Tag: 100-200

Solvatochromism of heteroaromatic compounds: XXVIII. Factors affecting the nonspecific solvatochromic effect in the UV spectra of aromatic nitro compounds in aprotic protophilic solvents was written by Vokin, A. I.;Shulunova, A. M.;Aksamentova, T. N.;Bozhenkov, G. V.;Turchaninov, V. K.. And the article was included in Russian Journal of General Chemistry in 2006.Related Products of 54210-32-1 This article mentions the following:

Examination of the UV spectra of a large series of solvatochromic indicators of the general formula 1-X-4-NO₂-C₆H₄ in aprotic solvents confirmed the proportionality between the dipole moments of these compounds in the ground (μ_g) and first electronically excited (¹A₁, μ_e) states: μ_e = r_μμ_g. The coefficient r_μ was determined by applying the equation of the Bakhshiev-Bilot-Kawski solvatochromism theory both to nonspecifically solvated mols. and to their H complexes with aprotic protophilic solvents. An anisotropy of the electron redistribution was revealed for low-symmetry 1-substituted 2,4-dinitrobenzenes. The r_μ value obtained allowed the calculation of the Kamlet-Taft empirical solvatochromic parameter π* on the basis of generalized characteristics of the solvent. In the experiment, the researchers used many compounds, for example, 1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1Related Products 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. 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.Related Products of 54210-32-1

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

Selective palladium-catalyzed direct C-H arylation of unsubstituted N-protected pyrazoles was written by Kumpulainen, Esa T. T.;Pohjakallio, Antti. And the article was included in Advanced Synthesis & Catalysis in 2014.Recommanded Product: 3-(1H-Pyrazol-3-yl)pyridine This article mentions the following:

A highly selective C-5 arylation of N-dimethylaminosulfamoyl-protected pyrazole with aryl bromides is catalyzed by 2-5 mol% palladium in the presence of triphenylphosphine ligand and carboxylic acid additive. Selectivities up to 45:1 (C-5:C-4) can be achieved by running the reaction in non-polar solvents. A thorough study of scope and limitations shows good general tolerance of aryl bromide substitution. However, limitations on tolerance of ortho-substitution and protic functional groups were established. Together with a telescoped deprotection step this method presents a viable alternative for the synthesis of C-3 arylated pyrazole building blocks. © 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. In the experiment, the researchers used many compounds, for example, 3-(1H-Pyrazol-3-yl)pyridine (cas: 45887-08-9Recommanded Product: 3-(1H-Pyrazol-3-yl)pyridine).

3-(1H-Pyrazol-3-yl)pyridine (cas: 45887-08-9) 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. Pyrazole the presence of this nucleus in pharmacological agents of diverse therapeutic categories such as celecoxib, a potent anti-inflammatory, the antidepressant agent fezolamide have proved the pharmacological potential of the pyrazole moiety. Recommanded Product: 3-(1H-Pyrazol-3-yl)pyridine

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

Unambiguous synthesis of 4,7-dihydro-4-oxo-1H-pyrazolo[3,4-b]pyridine – further comments on the “(N-C) rearrangement” of [2-(alkoxycarbonyl)vinylamino]pyrazoles was written by Dorn, Helmut;Ozegowski, Ruediger. And the article was included in Journal fuer Praktische Chemie (Leipzig) in 1982.Recommanded Product: 3528-58-3 This article mentions the following:

Successive decarboxylation of pyrazolopyridine I and debenzylation of II (R¹ = CH₂Ph, R² = H) with Na in NH₃(l) gave the title compound II (R¹ = R² = H). The product from 3-aminopyrazole and HCCCO₂Me, formerly described as II (R¹ = R² = H), is the 6-oxo isomer III (R¹ = R² = H). Debenzylation of II (R¹ = CH₂Ph, R² = H) and analogs with SeO₂ is only possible if the position α to the C:O is blocked; otherwise, selenides of type IV are formed. Cyclizing pyrazoles V (R¹ = R² = H, R¹ = CH₂Ph, R² = H, Me; R³ = Me, Et) in acidic media with catalytic amounts the corresponding aminopyrazoles gave pyrazolopyridines III via pyrazoles VI, i.e., via products of a N-C rearrangement, whereas thermal cyclization of V gave II (R¹,R² as above and also R¹ = CH₂Ph, R² = Me). In the experiment, the researchers used many compounds, for example, 1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3Recommanded Product: 3528-58-3).

