pyrazoles-derivatives

Pyrazoles can be selectively lithiated at different carbons and subsequently react with electrophiles depending on the substitution patterns. 761446-44-0, formula is C10H17BN2O2, Name is 1-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole. 1-Methyl-5-(trifluoromethyl)pyrazole underwent deprotonation and subsequent carboxylation mainly or exclusively at either the 4-position of the heterocycle or at the nitrogen-attached methyl group. Related Products of 761446-44-0.

Gan, Linling;Gan, Zongjie;Dan, Yanrong;Li, Yaowei;Zhang, Peiming;Chen, Shanwen;Ye, Zaijun;Pan, Tao;Wan, Chunmei;Hu, Xuelian;Yu, Yu research published 《 Tetrazanbigen Derivatives as Peroxisome Proliferator-Activated Receptor Gamma (PPARγ) Partial Agonists: Design, Synthesis, Structure-Activity Relationship, and Anticancer Activities》, the research content is summarized as follows. Tetrazanbigen (TNBG) is a novel sterol isoquinoline derivative with poor water solubility and moderate inhibitory effects on human cancer cell lines via lipoapoptosis induction. Herein, we developed a series of novel TNBG analogs with improved water solubility and antiproliferative activities. The CCK-8 assay enabled us to identify a novel compound, 14g, which strongly inhibited HepG2 and A549 cell growth with IC₅₀ values of 0.54 and 0.47μM, resp. The anticancer effects might be explained by the partial activation and upregulation of PPARγ expression, as indicated by the transactivation assay and western blotting evaluation. Furthermore, the in vitro antiproliferative activity was verified in an in vivo xenograft model in which 14g strongly reduced tumor growth at a dose of 10 mg/kg. In line with these pos. observations, 14g exhibited an excellent water solubility of 31.4 mg/mL, which was more than 1000-fold higher than that of TNBG (4μg/mL). Together, these results suggest that 14g is a promising anticancer therapeutic that deserves further investigation.

761446-44-0, 1-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole is a useful research compound. Its molecular formula is C10H17BN2O2 and its molecular weight is 208.07 g/mol. The purity is usually 95%., Related Products of 761446-44-0

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. 2075-46-9, formula is C3H3N3O2, Name is 4-Nitro-1H-pyrazole. Pyrazole is a weak base, with pKb 11.5 (pKa of the conjugated acid 2.49 at 25 °C).Pyrazole used as a ligand to prepare organometallic compounds. Quality Control of 2075-46-9.

Gamonal Ruiz-Crespo, Arturo;Galan-Fernandez, Laura;Martinez-Martin, Paloma;Rodriguez-Ubis, Juan Carlos research published 《 An Orthogonal Synthetic Approach to Nonsymmetrical Bisazolyl 2,4,6-Trisubstituted Pyridines》, the research content is summarized as follows. A three-step synthetic route giving access to nonsym. bisazolyl 2,4,6-trisubstituted pyridines with different substituents on the pyrazole, indazole, and pyridine heterocycles is described. From the readily available 4-bromo-2,6-difluoropyridine, both fluorine atoms allow for easy selective stepwise substitution, and the bromine atom provides easy access to addnl. functionalities through both Suzuki and Sonogashira Pd(0) cross-coupling reactions. These synthons represent optimal structures as building blocks in complexation and metalloorg. structures for the tuning of their chelating and photophys. properties.

Quality Control of 2075-46-9, 4-Nitro-1H-pyrazole, also known as 4-Nitropyrazole, is a useful research compound. Its molecular formula is C3H3N3O2 and its molecular weight is 113.08 g/mol. The purity is usually 95%.

4-Nitropyrazole, is a building block for the synthesis of various pharmaceutical compounds, including inhibitors, and therapeutic agents. It can be used for the synthesis of highly selective, brain-penetrant aminopyrazole LRRK2 Inhibitor, as a potentially viable treatment for Parkinson’s disease., 2075-46-9.

