallation, couplage ou SNar. Dans un deuxième temps des pontages N1-C5, C3-C4, C4-C5 ont conduit à de nouveaux hétérocycles polycondensés tel que les thiéno[2,3c]pyrazoles ou les 4-thia-1,8a-diaza-azulènes obtenus par métathèse.
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Desalegn, Nebiyou. "Kinetic Studies Of The Thermolysis Of 3-Halogenated-4,5-Dihydro-3h-Pyrazoles." Digital Archive @ GSU, 2005. http://digitalarchive.gsu.edu/chemistry_theses/1.

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3-Chloro-4,4,5-trimethyl-3,5-diphenyl-4,5-dihydro-3H-pyrazole (3b) and 3-bromo-4,4,5-trimethyl-3,5-diphenyl-4,5-dihydro-3H-pyrazole (3c) were prepared for the thermolysis project. The thermal decompositions of 3b and 3c were monitored using 1H NMR spectroscopy. Plots of ln (% starting material) vs. time (sec) were linear for at least two half lives and the first order rate constants were determined over at least a 30o temperature range. The relative reactivity was found to be 3c > 3b. The activation parameters determined for the thermal decomposition of the pyrazoline at 150oC were found to be: for 3b &#;H‡ = 33 &#;1.0 kcal/mol, &#;S‡ = -2.4 &#; 0.07eu , k150 0 = 7.34 &#; 0.44 x 10 -5 s-1 ; for 3c &#;H‡ = 30&#;0.2 kcal/mol, &#;S‡ = -6.9 &#;0.03 eu, k150o = 42.3&#;0.7 x 10-5 s-1. Thermal decomposition of 3b both neat and in dibromobenzene (DBB) resulted in the formation of an intermediate 2,3-diphenyl-4-methyl-1,3-pentadiene (8) as a major product and minor isomers of 8. These intermediates then thermally decomposed to 1,1,3-trimethyl-2-phenyl-1H-indene (9) via an acid catalyzed process. In order to gain a mechanistic understanding (ionic vs. radical pathways) of the thermal decomposition of 3b, a product study was conducted in protic solvents. In methanol and ethanol, 3b underwent an ionic reaction (SN1-type) with the solvent to produce 3-methoxy/ethoxy-4,4,5-trimethyl-3,5-diphenyl-4,5-dihydro-3H-pyrazole (3/3d) in good yield. The reaction of 3b with refluxing protic solvents led to the development of new method for the synthesis of alkoxy-4,5-dihydro-3H-pyrazoles which is both safe and efficient.
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9

Piovesan, Luciana Almeida. "Síntese de novos heterociclos a partir do ácido levulínico." Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/4233.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The synthesis of new compounds alkyl 3-azolyl propanoate e alkyl 3-azolyl propanoic acid structurally analogues to gamma-aminobutiric acid (GABA) is reported. One more time using the acetal acylation method, now the acetal derivative of 4-oxopentanoic acid (levulinic acid), the methyl 4,4- dimethoxypentanoate, were obtained the precursors methyl 7,7,7-trifluoro[chloro]-4- methoxy-6-oxo-heptenoates, 1,3-dieletrophilic precursor with alcanoate substituent. Are presented efficient and regioespecific synthetic routes from reactions of cyclocondensation [3+2] among 1,3-dieletrofilic precursors with hydroxylamine and different hydrazines, until training isoxazoles and pyrazoles, functionalized with the side chain alkyl propanoate or propanoic acid. Simultaneously to the formation of heterocycles, were studied the hydrolysis reaction of trichloromethyl group and transesterification reaction of methyl propanoate, in the same reactional medium. All products are novel, presenting a good to excellent yields, high purity and the structures were assigned by 1H NMR, 13C NMR and mass spectrometry.
A síntese de novos compostos 3-azolil-propanoatos de alquila e 3-azolilácidos propanóicos, análogos estruturalmente ao ácido gama-aminobutírico (GABA) é relatada. Novamente aplicando o método de acilação de acetais, agora ao acetal derivado do ácido 4-oxopentanóico (ácido levulínico), o 4,4-dimetoxipentanoato de metila, foram obtidos os precursores 7,7,7-triflúor[cloro]-4-metoxi-6-oxo-heptenoatos de metila, precursores 1,3-dieletrofílicos com o substituinte alcanoato. São apresentadas rotas sintéticas eficientes e regioespecíficas a partir de reações de ciclocondensação [3+2] entre os precursores 1,3-dieletrofílicos, com hidroxilamina e hidrazinas diferentes, até a formação de isoxazóis e pirazóis, funcionalizados com a cadeia lateral propanoato de alquila ou ácido propanóico. Simultaneamente à formação dos heterociclos, foram estudadas as reações de hidrólise do grupamento triclorometila e hidrólise ou transesterificação do propanoato de metila, no mesmo meio de reação. Todos os produtos obtidos são inéditos, apresentando rendimentos de bons a excelentes e pureza alta e suas estruturas foram atribuídas por RMN1H e 13C e por espectrometria de massas.
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Oleksik, Laurence. "Methodology for the synthesis of 4 or 5-substituted-3-perfluoroalkyl pyrazoles." Thesis, University of Leicester, 2004. http://hdl.handle.net/2381/30087.