1-Ethyl-1H-pyrazol-5-amine (cas: 3528-58-3) 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.Recommanded Product: 3528-58-3

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

Extraction and analysis on the aromatic components of Pu-erh ripe tea and raw tea was written by Hong, Tao;Huang, Zun-xi;Li, Jun-jun;Tang, Xiang-hua;Mu, Yue-lin;Xu, Bo. And the article was included in Chaye Kexue in 2010.Name: 1-Ethyl-1H-pyrazol-5-amine This article mentions the following:

The aromatic components from Pu-erh ripe and raw tea which storage for different years extracted by methylene chloride and Et ether through vacuum distillation extraction, and then investigated by gas chromatog.-mass spectrometry. It showed that the aromatic compounds extracted by methylene chloride were more than Et ether no matter they were ripe tea or raw tea. Those compounds including hydrocarbons, heterocyclic oxygen compounds, nitrogenous compounds, ketones were extracted more by methylene chloride than those extracted by Et ether. However, more esters and phenolic compounds were extracted by Et ether. The contents of benzothiazole and caffeine increased during the process of ripe tea’s storage, but the contents of phthalic acid, iso-Bu octyl ester and 1,2,4-trimethoxybenzene were decreased. The contents of 5-amino-1-ethylpyrazole, N-phenyl-1-naphthalenamine, 1,2,3-trimethoxybenzene and phthalic acid-iso-butyl-octyl ester were increased during the storing process of raw tea, but the contents of trans-squalene, linalool, beta-iso-Me ionone and caffeine were decreased. At the same time, there were many aromatic compounds of heterocyclic oxygen compounds in ripe tea. The main components of these 10 heterocyclic oxygen compounds included 1,2,3-trimethoxybenzene. The contents of alcs. aromatic components in raw tea, such as 1-octen-3-yl, linalool, cyclohexanol, 2,6-dimethylcyclohexanol, Ph Et alc. and cedrol. 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. Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. 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.Name: 1-Ethyl-1H-pyrazol-5-amine

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

Quantum chemical studies on N-donors based-pyrazole compounds as corrosion inhibitors for steel in acidic media was written by Attayibat, Ahmed;Touzani, Rachid;Radi, Smaail;El Kadiri, Sghir;Sari, Souad;Abdelli, Imene;Ghalem, Said. And the article was included in Asian Journal of Chemistry in 2009.Recommanded Product: 19959-77-4 This article mentions the following:

In this study, some possible relationship between the exptl. inhibition corrosion in acidic media and the theor. energy calculations for four series of compounds containing pyrazoles: (A) the first series of compounds, comprises only one pyrazole ring, (B) the second series has two pyrazoles (bipyrazole), (C) the third one contains one pyrazole and one pyridine (pyridyl pyrazole) and (D) the last series concerns tripodal pyrazoles, has presented. These sets of compounds have been tested for their corrosion inhibition properties of steel in low concentration of hydrochloric acid medium. For these compounds, DFT method studies have been performed. They were based on (E_HOMO), (E_LUMO) and the difference (E_LUMO-E_HOMO). The correlation between these two parameters (theor. and exptl.) was shown to be in good agreement for some cases. In the experiment, the researchers used many compounds, for example, 2-(5-Methyl-1H-pyrazol-3-yl)pyridine (cas: 19959-77-4Recommanded Product: 19959-77-4).

2-(5-Methyl-1H-pyrazol-3-yl)pyridine (cas: 19959-77-4) 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. Pyrazole the presence of this nucleus in pharmacological agents of diverse therapeutic categories such as celecoxib, a potent anti-inflammatory, the antidepressant agent fezolamide have proved the pharmacological potential of the pyrazole moiety. Recommanded Product: 19959-77-4

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

Theoretical study on structures and detonation performances for nitro derivatives of pyrazole by density functional theory was written by Yi, Jian-hong;Hu, Shuang-qi;Liu, Sheng-nan;Cao, Duan-lin;Ren, Jun. And the article was included in Hanneng Cailiao in 2010.Electric Literature of C4H5N3O2 This article mentions the following:

Twenty-four nitropyzarole compounds and their derivatives were investigated by d. functional theory. Their optimized geometries and electronic structures were calculated at the B3LYP/6-311G(d,p) level. Optimized geometries of these compounds show that they have no imaginary frequencies, and they are stable on the potential energy surface. The heat capacity and enthalpy of some typical compounds at different temperatures were obtained by statistic thermodn., and isodesmic reactions were designed for calculating standard enthalpies of formation for the derivatives of nitropyzarole. The average molar volume and theor. d. were estimated using the Monte-Carlo method based on 0.001 e · bohr^-3 d. space. Furthermore, the detonation velocity and pressure of the derivatives were estimated by the Kamlet-Jacbos equation. Results show that the ring of pyrazole has some aromaticity and the detonation velocities of these compounds are between 6.42 and 9.00 km · s^-1. Detonation performances of these compounds show that they are very good candidates for energetic materials. In the experiment, the researchers used many compounds, for example, 1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1Electric Literature of C4H5N3O2).