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. Pyrazole is a weak base, with pKb 11.5 (pKa of the conjugated acid 2.49 at 25 °C).Pyrazole used as a ligand to prepare organometallic compounds. Recommanded Product: Ethyl 4-pyrazolecarboxylate.

Fotsing, Joseph R.;Darmohusodo, Vincent;Patron, Andrew P.;Ching, Brett W.;Brady, Thomas;Arellano, Melissa;Chen, Qing;Davis, Timothy J.;Liu, Hanghui;Servant, Guy;Zhang, Lan;Williams, Mark;Saganich, Michael;Ditschun, Tanya;Tachdjian, Catherine;Karanewsky, Donald S. research published 《 Discovery and Development of S6821 and S7958 as Potent TAS2R8 Antagonists》, the research content is summarized as follows. In humans, bitter taste is mediated by 25 TAS2Rs. Many compounds, including certain active pharmaceutical ingredients, excipients, and nutraceuticals, impart their bitter taste (or in part) through TAS2R8 activation. However, effective TAS2R8 blockers that can either suppress or reduce the bitterness of these compounds have not been described. We are hereby reporting a series of novel 3-(pyrazol-4-yl) imidazolidine-2,4-diones as potent and selective TAS2R8 antagonists. In human sensory tests, S6821(I) and S7958(II), two of the most potent analogs from the series, demonstrated efficacy in blocking TAS2R8-mediated bitterness and were selected for development. Following data evaluation by expert panels of a number of national and multinational regulatory bodies, including the US, the EU, and Japan, S6821 and S7958 were approved as safe under conditions of intended use as bitter taste blockers.

37622-90-5, Ethyl 4-pyrazolecarboxylate, also known as Ethyl pyrazole-4-carboxylate, is a useful research compound. Its molecular formula is C6H8N2O2 and its molecular weight is 140.14 g/mol. The purity is usually 95%.

Ethyl pyrazole-4-carboxylate is a low yield, transition metal salt that is used in the synthesis of pyrazoles. It can be synthesized by the reaction of sodium ethoxide with ethyl chloroformate and a Grignard reagent. Sodium ethoxide is added to a suspension of sodium chloride and dried ethyl chloroformate, followed by addition of magnesium turnings. The mixture is refluxed for one hour, cooled, and filtered to give crystals. Ethyl pyrazole-4-carboxylate is used in the preparation of ethyl esters from aliphatic alcohols by reacting with boron trichloride or phosphorus pentachloride. It participates in certain chemical reactions as a byproduct and can damage equipment during chemical reactions. The yield of this compound can be increased by using an excess amount of Grignard reagent or adding hexamethylenetetramine to the reaction mixture, Recommanded Product: Ethyl 4-pyrazolecarboxylate

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole is an organic compound with the formula C3H3N2H. It is a heterocycle characterized by a 5-membered ring of three carbon atoms and two adjacent nitrogen atoms, which are in ortho-substitution. 2075-46-9, formula is C3H3N3O2, Name is 4-Nitro-1H-pyrazole. Pyrazoles are a class of compounds that have the ring C3N2 with adjacent nitrogen atoms.Notable drugs containing a pyrazole ring are celecoxib (celebrex) and the anabolic steroid stanozolol. Recommanded Product: 4-Nitro-1H-pyrazole.

Floetotto, Henrik;Secker, Tim;Koegerler, Paul;Besson, Claire research published 《 Amine-Functionalized Spin Crossover Building Blocks》, the research content is summarized as follows. Bistable spin crossover complexes such as [Fe{HB(pz)₃}₂] (pzH = pyrazole) show promise for sensor applications and elec.-controlled data storage units, but exploiting their potential hinges on their integration into a functional environment. We here present a system enabling such covalent post-functionalization steps in both sym. and asym. patterns, based on the amine-functionalized complex [Fe{HB(4-NH₂pz)(pz)₂}₂], obtained by reduction of the nitro analog. The building block aspects of [Fe{HB(4-NH₂pz)(pz)₂}₂] are showcased by its transformation into amide, imine and azo derivatives, which are structurally and magnetically characterized. All tris(pyrazolyl)borate complexes retain the spin crossover properties of their parent compound, with spin crossover temperatures ranging from 350 to 430 K. The transition parameters are correlated with the electronic properties of the functionalizing group, opening the possibility of fine-tuning the spin crossover properties of the building block as it is integrated in the environment of choice.

