Day: January 4, 2023

Synthesis and pharmacological screening of pyrazolopyridine compounds as anxiolytics was written by Kushwah, Shruti;Prajapati, Krunal;Darji, Nilesh;Soni, Palak;Shah, Parita. And the article was included in International Journal of Pharmaceutical Research and Bio-Science in 2012.Name: 1-Ethyl-1H-pyrazol-5-amine This article mentions the following:

Amine and chloro derivatives of Et 4-substituted-6-phenyl-4,7-dihydro-1H-pyrazolo[3,4-b]pyridine-5-carboxylate and carboxylic acid were synthesized using liquid ammonia and phosphorous oxychloride from 1-pentyl-5 amino pyrazole, resp. 3-Amino-2 substituted-4,7-dihydro-2H-Pyrazolo[4,3-c]pyridine-4,6-diol were synthesized from 3-cyanomethyl-4-cyano-5-amino-1-substituted pyrazole using active Me ene compound, Malononitrile and substituted hydrazine. Pyrazolo[3,4-b]pyridinone was synthesized from 3-amino-1-Ph pyrazolone and acetylacetone. Completion of reactions was checked by TLC using hexane:ethyl acetate as mobile phase. Reagents like Di-Et Benzoyl malonate & β-Cyano Ethylhydrazine were also synthesized. All the synthesized compounds were characterized by IR, Mass and NMR anal. & by m.p. & TLC phys. The synthesized compounds were tested using Elevated Plus Maze model. In the experiment, the researchers used many compounds, for example, 1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3Name: 1-Ethyl-1H-pyrazol-5-amine).

1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3) belongs to pyrazole derivatives. An alternative way to synthesize multisubstituted pyrazoles is the Csingle bondH arylation of simple pyrazoles. Pyrazoles can be selectively lithiated at different carbons and subsequently react with electrophiles depending on the substitution patterns.Name: 1-Ethyl-1H-pyrazol-5-amine

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

Application of a multi-SO₃H Bronsted acidic ionic liquid in water: a highly efficient and reusable catalyst for the regioselective and scaled-up synthesis of pyrazoles under mild conditions was written by Safaei, Shirin;Mohammadpoor-Baltork, Iraj;Khosropour, Ahmad Reza;Moghadam, Majid;Tangestaninejad, Shahram;Mirkhani, Valiollah;Kia, Reza. And the article was included in RSC Advances in 2012.Application In Synthesis of 3,5-Dimethyl-1H-pyrazole-1-carboxamide This article mentions the following:

An elegant and efficient procedure with exceptionally mild conditions for the regioselective synthesis of pyrazoles by the reaction of various 1,3-diketones and hydrazines/hydrazides using a multi-SO₃H Bronsted acidic room temperature ionic liquid as a powerful catalyst in aqueous media has been developed. The ionic liquid was easily separated from the reaction mixture and was recycled and used for at least six consecutive runs without any loss of activity. In the experiment, the researchers used many compounds, for example, 3,5-Dimethyl-1H-pyrazole-1-carboxamide (cas: 934-48-5Application In Synthesis of 3,5-Dimethyl-1H-pyrazole-1-carboxamide).

3,5-Dimethyl-1H-pyrazole-1-carboxamide (cas: 934-48-5) belongs to pyrazole derivatives. As is the case with imidazoles, the pyrazole ring offers many opportunities to create new multiring systems that incorporate this heterocycle. The presence of both electronegative nitrogen atoms in the pyrazole ring reduces the electron density of the C3- and C5-positions leaving electron density of C4-position unaltered. Thus the C4-position is vulnerable to electrophilic attack. The C3 electrophilic-position may undergo deprotonation in the presence of a strong base leading to ring opening.Application In Synthesis of 3,5-Dimethyl-1H-pyrazole-1-carboxamide

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

Studies in the field of nitrogen heterocyclic compounds. Part XVI. A novel Dimroth type rearrangement of some 1-amino-2-pyridone derivatives was written by Balicki, Roman. And the article was included in Polish Journal of Chemistry in 1984.Safety of 3-(Trifluoromethyl)-1H-pyrazol-5(4H)-one This article mentions the following:

Cyclocondensation of RCOCH₂CO₂Et [R = Me, pyridyl, (substituted) Ph, CF₃, CO₂Et] with H₂NNHCOCH₂CN in EtOH/KOH gave the aminopyridone salts I (R¹ = K) (II). On treatment with acid, II (R = CF₃, CO₂Et), possessing strong electron-withdrawing groups at C-4, underwent the title rearrangement to give pyrazolopyridines III, whereas the other II gave the expected aminopyridones I (R¹ = H). The mechanism of the rearrangement is discussed. In the experiment, the researchers used many compounds, for example, 3-(Trifluoromethyl)-1H-pyrazol-5(4H)-one (cas: 401-73-0Safety of 3-(Trifluoromethyl)-1H-pyrazol-5(4H)-one).

