pyrazoles-derivatives

Molybdenum-silver co-catalyzed cycloaddition of alkynes with N-isocyanoiminotriphenylphosphorane (NIITP): An efficient strategy for the synthesis of monosubstituted pyrazoles was written by Mi, Pengbing;Lang, Jiajia;Lin, Shaojian. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2019.Safety of 3-(4-Bromophenyl)-1H-pyrazole This article mentions the following:

A new molybdenum-silver co-catalyzed [3+2]-cycloaddition of alkynes RCCH (R = 4-FC₆H₄, cyclopentyl, pyridin-2-yl, etc.) with N-isocyanoiminotriphenylphosphorane (NIITP) is described. The NIITP serves as a non-toxic, facile “CN-N” source. Over 30 substrates were successfully converted to the desired pyrazole compounds I in good to excellent yields. In the experiment, the researchers used many compounds, for example, 3-(4-Bromophenyl)-1H-pyrazole (cas: 73387-46-9Safety of 3-(4-Bromophenyl)-1H-pyrazole).

3-(4-Bromophenyl)-1H-pyrazole (cas: 73387-46-9) belongs to pyrazole derivatives. Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. 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-(4-Bromophenyl)-1H-pyrazole

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

Formation of Nitrosopyrazolidones and Pyrazolones from the Hydrazides of Unsaturated Acids was written by Muckermann, Ernst. And the article was included in Berichte der Deutschen Chemischen Gesellschaft in 1910.Recommanded Product: 51395-52-9 This article mentions the following:

Cinnamic hydrazide, PhCH : CHCONHNH₂, prepared from ethyl cinnamate and hydrazine hydrate, crystallizes in bundles of colorless, slender, interlaced needles, m. 101°. It has been described previously as an oil. Yield, 52.1-4.3%. Hydrochloride, from absolute alc. HCl; crystalline, becomes yellow about 190°, m. and evolves gas 201°. Yield, 89.7-93.8%. Benzal derivative, light yellow flocks, softens about 170°, m. 180°. Yield, about 112% of the hydrazide. I-Nitroso-5-phenyl-3-pyrazolidone, formula (I) below, is prepared from cinnamic hydrazide, HCl and NaNO₂; slender, colorless needles, becomes yellow about 115°, m. and decomposes 127-8°. It burns with a smoky flame, is soluble in dilute aqueous NaOH and exhibits Liebermann’s reaction. Yield, 86-90% of the hydrazide hydrochloride. When treated with glacial AcOH and Br it gives 3-phenyl-4,4-dibromo-5-pyrazolone (II); m. 198° not 189°. Boiling, concentrate HCl hydrolyzes (I) to cinnamic acid, but dilute H₂SO₄ (d. 1.06), under similar conditions, converts it into 4-isonitroso-3-phenylpyrazolone (III), gas being evolved during the earlier stages of the reaction. Crotonic hydrazide could only be obtained as an oil which was not pure. It is somewhat unstable. Hydrochloride, MeCH:CHCONHNH₂.HCl, slender, colorless, rather unstable needles, m. and evolves gas 173°. Yield, 87.9%. Benzal derivative, light yellow and insoluble, m. 72°. Yield, 60% of the hydrazide. 1-Nitroso-5-methyl-3-pyrazolidone is prepared in a similar manner to the Ph derivative (1); colorless, lustrous plates, m. and evolves gas 131°. It is soluble in aqueous NaOH or NH₃, gives a cherry-red color with FeCl₃ and exhibits Liebermann’s reaction. Yield, 60-76% of the hydrazide hydrochloride. Glacial AcOH and Br, at 0°, convert it into 3-methyl-4-bromo-5-pyrazolone (IV), which was prepared for comparison from 3-methylpyrazolone; colorless, thick, hexagonal plates, m. 182°. Yield about 100% of the nitroso compound. Under similar conditions, at the ordinary temperature, the nitroso compound gives 3-methyl-4,4-dibromo-5-pyrazolone. In the experiment, the researchers used many compounds, for example, 4-Bromo-3-methyl-1H-pyrazol-5(4H)-one (cas: 51395-52-9Recommanded Product: 51395-52-9).