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Initially the perfluoroacylation of a range of commercially available vinyl ethers and conversion of the resulting perfluoroacylated enol ethers to 1-H-pyrazoles via reaction with hydrazine is reported. The selective synthesis of a range of alpha-aryl vinyl ethers using Heck chemistry is then reported. Subsequent perfluoroacylations of the vinyl ethers followed by reaction of the resulting perfluoroacyl enol ethers with hydrazine affords a range of 5-aryl-3-perfluoroalkyl pyrazoles in good yields.;Alternative methodology for the synthesis of 5-aryl-3-perfluoroalkyl pyrazoles is then described in which resin bound esters are converted to vinyl ethers
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Book chapters on the topic "Pyrazole-4"

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Lynch, Michael P., James R. Beck, Eddie V. P. Tao, James Aikins, George E. Babbitt, John R. Rizzo, and T. William Waldrep. "1-Alkyl-5-cyano-1H-pyrazole-4-carboxamides." In ACS Symposium Series, 144–57. Washington, DC: American Chemical Society, 1991. http://dx.doi.org/10.1021/bk-1991-0443.ch012.

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Bährle-Rapp, Marina. "4,5-Diamino-1-((4-Chlorophenyl)Methyl)-1H-Pyrazole-Sulfate." In Springer Lexikon Kosmetik und Körperpflege, 151. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_2833.

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Lynch, Michael P., Stephen A. Ackmann, Dale R. Heim, George E. Davis, Michael A. Staszak, James R. Beck, Edward E. Tschabold, and Fred L. Wright. "Synthesis and Gametocidal Activity of 1-Aryl-5-(aminocarbonyl)-1H-pyrazole-4-carboxylic Acids." In Synthesis and Chemistry of Agrochemicals III, 200–211. Washington, DC: American Chemical Society, 1992. http://dx.doi.org/10.1021/bk-1992-0504.ch019.

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Shao, Xia, Keunsam Jang, and Peter J. H. Scott. "Synthesis of 1-(2,4-Dichlorophenyl)-4-Cyano-5-(4-[11C]methoxyphenyl)-N-(Piperidin-1-yl)-1H-Pyrazole-3-Carboxamide ([11C]OMAR)." In Radiochemical Syntheses, 73–80. Hoboken, NJ: John Wiley & Sons, Inc, 2015. http://dx.doi.org/10.1002/9781118834114.ch8.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of dinuclear bis(μ-3-pyridin-2yl-1, 2, 4-triazolato) copper(II) compound containing pyrazole as CO-ligand." In Magnetic Properties of Paramagnetic Compounds, 252–53. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-49202-4_115.

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Hamper, Bruce C., Kindrick L. Leschinsky, Deborah A. Mischke, and S. Douglas Prosch. "Chiral 3-Aryl-4-halo-5-(trifluoromethyl)pyrazoles." In ACS Symposium Series, 272–81. Washington, DC: American Chemical Society, 1999. http://dx.doi.org/10.1021/bk-2000-0746.ch019.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of μ3-OMe bridged tricopper(II) chloro complex with substituted pyrazole." In Magnetic Properties of Paramagnetic Compounds, Magnetic Susceptibility Data, Volume 4, 722–24. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-62474-6_291.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of μ3-OMe bridged tricopper(II) bromo complex with substituted pyrazole." In Magnetic Properties of Paramagnetic Compounds, Magnetic Susceptibility Data, Volume 4, 725–27. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-62474-6_292.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of cobalt(II) complex of 4-(sulfonylazido)phenylazo-pyrazolone." In Magnetic Properties of Paramagnetic Compounds, 943–44. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-53971-2_502.

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Pardasani, R. T., and P. Pardasani. "Magnetic properties of cobalt(II) complex of 4-(sulfonylazido)phenylazo-pyrazolone." In Magnetic Properties of Paramagnetic Compounds, 945–46. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-53971-2_503.

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Conference papers on the topic "Pyrazole-4"

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Hyuga, H., C. Goto, Y. Okazaki, A. Harada, S. Mitsumoto, K. Kamiyama, and S. Umegaki. "An Organic Crystal 3,5-dimethyl-1-(4-nitrophenyl)pyrazole for Compact Visible Light-sources." In Compact Blue-Green Lasers. Washington, D.C.: Optica Publishing Group, 1993. http://dx.doi.org/10.1364/cbgl.1993.cwa.2.