3-(Trifluoromethyl)-1H-pyrazol-5(4H)-one (cas: 401-73-0) belongs to pyrazole derivatives. The strategies for the synthesis of pyrazoles generally can be applied for the construction of indazoles. Protonation of pyrazole in strong acid leads to pyrazolium cations, which undergo electrophilic substitution preferentially at C3 rather than C4. The pyrazole anion is not reactive toward nucleophiles but is mostly reactive to electrophiles.Safety of 3-(Trifluoromethyl)-1H-pyrazol-5(4H)-one

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

Discovery of pyrazole N-aryl sulfonate: A novel and highly potent cyclooxygenase-2 (COX-2) selective inhibitors was written by Yao, Haiyan;Guo, Quanping;Wang, Mengran;Wang, Rui;Xu, Zhaoqing. And the article was included in Bioorganic & Medicinal Chemistry in 2021.Product Details of 19959-77-4 This article mentions the following:

Based on a new pyrazole sulfonate synthetic method, a novel class of mols. 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 Ph 5-methyl-3-(4-(trifluoromethyl) phenyl)-1H-pyrazole-1-sulfonate exhibited excellent anti-inflammatory activity (% inhibition of auricular edemas = 27.0 and 35.9, resp.); the in vivo analgesic activity of Ph 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% sep.), and compounds Ph 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 LD 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. In the experiment, the researchers used many compounds, for example, 2-(5-Methyl-1H-pyrazol-3-yl)pyridine (cas: 19959-77-4Product Details of 19959-77-4).

2-(5-Methyl-1H-pyrazol-3-yl)pyridine (cas: 19959-77-4) belongs to pyrazole derivatives. The strategies for the synthesis of pyrazoles generally can be applied for the construction of indazoles. The pyrazole ring is resistant to oxidation and reduction but the groups, such as alkyl and formyl attached to the ring, are oxidized to respective acids. Only electrolytic oxidation, ozonolysis, and a strong base cause ring opening.Product Details of 19959-77-4

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

Complexing of copper(I) nitrate with pyrazole derivatives in acetonitrile and their interaction with oxygen was written by Myagchenko, A. P.;Motyagina, G. G.. And the article was included in Ukrainskii Khimicheskii Zhurnal (Russian Edition) in 1987.Product Details of 5334-39-4 This article mentions the following:

The complexing of Cu(NO₃) with 3(5)-methylpyrazoles and some primary amines was studied by potentiometric titration in MeCN under Ar atm. Introduction of these ligands has almost no effect on the elec. conductivity of the initial Ca(NO₃) solutions Solvent mols. are replaced by the added ligands to give 1:1 complexes. Complex stabilities are lower with primary amine ligands when both amine and pyrazole ligands have the same proton affinities since the amines can only act as σ donors. The increase in stability due to pyrazole π-dative bonding capability was calculated In the experiment, the researchers used many compounds, for example, 3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4Product Details of 5334-39-4).

3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4) belongs to pyrazole derivatives. Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. Pyrazoles are commonly used scaffold molecules in drug discovery projects. The use of pyrazole derivatives is based on their analgesic, anti-inflammatory, antipyretic, antiarrhythmic, sedative, muscle relaxant, neuroleptic, anticonvulsant, monoamine oxidase inhibitory, antidiabetic and antibacterial activities.Product Details of 5334-39-4

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

Novel facile synthesis of 2,2,4-substituted-1,2-dihydroquinolines via a modified Skraup reaction was written by Theoclitou, Maria-Elena;Robinson, Leslie A.. And the article was included in Tetrahedron Letters in 2002.Application of 3528-58-3 This article mentions the following:

A variety of 2,2,4-substituted-1,2-dihydroquinolines were synthesized from substituted anilines or aminoheterocycles and the corresponding ketones in good yield via the use of lanthanide catalysts and microwave technol. This method can be readily applied to the general synthesis of combinatorial libraries of dihydroquinolines. In the experiment, the researchers used many compounds, for example, 1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3Application of 3528-58-3).