2075-46-9, 4-Nitro-1H-pyrazole, also known as 4-Nitropyrazole, is a useful research compound. Its molecular formula is C3H3N3O2 and its molecular weight is 113.08 g/mol. The purity is usually 95%.

4-Nitropyrazole, is a building block for the synthesis of various pharmaceutical compounds, including inhibitors, and therapeutic agents. It can be used for the synthesis of highly selective, brain-penetrant aminopyrazole LRRK2 Inhibitor, as a potentially viable treatment for Parkinson’s disease., Recommanded Product: 4-Nitro-1H-pyrazole

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazoles can be selectively lithiated at different carbons and subsequently react with electrophiles depending on the substitution patterns. 2075-46-9, formula is C3H3N3O2, Name is 4-Nitro-1H-pyrazole. 1-Methyl-5-(trifluoromethyl)pyrazole underwent deprotonation and subsequent carboxylation mainly or exclusively at either the 4-position of the heterocycle or at the nitrogen-attached methyl group. Safety of 4-Nitro-1H-pyrazole.

Fleuti, Marianne;Bartova, Katerina;Slavetinska, Lenka Postova;Tloust’ova, Eva;Tichy, Michal;Gurska, Sona;Pavlis, Petr;Dzubak, Petr;Hajduch, Marian;Hocek, Michal research published 《 Synthesis and Biological Profiling of Pyrazolo-Fused 7-Deazapurine Nucleosides》, the research content is summarized as follows. A series of 8-substituted 1-methyl-1,4-dihydropyrazolo[3′,4′:4,5]pyrrolo[2,3-d]pyrimidine (methylpyrazolo-fused 7-deazapurine) ribonucleosides has been designed and synthesized. Two synthetic approaches to the key heterocyclic aglycon I, (i) a six-step classical heterocyclization starting from 5-chloro-1-methyl-4-nitropyrazole and (ii) a three-step cross-coupling and cyclization approach starting from the zinc 4,6-dichloropyrimidine, gave comparable total yield of 18% vs. 13%. The glycosylation of I was attempted by three different methods but only the Vorbruggen silyl-base protocol was efficient and stereoselective to give desired β-anomeric nucleoside intermediate. Its nucleophilic substitutions or cross-coupling reactions at position 8 and deprotection of the sugar moiety gave eight derivatives of pyrazolo-fused deazapurine ribonucleosides, e.g. II, some of which were weakly fluorescent. Me, amino and methylsulfanyl derivatives exerted sub-micromolar cytotoxic effects in vitro against a panel of cancer and leukemia cell lines, as well as antiviral effect against hepatitis C virus in the replicon assay.

Safety of 4-Nitro-1H-pyrazole, 4-Nitro-1H-pyrazole, also known as 4-Nitropyrazole, is a useful research compound. Its molecular formula is C3H3N3O2 and its molecular weight is 113.08 g/mol. The purity is usually 95%.

4-Nitropyrazole, is a building block for the synthesis of various pharmaceutical compounds, including inhibitors, and therapeutic agents. It can be used for the synthesis of highly selective, brain-penetrant aminopyrazole LRRK2 Inhibitor, as a potentially viable treatment for Parkinson’s disease., 2075-46-9.

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazoles can be selectively lithiated at different carbons and subsequently react with electrophiles depending on the substitution patterns. 761446-44-0, formula is C10H17BN2O2, Name is 1-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole. 1-Methyl-5-(trifluoromethyl)pyrazole underwent deprotonation and subsequent carboxylation mainly or exclusively at either the 4-position of the heterocycle or at the nitrogen-attached methyl group. Recommanded Product: 1-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole.