4-Bromo-3-methyl-1H-pyrazol-5(4H)-one (cas: 51395-52-9) 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 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.Recommanded Product: 51395-52-9

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

High Throughput Synthesis of Extended Pyrazolo[3,4-d]dihydropyrimidines was written by Ryabukhin, Sergey V.;Granat, Dmitry S.;Plaskon, Andrey S.;Shivanyuk, Alexander N.;Tolmachev, Andrey A.;Volovenko, Yulian M.. And the article was included in ACS Combinatorial Science in 2012.Application In Synthesis of 1-Ethyl-1H-pyrazol-5-amine This article mentions the following:

Fused pyrazolo[3,4-d]pyrimidines such as I (R = Ph, 4-MeOC₆H₄, 4-ClC₆H₄, 5-phenyl-2-furanyl, 1-phenyl-4-pyrazolyl, 3,4-Me₂C₆H₃, 3-F₃CC₆H₄, 3-Me-2-thienyl, 3-ClC₆H₄, 5-Me-2-furanyl, 3,5-dimethyl-4-isoxazolyl, 3,4-Cl₂C₆H₃, 2-FC₆H₄, 3-FC₆H₄, 4-Me₂NC₆H₄, 2-F₂CHOC₆H₄; R¹ = H; R² = H, F₃C, Me₂NSO₂, 1-pyrrolidinylsulfonyl, 1-piperidinylsulfonyl, 4-morpholinylsulfonyl; R¹R² = benzo) were prepared in two steps from 1-substituted-5-pyrazoleamines such as 1-isopropyl-5-pyrazoleamine, heteroaryl chlorides such as 2-chloropyridine, and aldehydes such as benzaldehyde. N-heteroaryl 5-pyrazoleamines such as II (R¹ = H; R² = H, F₃C, 1-piperidinylsulfonyl; R¹R² = benzo) were generated by base-mediated condensation of 5-pyrazoleamines such as 1-phenyl-3-methyl-5-pyrazoleamine with heteroaryl chlorides such as 2-chloropyridine; heating the heteroaryl pyrazoleamines with aryl aldehydes or isatins either in a sealed tube with trimethylsilyl chloride or in glacial acetic acid followed by crystallization yielded pyrazolo[3,4-d]pyrimidines. Reaction of N-heteroaryl 5-pyrazoleamines with cyclohexanone provided N-heteroaryl 4-(1-cyclohexen-1-yl)-5-pyrazoleamines rather than spirocyclohexanepyrazolopyrimidines. A library of > 200 pyrazolo[3,4-d]pyrimidines were prepared; the distribution of the library members within ranges of lipophilicity, mol. weight, hydrogen bond acceptor and donor count, and polar surface area was determined In the experiment, the researchers used many compounds, for example, 1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3Application In Synthesis of 1-Ethyl-1H-pyrazol-5-amine).

1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3) 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. 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.Application In Synthesis of 1-Ethyl-1H-pyrazol-5-amine

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

Greener and facile aqueous synthesis of pyrazoles using Amberlyst-70 as a recyclable catalyst was written by Chandak, Hemant S.;Lad, Nitin P.;Dange, Dipali S.. And the article was included in Green Chemistry Letters and Reviews in 2012.Category: pyrazoles-derivatives This article mentions the following:

An environmentally benign, room temperature aqueous synthesis of pyrazoles by the condensation of hydrazines/hydrazides with 1,3-diketones using Amberlyst-70 as a recyclable catalyst was described. The use of resinous, non-toxic, thermally stable and inexpensive Amberlyst-70 as a heterogeneous catalyst and simple reaction workup are the addnl. eco-friendly attributes of this synthetic protocol. In the experiment, the researchers used many compounds, for example, 3,5-Dimethyl-1H-pyrazole-1-carboxamide (cas: 934-48-5Category: pyrazoles-derivatives).