1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3) belongs to pyrazole derivatives. 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. Pyrazoles and pyrimidines have diverse biological and pharmacological activities. There are a number of antimicrobial compounds containing pyrazole moiety as the core unit. Pyrazofurin is important antimicrobial drug and 2-methylpyrimidine-4-ylamine derivatives I and II were found to be effective inhibitors of Escherichia coli PDHc-E1 with antibacterial and antifungal activity.Application of 3528-58-3

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

High resolution carbon-13 nuclear magnetic resonance spectra of solid pyrazoles. Application to annular tautomerism was written by Faure, Robert;Vincent, Emile Jean;Rousseau, Andre;Claramunt, Rose Maria;Elguero, Jose. And the article was included in Canadian Journal of Chemistry in 1988.Quality Control of 3-Methyl-4-nitro-1H-pyrazole This article mentions the following:

Carbon-13 NMR spectroscopy in the solid state (cross polarization/magic angle spinning technique) is a very suitable method for studying the annular tautomerism of pyrazoles. In all the compounds studied, the tautomerism is frozen and the signals are well resolved except for 3,5-dimethyl-4-nitropyrazole, which shows broad signals. In the case of 4-substituted derivatives of 3(5)-methylpyrazoles, the tautomer present in the solid state is a 4-X-5 methylpyrazole. 3-Phenyl-5-methylpyrazole (4H or 4-methyl) is favored over the 3-methyl-5-phenyl-tautomer. In the experiment, the researchers used many compounds, for example, 3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4Quality Control of 3-Methyl-4-nitro-1H-pyrazole).

3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4) belongs to pyrazole derivatives. Pyrazole has two ring nitrogen atoms in which N1 is pyrrolic and N2 is pyridine-like. The N1 nitrogen is not reactive but is deprotonated in the presence of a base-forming anion. Protonation of pyrazole in strong acid leads to pyrazolium cations, which undergo electrophilic substitution preferentially at C3 rather than C4. The pyrazole anion is not reactive toward nucleophiles but is mostly reactive to electrophiles.Quality Control of 3-Methyl-4-nitro-1H-pyrazole

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

Polarographic and electrochemical studies of some aromatic and heterocyclic nitro compounds. Part III: Electroreduction of mono- and dinitropyrazoles and -imidazoles was written by Dumanovic, D.;Jovanovic, J.;Suznjevic, D.;Erceg, M.;Zuman, P.. And the article was included in Electroanalysis in 1992.Product Details of 54210-32-1 This article mentions the following:

The reduction of mono- and dinitropyrazoles and of nitroimidazoles follows the general pattern of reduction of aromatic nitro compounds: the nitro group is reduced in a 4-electron step to a hydroxylamino group and the protonated form of the hydroxylamino group is – in the lower pH range – further reduced to an amine. This reduction differs from that of nitrobenzenes in participation of a 2nd hydrogen ion probably involved in protonation of the heterocyclic ring. This 2nd proton is for nitroimidazoles transferred before the uptake of the 1st electron, for nitropyrazoles probably after this uptake. The transfer of the 2nd electron is the potential determining step. The 2 sequences are H⁺, H⁺, e, H⁺, e, 2e, H⁺ and H⁺, e, H⁺, H⁺, e, 2e, H⁺, resp. For nitropyrazoles and nitroimidazoles without an alkyl substituent on the ring N, the reduction process is further complicated by the dissociation of the NH-group in the heterocyclic ring. For 1-alkyl-5-nitroimidazoles, for 4(5)-nitroimidazole and for N-unsubstituted-4- and 3(5)-nitropyrazoles (but not for 2-nitroimidazoles, 1-alkyl-4-nitroimidazoles and 1-alkylnitropyrazoles) the hydroxylamino derivative formed in the 1st 4-electron step undergoes a base catalyzed dehydration yielding a quinone-like ketimine. Easy reduction of this species results in alk. solutions in a limiting current which is significantly higher than corresponds to a 4-electron and limits to a 6-electron reduction Such dehydration reactions occur considerably faster for dihydroxylamino derivatives formed in the reduction of dinitropyrazoles resulting in 2 waves with total transfer of up to 12 electrons. In the experiment, the researchers used many compounds, for example, 1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1Product Details of 54210-32-1).