Fisher, Ethan L.;am Ende, Christopher W.;Humphrey, John M. research published 《 2,2,2-Trifluoroethoxy Aromatic Heterocycles: Hydrolytically Stable Alternatives to Heteroaryl Chlorides》, the research content is summarized as follows. The 2,2,2-trifluoroethoxy group as an alternative leaving group for hydrolytically unstable heteroaryl chlorides, is described. This group provides improved shelf stability by years while maintaining reactivity toward nucleophiles in S_NAr reactions. A highlighted trifluoroethyl ether was shown to be tolerant to aqueous Suzuki conditions, permitting sequential Suzuki/S_NAr processes inaccessible to the heterocyclic chlorides. The strategic use of trifluoroethyl ethers enables storage of otherwise unstable heterocyclic chlorides and limits costly decomposition

761446-44-0, 1-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole is a useful research compound. Its molecular formula is C10H17BN2O2 and its molecular weight is 208.07 g/mol. The purity is usually 95%., Recommanded Product: 1-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. 761446-44-0, formula is C10H17BN2O2, Name is 1-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole. Pyrazole is a weak base, with pKb 11.5 (pKa of the conjugated acid 2.49 at 25 °C).Pyrazole used as a ligand to prepare organometallic compounds. Application In Synthesis of 761446-44-0.

Finlay, M. Raymond V.;Barton, Peter;Bickerton, Sue;Bista, Michal;Colclough, Nicola;Cross, Darren A. E.;Evans, Laura;Floc′h, Nicolas;Gregson, Clare;Guerot, Carine M.;Hargreaves, David;Kang, Xiaoming;Lenz, Eva M.;Li, Xu;Liu, Yi;Lorthioir, Olivier;Martin, Matthew J.;McKerrecher, Darren;McWhirter, Claire;O′Neill, Daniel;Orme, Jonathan P.;Mosallanejad, Arash;Rahi, Amar;Smith, Paul D.;Talbot, Verity;Ward, Richard A.;Wrigley, Gail;Wylot, Marta;Xue, Lin;Yao, Tieguang;Ye, Yang;Zhao, Xiliang research published 《 Potent and Selective Inhibitors of the Epidermal Growth Factor Receptor to Overcome C797S-Mediated Resistance》, the research content is summarized as follows. The epidermal growth factor receptor (EGFR) harboring activating mutations is a clin. validated target in non-small-cell lung cancer, and a number of inhibitors of the EGFR tyrosine kinase domain, including osimertinib, have been approved for clin. use. Resistance to these therapies has emerged due to a variety of mol. events including the C797S mutation which renders third-generation C797-targeting covalent EGFR inhibitors considerably less potent against the target due to the loss of the key covalent-bond-forming residue. We describe the medicinal chem. optimization of a biochem. potent but modestly cell-active, reversible EGFR inhibitor starting point with sub-optimal physicochem. properties. These studies culminated in the identification of compound 12 that showed improved cell potency, oral exposure, and in vivo activity in clin. relevant EGFR-mutant-driven disease models, including an Exon19 deletion/T790M/C797S triple-mutant mouse xenograft model.

761446-44-0, 1-Methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole is a useful research compound. Its molecular formula is C10H17BN2O2 and its molecular weight is 208.07 g/mol. The purity is usually 95%., Application In Synthesis of 761446-44-0

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazoles and pyrimidines have diverse biological and pharmacological activities. 269410-08-4, formula is C9H15BN2O2, Name is 4-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole. There are a number of antimicrobial compounds containing pyrazole moiety as the core unit. Electric Literature of 269410-08-4.