3,5-Dimethyl-1H-pyrazole-1-carboxamide (cas: 934-48-5) 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.Category: pyrazoles-derivatives

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

Brightly luminescent lanthanide pyrazolecarboxylates: Synthesis, luminescent properties and influence of ligand isomerism was written by Utochnikova, Valentina V.;Abramovich, Maxim S.;Latipov, Egor V.;Dalinger, Alexander I.;Goloveshkin, Alexander S.;Vashchenko, Andrey A.;Kalyakina, Alena S.;Vatsadze, Sergey Z.;Schepers, Ute;Brase, Stefan;Kuzmina, Natalia P.. And the article was included in Journal of Luminescence in 2019.Safety of 1-Methyl-5-phenyl-1H-pyrazole-3-carboxylic acid This article mentions the following:

The complexes of the formula Ln(carb)₃(H₂O)₂ (where Ln = Eu, Tb, Gd, La, Yb; carb = various pyrazolecarboxylic acids) were synthesized and thoroughly characterized. It was shown that the quantum yields of terbium complexes depend mainly on the type of substituents of the ligand, while the quantum yields of europium complexes are influenced by the ligand isomerism due to the presence or absence of the ligand-to-metal charge transfer (LMCT) state. These compounds were successfully tested as bioimaging probes as well as OLED emitting layers due to their high photo- and electroluminescent performance. In the experiment, the researchers used many compounds, for example, 1-Methyl-5-phenyl-1H-pyrazole-3-carboxylic acid (cas: 10199-53-8Safety of 1-Methyl-5-phenyl-1H-pyrazole-3-carboxylic acid).

1-Methyl-5-phenyl-1H-pyrazole-3-carboxylic acid (cas: 10199-53-8) belongs to pyrazole derivatives. Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. Pyrazole rings have been used as core components of several leading non-steroidal anti-inflammatory drugs (NSAIDs) and antihypertensive drugs. It has also been found to be useful as a bifunctional ligand for metal catalysis.Safety of 1-Methyl-5-phenyl-1H-pyrazole-3-carboxylic acid

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

Substituent effects on the ¹⁵N NMR parameters of azoles was written by Claramunt, Rosa Maria;Sanz, Dionisia;Lopez, Concepcion;Jimenez, Jose Antonio;Jimeno, Maria Luisa;Elguero, Jose;Fruchier, Alain. And the article was included in Magnetic Resonance in Chemistry in 1997.Synthetic Route of C4H5N3O2 This article mentions the following:

The ¹⁵N chem. shifts and a large collection of coupling constants pertaining to azoles have been gathered from the literature. To complete this collection and to check some anomalies, the spectra of 14 compounds in several solvents were recorded again and 31 compounds were studied for the first time; in all, data for 420 compounds (pyrroles, imidazoles, pyrazoles, triazoles, tetrazoles, indoles, benzimidazoles, indazoles, benzotriazoles and carbazoles) are reported. Additive models are used to discuss the substituent chem. shifts. In the experiment, the researchers used many compounds, for example, 1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1Synthetic Route of C4H5N3O2).

1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1) 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. 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.Synthetic Route of C4H5N3O2

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

Microwave-assisted palladium mediated efficient synthesis of pyrazolo[3,4-b]pyridines, pyrazolo[3,4-b]quinolines, pyrazolo[1,5-a]pyrimidines and pyrazolo[1,5-a]quinazolines was written by Shekarrao, Kommuri;Kaishap, Partha Pratim;Saddanapu, Venkateshwarlu;Addlagatta, Anthony;Gogoi, Sanjib;Boruah, Romesh C.. And the article was included in RSC Advances in 2014.Application In Synthesis of 1-Ethyl-1H-pyrazol-5-amine This article mentions the following:

An efficient method for the synthesis of pyrazole-fused heterocycles via the palladium-catalyzed solvent-free reaction of β-halovinyl or o-haloaryl aldehydes and 3-aminopyrazoles or 5-aminopyrazoles under microwave irradiation conditions in good yields was developed. This method is applicable for the efficient synthesis of a wide range of substituted pyrazolo[3,4-b]pyridines, e.g., I, pyrazolo[3,4-b]quinolines, e.g., II, pyrazolo[1,5-a]pyrimidines, e.g., III (R¹ = H, Me, 4-MeOC₆H₄; R² = 4-MeC₆H₄, 3-thienyl, 2-naphthyl, R³ = H; R²R³ = o-C₆H₄CH₂CH₂, etc.) and pyrazolo[1,5-a]quinazolines, e.g., IV. Four of the synthesized pyrazole fused compounds, including I, II, and III (R¹ = H; R² = 4-MeC₆H₄; R³ = H), showed in vitro cytotoxic activities almost comparable to the drug doxorubicin against the cervical HeLa cancer cell line and prostate DU 205 cancer cell line. In the experiment, the researchers used many compounds, for example, 1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3Application In Synthesis of 1-Ethyl-1H-pyrazol-5-amine).

1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3) belongs to pyrazole derivatives. The 1H-pyrazole provides an excellent means by which to provide the requisite hydrogen bond acceptor–donor motifs, whether as a monocyclic ring or as a fused indazole ring. 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.Application In Synthesis of 1-Ethyl-1H-pyrazol-5-amine

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

Solvatochromism of heteroaromatic compounds: VI. Comparison of the empirical and theoretical approaches to description of solvatochromism in nonspecific solvation of nitropyrazoles was written by Vokin, A. I.;Shulunova, A. M.;Aksamentova, T. N.;Es’kova, L. A.;Elokhina, V. N.;Lopyrev, V. A.;Turchaninov, V. K.. And the article was included in Russian Journal of General Chemistry (Translation of Zhurnal Obshchei Khimii) in 2001.Name: 1-Methyl-3-nitro-1H-pyrazole This article mentions the following:

The effect of nonspecific solvation on the long-wave absorption band in the UV spectra of isomeric nitropyrazoles was studied. The aprotic inert and aprotic protophilic solvents exert different spectroscopic effects. In the former solvents, the solvatochromism is mainly governed by orientation interactions, and in the latter solvents, along with the orientation interactions, the UV spectrum is appreciably influenced by the induction, polarization, and dispersion interactions, which is due to the presence of readily polarizable nonbonding electron pairs and/or a π-electron system in mols. of such solvents. In the experiment, the researchers used many compounds, for example, 1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1Name: 1-Methyl-3-nitro-1H-pyrazole).

1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1) 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 can be selectively lithiated at different carbons and subsequently react with electrophiles depending on the substitution patterns.Name: 1-Methyl-3-nitro-1H-pyrazole

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

‘On water’ highly atom economical and rapid synthesis of a novel class of 3-hydroxy-2-oxindole scaffolds under a catalyst-free and column chromatography-free protocol at room temperature was written by Thakur, Pramod B.;Meshram, Harshadas M.. And the article was included in RSC Advances in 2014.Computed Properties of C4H3F3N2O This article mentions the following:

An ‘on water’ highly atom economical and rapid protocol has been developed for the synthesis of 3-(2-pyrazolin-5-one) substituted, 3-hydroxy-2-oxindole scaffolds I (R¹ = H, C₆H₅; R² = H, Cl; R³ = F, NO₂, CH₃, Cl, H, I; R⁴ = H, Cl, CH₃; R⁵ = H, CH₃, CH₂CH₂CH₃) under catalyst-free and column chromatog.-free conditions at rt. The generality of the method has been demonstrated by screening a series of isatin electrophiles as well as 2-pyrazolin-5-one derivatives The developed method is a good example of green synthesis in which straightforward synthesis of a medicinally important 3-hydroxy-2-oxindole framework is executed by employing very mild, simple and handy procedures from readily available starting materials. In the experiment, the researchers used many compounds, for example, 3-(Trifluoromethyl)-1H-pyrazol-5(4H)-one (cas: 401-73-0Computed Properties of C4H3F3N2O).

3-(Trifluoromethyl)-1H-pyrazol-5(4H)-one (cas: 401-73-0) 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. Pyrazole rings have been used as core components of several leading non-steroidal anti-inflammatory drugs (NSAIDs) and antihypertensive drugs. It has also been found to be useful as a bifunctional ligand for metal catalysis.Computed Properties of C4H3F3N2O

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