1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1) belongs to pyrazole derivatives. Pyrazole has two ring nitrogen atoms in which N1 is pyrrolic and N2 is pyridine-like. The N1 nitrogen is not reactive but is deprotonated in the presence of a base-forming anion. The presence of both electronegative nitrogen atoms in the pyrazole ring reduces the electron density of the C3- and C5-positions leaving electron density of C4-position unaltered. Thus the C4-position is vulnerable to electrophilic attack. The C3 electrophilic-position may undergo deprotonation in the presence of a strong base leading to ring opening.Product Details of 54210-32-1

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

Facile, Fast and Safe Process Development of Nitration and Bromination Reactions Using Continuous Flow Reactors was written by Pelleter, Jacques;Renaud, Fabrice. And the article was included in Organic Process Research & Development in 2009.Category: pyrazoles-derivatives This article mentions the following:

Chemists working in a pilot plant often face safety issues during scale-up operations. With the help of emerging microfluidic applications and microdevices, running hazardous, highly exothermic or potentially unstable reactions can be easily transposed into a safe continuous flow mode. Potentially hazardous pyrazole nitration and the bromination of a variety of electron-rich heteroaromatic substrates were efficiently performed using an inexpensive and easily available system for bench chemists. Advantages of the continuous flow mode in organic synthetic chem. are illustrated by the large-scale production of raw materials under safe, green and reproducible conditions. In the experiment, the researchers used many compounds, for example, 3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4Category: pyrazoles-derivatives).

3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4) belongs to pyrazole derivatives. 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. Pyrazoles are commonly used scaffold molecules in drug discovery projects. The use of pyrazole derivatives is based on their analgesic, anti-inflammatory, antipyretic, antiarrhythmic, sedative, muscle relaxant, neuroleptic, anticonvulsant, monoamine oxidase inhibitory, antidiabetic and antibacterial activities.Category: pyrazoles-derivatives

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

Synthesis and biological activity of novel Pyrazolo[3,4-d]pyrimidin-4-one derivatives as potent antifungal agent was written by Wang, Wei;Cheng, Xiang;Cui, Xue;Xia, Dongguo;Wang, Ziqing;Lv, Xianhai. And the article was included in Pest Management Science in 2021.Synthetic Route of C11H11N3O2 This article mentions the following:

To promote the discovery and development of new fungicide with novel scaffolds or modes of action, a series of novel 5-(2-chloroethyl)-1-phenyl-6-(pyridin-4-yl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyrimidin-4-one derivatives I [R¹ = pyridin-3-yl, pyridin-4-yl, 2-chloropyridin-3-yl, etc.; R² = H, Me, F, Cl; R³ = H, Me] were synthesized and evaluated for their antifungal activities. The bioassay data showed that compound I [R¹ = 6-chloropyridin-3-yl, R² = Cl, R³ = H] (EC₅₀ = 1.93 mg L^-1) was superior to boscalid (EC₅₀ = 6.71 mg L^-1) against Valsa mali. Chiral groups was introduced on the structure of cmpnd. I [R¹ = 6-chloropyridin-3-yl, R² = Cl, R³ = H] and two chiral configurations were resp. synthesized, which were (R/S) I [R¹ = 2-chloropyridin-3-yl, R² = Cl, R³ = Me]. Surprisingly, cmpnd. (S) I [R¹ = 2-chloropyridin-3-yl, R² = Cl, R³ = Me] showed significant antifungal activities against Valsa mali and Physalospora piricola with EC₅₀ values of 0.22 and 0.55 mg L^-1. Physiol. and biochem. studies showed that the primary action mechanism of compound (S) I [R¹ = 2-chloropyridin-3-yl, R² = Cl, R³ = Me] on Valsa mali may involve changing mycelial morphol. and increasing cell membrane permeability. These results demonstrated that cmpnd. (S) I [R¹ = 2-chloropyridin-3-yl, R² = Cl, R³ = Me] was modified as fungicide and provided a valuable reference for antifungal agents with pyrazolo[3,4-d]pyrimidin-4-one skeleton. In the experiment, the researchers used many compounds, for example, 5-Amino-1-(p-tolyl)-1H-pyrazole-4-carboxylic acid (cas: 14678-93-4Synthetic Route of C11H11N3O2).

5-Amino-1-(p-tolyl)-1H-pyrazole-4-carboxylic acid (cas: 14678-93-4) belongs to pyrazole derivatives. Pyrazoles, a five-membered heterocycle containing two adjacent nitrogen atoms, are the core structures found in a number of molecules that possess a wide range of pharmaceutical and agricultural activities. Pyrazoles and pyrimidines have diverse biological and pharmacological activities. There are a number of antimicrobial compounds containing pyrazole moiety as the core unit. Pyrazofurin is important antimicrobial drug and 2-methylpyrimidine-4-ylamine derivatives I and II were found to be effective inhibitors of Escherichia coli PDHc-E1 with antibacterial and antifungal activity.Synthetic Route of C11H11N3O2

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