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

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

Basicity of nitropyrazoles and their simultaneous spectrophotometric determination was written by Dumanovic, D.;Ciric, J.;Muk, A.;Nikolic, V.. And the article was included in Talanta in 1975.Category: pyrazoles-derivatives This article mentions the following:

Uv spectra of nitropyrazoles showed that NO2 shifted the absorption maximum of the neutral mols. and the protonated ionic forms to longer wavelengths by 50-70 nm and 10-30 nm, resp. The basicities of the compounds were compared with those of nitroimidazoles and the NO2 group effects and ortho group effect were determined The effect of NO2 on protonation constants was greater when NO2 was close to the pyridine N. The results indicate that simultaneous spectrophotometric determination of nitropyrazoles is possible. In the experiment, the researchers used many compounds, for example, 1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1Category: pyrazoles-derivatives).

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. 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.Category: pyrazoles-derivatives

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

Basicity of C-substituted pyrazoles in the gas phase: an experimental (ICR) and theoretical study was written by Abboud, J. L. M.;Cabildo, P.;Canada, T.;Catalan, J.;Claramunt, R. M.;De Paz, J. L. G.;Elguero, J.;Homan, H.;Notario, R.. And the article was included in Journal of Organic Chemistry in 1992.Application of 54210-32-1 This article mentions the following:

The exptl. gas-phase proton affinities (PAs) of 32 N-H and N-Me pyrazoles have been determined by means of Fourier Transform Ion Cyclotron Resonance Spectroscopy (FTICR). Previously reported PAs for 12 C-methyl-substituted pyrazoles, in total provide a set of 57 data (counting each tautomer sep.). The remarkably large spread of PAs, ca. 55 kcal.mol^-1, makes this set most suitable for structural analyses. In a few cases, ab initio 6-31G//6-31G protonation energies were calculated and found to be linearly related to the exptl. PAs to a very high degree of precision. A simple additive model of substituent effects on PAs (including substitutions at positions 3, 4, and 5) was found to hold, even for very crowded derivatives such as 1,4-dimethyl-3,5-di-tert-butylpyrazoles . The only significant interaction appears between Ph groups at positions 3 and 5. The statistically averaged substituent effects on PAs were successfully analyzed in terms of polarizability and field and resonance contributions, according to the Taft-Topsom model. Both positions 3 and 5 behave in a way similar to that of position 2 in the pyridines. From this interesting result it follows that, with the exception of 3-aminopyrazole, the tautomerism of pyrazoles is not very dependent of the nature of the 3(5)-substituent. In the experiment, the researchers used many compounds, for example, 1-Methyl-3-nitro-1H-pyrazole (cas: 54210-32-1Application of 54210-32-1).

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

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

Synthesis and characterization of some symmetrical substituted 1-(2-chloroethyl)pyrazole-based chalcogenides was written by Pundir, S.;Mehta, S. K.;Mobin, S. M.;Bhasin, K. K.. And the article was included in Indian Journal of Heterocyclic Chemistry in 2017.Application In Synthesis of 4-Chloro-3,5-dimethyl-1H-pyrazole This article mentions the following:

The synthesis of some sym. substituted 1-(2-chloroethyl) pyrazole-based dichalcogenides I [X = H, Cl, Br, CHO; R = S, Se, Te] and monochalcogenides II [X = H, Cl] by reacting different 3,4,5-trisubstituted 1-(2-chloroethyl) pyrazole derivatives with in situ prepared Na₂E₂ (E = S, Se, Te) and sodium hydrogen selenide, resp. X-ray crystal structure determination of 1,2-bis (2-(4-bromo-3,5-dimethyl-1H-pyrazol-1-yl)ethyl)diselane I [X = Br; R = Se] revealed intermol. Se·N·H interactions between two mols. In the experiment, the researchers used many compounds, for example, 4-Chloro-3,5-dimethyl-1H-pyrazole (cas: 15953-73-8Application In Synthesis of 4-Chloro-3,5-dimethyl-1H-pyrazole).

4-Chloro-3,5-dimethyl-1H-pyrazole (cas: 15953-73-8) 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 4-Chloro-3,5-dimethyl-1H-pyrazole

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

Silica-sulfuric acid-catalyzed nitrodeiodination of iodopyrazoles was written by Ravi, P.;Gore, Girish M.;Sikder, Arun K.;Tewari, Surya P.. And the article was included in Synthetic Communications in 2012.Related Products of 5334-39-4 This article mentions the following:

The synthesis of nitropyrazoles in good to excellent yields from iodopyrazoles over silica-sulfuric acid catalyst for the first time was reported. The present procedure require less acid, offers a simplified workup procedure, and may be applied for the nitration of a wide variety of iodoazoles in drug and pharmaceutical industries. In the experiment, the researchers used many compounds, for example, 3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4Related Products of 5334-39-4).

3-Methyl-4-nitro-1H-pyrazole (cas: 5334-39-4) 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. 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.Related Products of 5334-39-4

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