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The advent of blue-green IIVI semiconductor lasers is stimulating the research activity in more efficient frequency-conversions of III-V semiconductor-laser sources. In almost all cases of the conversions, inorganic materials are being used. On the other hand, organic materials have been developed and expected to give more efficiencies in the conversions because of their higher figures of merit in comparison with the inorganics.
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Prasad, T. N. Mahadeva, B. N. Lakshminarayana, Ebraheem Abdu Musad, M. A. Sridhar, K. M. Lokanath Rai, J. Shashidhara Prasad, Alka B. Garg, R. Mittal, and R. Mukhopadhyay. "Synthesis and X-ray Crystallographic Studies of ethyl 3-methyl5-(methylthio)-1H-pyrazole-4-carboxylate." In SOLID STATE PHYSICS, PROCEEDINGS OF THE 55TH DAE SOLID STATE PHYSICS SYMPOSIUM 2010. AIP, 2011. http://dx.doi.org/10.1063/1.3605798.

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Fauzi'ah, Lina, and Tutik Dwi Wahyuningsih. "Synthesis of 3-(4’-nitrophenyl)-4,5-dihydro pyrazole-based and its in-vitro antibacterial test." In PROCEEDING OF INTERNATIONAL CONFERENCE ON FRONTIERS OF SCIENCE AND TECHNOLOGY 2021. AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0103273.

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Chandra, N. Srikantamurthy, E. A. Jithesh Babu, K. B. Umesha, and M. Mahendra. "Synthesis and crystal structure studies of ethyl 5-methyl-1, 3-diphenyl-1H-pyrazole-4-carboxylate." In SOLID STATE PHYSICS: Proceedings of the 58th DAE Solid State Physics Symposium 2013. AIP Publishing LLC, 2014. http://dx.doi.org/10.1063/1.4872901.

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Medvedev, Michail, Michail Elinson, and Alexey Ilovaisky. "Green approach to the design of functionalized medicinally privileged 4-aryl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile scaffold !" In The 15th International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 2011. http://dx.doi.org/10.3390/ecsoc-15-00580.

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Mishra, Ashutosh, and Garima Jain. "XRD and xanes studies of copper complexes using (diethyl 4-amino-1-phenyl-1H-pyrazole-3,5 dicarboxylate) as ligand." In PROCEEDING OF INTERNATIONAL CONFERENCE ON RECENT TRENDS IN APPLIED PHYSICS AND MATERIAL SCIENCE: RAM 2013. AIP, 2013. http://dx.doi.org/10.1063/1.4810475.

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Koalla, Rajesh, Chandan Ghorui, Shivanand Mangali, Naveen Periketi, and A. K. Chaudhary. "Measurement of Refractive index and Absorption coefficient of 3, 4, 5 -Trinitro 1-H Pyrazole using Terahertz Time-domain Spectroscopy." In Frontiers in Optics. Washington, D.C.: OSA, 2021. http://dx.doi.org/10.1364/fio.2021.jw7a.58.

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Nikalje, Anna Pratima, Julio Seijas Vázquez, M. Pilar Vazquez-Tato, and Urja Nimbalkar. "Ionic liquid [Et3NH][HSO4]catalyslyzed multicomponent synthesis of 6 amino-4-(Substituted phenyl)-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile ." In The 20th International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 2016. http://dx.doi.org/10.3390/ecsoc-20-f011.

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Kumar, Rakesh, Neha Yadav, Jyoti Arora, and Ashok K. Prasad. "Synthesis of chiral 4-pyrazolyl dihydropyridines and their enantiomeric separation." In 15th Brazilian Meeting on Organic Synthesis. São Paulo: Editora Edgard Blücher, 2013. http://dx.doi.org/10.5151/chempro-15bmos-bmos2013_2013101521523.

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Jean Pierre, Bazureau, Camille Dago, Lou-Anna Voli, Thierry Roisnel, Christophe Brigaudeau, Yves-Alain Békro, Janat Mamybékova, and Olivier Mignen. "A Practical Access to New Pyrazole SKF-96365 Analogues as Potential Store-Operated Calcium Entry (SOCE) Inhibitors." In 4th International Electronic Conference on Medicinal Chemistry. Basel, Switzerland: MDPI, 2018. http://dx.doi.org/10.3390/ecmc-4-05618.

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Reports on the topic "Pyrazole-4"

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Schmidt, R. D., G. S. Lee, P. F. Pagoria, A. R. Mitchell, and R. Gilardi. Synthesis and Properties of a New Explosive, 4-Amino-3,5-Dinitro-lH-Pyrazole (LLM-116). Office of Scientific and Technical Information (OSTI), May 2001. http://dx.doi.org/10.2172/15005359.

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