Finlay, Heather J.;Johnson, James A.;Lloyd, John L.;Jiang, Ji;Neels, James;Gunaga, Prashantha;Banerjee, Abhisek;Dhondi, Naveen;Chimalakonda, Anjaneya;Mandlekar, Sandhya;Conder, Mary Lee;Sale, Harinath;Xing, Dezhi;Levesque, Paul;Wexler, Ruth R. research published 《 Discovery of 5-Phenyl-N-(pyridin-2-ylmethyl)-2-(pyrimidin-5-yl)quinazolin-4-amine as a Potent I_Kur Inhibitor》, the research content is summarized as follows. A new series of phenylquinazoline inhibitors of K_v 1.5 is disclosed. The series was optimized for K_v 1.5 potency, selectivity vs. hERG, pharmacokinetic exposure, and pharmacodynamic potency. 5-Phenyl-N-(pyridin-2-ylmethyl)-2-(pyrimidin-5-yl)quinazolin-4-amine (13k) was identified as a potent and ion channel selective inhibitor with robust efficacy in the preclin. rat ventricular effective refractory period (VERP) model and the rabbit atrial effective refractory period (AERP) model.

269410-08-4, 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole, also known as 4-Pyrazoleboronic acid pinacol ester , is a useful research compound. Its molecular formula is C9H15BN2O2 and its molecular weight is 194.04 g/mol. The purity is usually 95%.

4-Pyrazoleboronic acid pinacol ester is a useful reagent for Suzuki-Miyaura cross-couplings as well as Ruthenium-catalyzed asymmetric hydrogenation. 4-Pyrazoleboronic acid pinacol ester is also a useful reagent for preparing VEGF, Aurora, RHO (ROCK), Janus Kinase 2, c-MET, ALK, S-nitrsoflutathione reductase, CDC7, Acetyl-CoA carboxylase inhibitors.

4-Pyrazoleboronic acid pinacol ester is used in the preparation of Rho kinase (ROCK) inhibitors as wella s other biologically active compounds.

4-Pyrazoleboronic acid pinacol ester is an organic compound that is the product of a bifunctional coupling reaction between 4-pyrazolecarboxylic acid and pinacol. It has been shown to inhibit protein S6 kinase, which is involved in the regulation of cell growth and proliferation. This compound has also been shown to be effective against cancer cells, including those that are resistant to conventional chemotherapeutic drugs. 4-Pyrazoleboronic acid pinacol ester may also be used as a precursor for other compounds with pharmaceutical activity., Electric Literature of 269410-08-4

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazoles are synthesized by the reaction of α,β-unsaturated aldehydes with hydrazine and subsequent dehydrogenation. 2075-46-9, formula is C3H3N3O2, Name is 4-Nitro-1H-pyrazole. Substituted pyrazoles are prepared by condensation of 1,3-diketones with hydrazine (Knorr-type reactions). For example, acetylacetone and hydrazine gives 3,5-dimethylpyrazole. Computed Properties of 2075-46-9.

Fernandez, Belen;Fernandez, Ignacio;Cepeda, Javier;Medina-ODonnell, Marta;Rufino-Palomares, Eva E.;Raya-Baron, Alvaro;Gomez-Ruiz, Santiago;Perez-Jimenez, Amalia;Lupianez, Jose Antonio;Reyes-Zurita, Fernando J.;Rodriguez-Dieguez, Antonio research published 《 Modulating Anticancer Potential by Modifying the Structural Properties of a Family of Zinc Metal-Organic Chains Based on 4-Nitro-1H-pyrazole》, the research content is summarized as follows. The authors synthesized a novel family of metal-organic chains based on 4-nitro-1H-pyrazole linker and zinc as metal center. The authors report the formation of these coordination polymers using hydrothermal routes with water as solvent. These materials display one-dimensional structures with major structural modifications from minimal synthetic variations. What is more interesting, the authors have carried out antitumor measurements, and the authors have related these properties with the structural networks. To the best of the authors’ knowledge, these materials constitute the first examples of polymeric structures for 4-NO₂-pz ligands. NMR and MS spectrometry were used to verify the characterization of the metal complexes in solution to corroborate that these materials are present in the biol. assays.

Computed Properties of 2075-46-9, 4-Nitro-1H-pyrazole, also known as 4-Nitropyrazole, is a useful research compound. Its molecular formula is C3H3N3O2 and its molecular weight is 113.08 g/mol. The purity is usually 95%.

4-Nitropyrazole, is a building block for the synthesis of various pharmaceutical compounds, including inhibitors, and therapeutic agents. It can be used for the synthesis of highly selective, brain-penetrant aminopyrazole LRRK2 Inhibitor, as a potentially viable treatment for Parkinson’s disease., 2075-46-9.

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole is an organic compound with the formula C3H3N2H. It is a heterocycle characterized by a 5-membered ring of three carbon atoms and two adjacent nitrogen atoms, which are in ortho-substitution. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. Pyrazoles are a class of compounds that have the ring C3N2 with adjacent nitrogen atoms.Notable drugs containing a pyrazole ring are celecoxib (celebrex) and the anabolic steroid stanozolol. Electric Literature of 37622-90-5.

Fernandes, Celia;Maria, Leonor;Gano, Lurdes;Santos, Isabel C.;Santos, Isabel;Paulo, Antonio research published 《 Re(I) and ^99mTc(I) tricarbonyl complexes with ether-containing pyrazolyl-based chelators: Chemistry, biodistribution and metabolism》, the research content is summarized as follows. Tris(pyrazolyl)methane chelators, L1-L3, containing one or two ether groups at different positions of the azole rings, were synthesized and fully characterized. These chelators enabled the synthesis of fac-[^99mTc(CO)₃{HC[4-(ROCH₂)pz]₃}]⁺ (R = Me (Tc1), Et (Tc2)) and fac-[^99mTc(CO)₃{HC[3,5-(EtOCH₂)₂pz]₃}]⁺ (Tc3) which were identified by HPLC in comparison with the rhenium counterparts. The evaluation of Tc1-Tc3 in CD-1 mice showed that the number and/or nature of the ether groups greatly influence the biodistribution profile, pharmacokinetics and metabolic stability of these complexes. Tc1 and Tc2, bearing a unique ether substituent at the 4-position of the pyrazolyl ring, undergo metabolic transformation in vivo while Tc3 is not metabolized. The metabolization of Tc1 and Tc2 enhanced their rate of excretion but, most probably, also justify their negligible heart uptake in contrast with the high heart uptake of congener non-metabolizable complexes (^99mTc-DMEOP and ^99mTc-TMEOP), which have recently emerged as potential myocardial imaging agents. The attempts made to identify the metabolites of Tc1 and Tc2 showed that the metabolization of these compounds must involve the ether functions with probable formation of carboxylic acid derivatives A comparative study with the congener fac-[^99mTc(CO)₃{[4-(MeOCH₂)pz](CH₂)₂NH(CH₂)₂NH₂}]⁺ (Tc6) led the authors to confirm the formation of such type of metabolites. In fact, Tc6 is also metabolized in mice with formation of fac-[^99mTc(CO)₃{[4-(HOCH₂)pz](CH₂)₂NH(CH₂)₂NH₂}]⁺ (Tc7) and fac-[^99mTc(CO)₃{[4-(HOOC)pz](CH₂)₂NH(CH₂)₂NH₂}]⁺ (Tc8), which were chem. identified by HPLC in comparison with the Re congeners (Re7 and Re8).

37622-90-5, Ethyl 4-pyrazolecarboxylate, also known as Ethyl pyrazole-4-carboxylate, is a useful research compound. Its molecular formula is C6H8N2O2 and its molecular weight is 140.14 g/mol. The purity is usually 95%.

Ethyl pyrazole-4-carboxylate is a low yield, transition metal salt that is used in the synthesis of pyrazoles. It can be synthesized by the reaction of sodium ethoxide with ethyl chloroformate and a Grignard reagent. Sodium ethoxide is added to a suspension of sodium chloride and dried ethyl chloroformate, followed by addition of magnesium turnings. The mixture is refluxed for one hour, cooled, and filtered to give crystals. Ethyl pyrazole-4-carboxylate is used in the preparation of ethyl esters from aliphatic alcohols by reacting with boron trichloride or phosphorus pentachloride. It participates in certain chemical reactions as a byproduct and can damage equipment during chemical reactions. The yield of this compound can be increased by using an excess amount of Grignard reagent or adding hexamethylenetetramine to the reaction mixture, Electric Literature of 37622-90-5

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics