Category: pyrazoles-derivatives

Graton, Jerome published the artcileHydrogen-Bond Accepting Properties of New Heteroaromatic Ring Chemical Motifs: A Theoretical Study, Recommanded Product: 1-Methylpyrazole, the publication is Journal of Chemical Information and Modeling (2016), 56(2), 322-334, database is CAplus and MEDLINE.

The prediction of hydrogen-bond (H-bond) acceptor ability is crucial in drug design. This important property is quantified in a large pK_BHX database of consistently measured values. We aim to expand the chem. diversity of the studied H-bond acceptors and to increase the range of H-bond strength considered. Two quantum chem. descriptors are contrasted, called ΔE(H) (the change in the energy of a topol. hydrogen atom upon complexation) and V_min (the local min. in the electrostatic potential on the H-bond accepting site). We performed a systematic anal. of the correlations between pK_BHX and V_min for an initial set of 106 compounds (including O- and N-containing subsets, as well as compounds including sulfur, chlorine, and π-bases). Correlations improve for family dependent subsets, and after outlier treatment, a set of 90 compounds was used to set up a linear equation to predict pK_BHX from V_min. This equation and a previously published equation, to predict pK_BHX from ΔE(H), were used to predict the pK_BHX values for 22 potentially biol. active heteroaromatic ring compounds, among which several structures still remain exptl. unavailable. H-Bond basicity of sp² nitrogen sites were consistently predicted with both descriptors. A worse agreement was found with carbonyl acceptor sites, with the stronger deviations observed for the lactam groups. It was shown that secondary interactions involving the neighboring NH group were influencing the results. Substitution of the NH group with an NMe group resulted in an improved consistency from both V_min and ΔE(H) predictions, the latter being more prominently affected by the Me substitution. Both approaches appear as efficient procedures for the H-bond ability prediction of novel heteroaromatic rings. Nevertheless, the ΔE(H) parameter presents slight chem. structure limitations and requires more detailed H-bond structure investigations.

Journal of Chemical Information and Modeling published new progress about 930-36-9. 930-36-9 belongs to pyrazoles-derivatives, auxiliary class Pyrazole, name is 1-Methylpyrazole, and the molecular formula is C4H6N2, Recommanded Product: 1-Methylpyrazole.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics

Thach, Thi-Dan published the artcileSynthesis of sulfonamides bearing 1,3,5-triarylpyrazoline and 4-thiazolidinone moieties as novel antimicrobial agents, HPLC of Formula: 71203-35-5, the publication is Journal of the Serbian Chemical Society (2020), 85(2), 155-162, database is CAplus.

Two series of sulfonamides were synthesized from 4-hydrazinylbenzenesulfonamide as the key starting material. 1,3,5-triarylpyrazoline sulfonamides I [R = H, F, MeO; Ar = Ph, 4-MeC₆H₄, 2-HOC₆H₄, 4-MeOC₆H₄] were obtained by cyclocondensation of various chalcones in 53-64% yields, while 4-thiazolidinone derivatives II [Ar¹ = Ph, 4-MeC₆H₄, 2-HOC₆H₄, 4-ClC₆H₄, 4-MeOC₆H₄] were synthesized by cyclocondensation between mercaptoacetic acid and different phenylhydrazones in 43-62% yields. The synthesized compounds were characterized based on FTIR, ¹H-NMR, ¹³C-NMR and HRMS data. The sulfonamides were evaluated for their in vitro antimicrobial activities against four bacterial strains (E. coli, P. aeruginosa, B. subtillis and S aureus), two filamentous fungal strains (A. niger and F. oxysporum) and two yeast strains (C. albicans and S. cerevisiae). Seven pyrazolines, 2a-c and 2e-h, exhibited significant inhibition of different microbial strains. Among them, compound 2b displayed good antifungal activity against A. niger (MIC value at 12.5μg mL^-1) over the reference drug.

Journal of the Serbian Chemical Society published new progress about 71203-35-5. 71203-35-5 belongs to pyrazoles-derivatives, auxiliary class GPCR/G Protein,Ras, name is 4-(5-(4-Methoxyphenyl)-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)benzenesulfonamide, and the molecular formula is C9H8O4, HPLC of Formula: 71203-35-5.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics

Cox, Paul A. published the artcileProtodeboronation of Heteroaromatic, Vinyl, and Cyclopropyl Boronic Acids: pH-Rate Profiles, Autocatalysis, and Disproportionation, HPLC of Formula: 724710-02-5, the publication is Journal of the American Chemical Society (2016), 138(29), 9145-9157, database is CAplus and MEDLINE.

PH-rate profiles for aqueous-organic protodeboronation of 18 boronic acids, many widely viewed as unstable, have been studied by NMR and DFT. Rates were pH-dependent, and varied substantially between the boronic acids, with rate maxima that varied over 6 orders of magnitude. A mechanistic model containing five general pathways (k₁-k₅) has been developed, and together with input of [B]_tot, K_W, K_a, and K_aH, the protodeboronation kinetics can be correlated as a function of pH (1-13) for all 18 species. Cyclopropyl and vinyl boronic acids undergo very slow protodeboronation, as do 3- and 4-pyridyl boronic acids (t_0.5 > 1 wk, pH 12, 70 °C). In contrast, 2-pyridyl and 5-thiazolyl boronic acids undergo rapid protodeboronation (t_0.5 ≈ 25-50 s, pH 7, 70 °C), via fragmentation of zwitterionic intermediates. Lewis acid additives (e.g., Cu, Zn salts) can attenuate (2-pyridyl) or accelerate (5-thiazolyl and 5-pyrazolyl) fragmentation. Two addnl. processes compete when the boronic acid and the boronate are present in sufficient proportions (pH = pK_a ± 1.6): (i) self-/autocatalysis and (ii) sequential disproportionations of boronic acid to borinic acid and borane.

Journal of the American Chemical Society published new progress about 724710-02-5. 724710-02-5 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Boronic acid and ester,Pyrazole,Boronic Acids,Boronic acid and ester, name is (1H-Pyrazol-5-yl)boronic acid, and the molecular formula is C3H5BN2O2, HPLC of Formula: 724710-02-5.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics

Cox, Paul A. published the artcileProtodeboronation of Heteroaromatic, Vinyl, and Cyclopropyl Boronic Acids: pH-Rate Profiles, Autocatalysis, and Disproportionation, Quality Control of 763120-58-7, the publication is Journal of the American Chemical Society (2016), 138(29), 9145-9157, database is CAplus and MEDLINE.

PH-rate profiles for aqueous-organic protodeboronation of 18 boronic acids, many widely viewed as unstable, have been studied by NMR and DFT. Rates were pH-dependent, and varied substantially between the boronic acids, with rate maxima that varied over 6 orders of magnitude. A mechanistic model containing five general pathways (k₁-k₅) has been developed, and together with input of [B]_tot, K_W, K_a, and K_aH, the protodeboronation kinetics can be correlated as a function of pH (1-13) for all 18 species. Cyclopropyl and vinyl boronic acids undergo very slow protodeboronation, as do 3- and 4-pyridyl boronic acids (t_0.5 > 1 wk, pH 12, 70 °C). In contrast, 2-pyridyl and 5-thiazolyl boronic acids undergo rapid protodeboronation (t_0.5 ≈ 25-50 s, pH 7, 70 °C), via fragmentation of zwitterionic intermediates. Lewis acid additives (e.g., Cu, Zn salts) can attenuate (2-pyridyl) or accelerate (5-thiazolyl and 5-pyrazolyl) fragmentation. Two addnl. processes compete when the boronic acid and the boronate are present in sufficient proportions (pH = pK_a ± 1.6): (i) self-/autocatalysis and (ii) sequential disproportionations of boronic acid to borinic acid and borane.

Journal of the American Chemical Society published new progress about 763120-58-7. 763120-58-7 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Boronic acid and ester,Boronic Acids,Boronic acid and ester, name is 1H-Pyrazole-4-boronic acid, and the molecular formula is C3H5BN2O2, Quality Control of 763120-58-7.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics

Turanov, Alexander N. published the artcileAdsorption of lanthanides and scandium ions by silica sol-gel material doped with novel bifunctional ionic liquid, trioctylmethylammonium 1-phenyl-3-methyl-4-benzoyl-5-onate, Computed Properties of 4551-69-3, the publication is Journal of Environmental Chemical Engineering (2016), 4(4_Part_A), 3788-3796, database is CAplus.

Sol-gel processed silica doped with a novel bifunctional ionic liquid, trioctylmethylammonium 1-phenyl-3-methyl-4-benzoylpyrazol-5-onate ([A336]⁺[L]^–), was prepared and used as a sorbent for recovery and separation of scandium and lanthanides from nitric acid solutions The effect of HNO₃ concentration in the aqueous phase on the adsorption of microquantities of Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu is considered. A significant synergistic effect was observed for scandium and lanthanide adsorption from aqueous solutions Sc(III) is sorbed from aqueous solutions much better than lanthanides(III) and separation of Sc(III) from lanthanides(III) can be achieved by simple adjusting acidity of the aqueous phase. The efficiency of lanthanide(III) adsorption from low-concentration HNO₃ solutions increases with an increasing at. number The process of lanthanide(III) adsorption is exothermic, spontaneous and follows a pseudo-second-order kinetic model. The potentialities of the doped silica material for the preconcentration of lanthanides(III) and Sc(III) from nitrate solutions are demonstrated.

Journal of Environmental Chemical Engineering published new progress about 4551-69-3. 4551-69-3 belongs to pyrazoles-derivatives, auxiliary class Benzenes, name is 4-Benzoyl-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, and the molecular formula is C10H20O2, Computed Properties of 4551-69-3.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics

Turanov, Alexander Nikolaevich published the artcileSynergistic solvent extraction of lanthanides(III) with mixtures of 4-benzoyl-3-methyl-1-phenyl-5-pyrazolone and phosphoryl-containing podands, Recommanded Product: 4-Benzoyl-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, the publication is Acta Chimica Slovenica (2020), 67(1), 246-252, database is CAplus and MEDLINE.

The solvent extraction of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu from weak acidic chloride solutions into an organic phase containing 4-benzoyl-3-methyl-1-phenyl-5-pyrazolone (HP) and phosphoryl-containing podands (L) has been studied. A considerable synergistic effect was observed in the presence of neutral ligands L in the organic phase containing HP. The stoichiometry of the Ln(III) extracted species was determined by slope anal. and the equilibrium constants were calculated It was found that the lanthanide(III) ions are extracted with mixtures of HP and neutral ligands in toluene from weak acidic solutions as LnLP3 complexes.

Acta Chimica Slovenica published new progress about 4551-69-3. 4551-69-3 belongs to pyrazoles-derivatives, auxiliary class Benzenes, name is 4-Benzoyl-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, and the molecular formula is C10H20O2, Recommanded Product: 4-Benzoyl-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics

Alvarez, Eva Maria published the artcileLate-Stage Heteroarylation of Hetero(aryl)sulfonium Salts Activated by α-Amino Alkyl Radicals, Application of 1-Methylpyrazole, the publication is Angewandte Chemie, International Edition (2021), 60(24), 13609-13613, database is CAplus and MEDLINE.

We report a late-stage heteroarylation of aryl sulfonium salts through activation with α-amino alkyl radicals in a mechanistically distinct approach from previously reported halogen-atom transfer (XAT). The new mode of activation of aryl sulfonium salts proceeds in the absence of light and photoredox catalysts, engaging a wide range of heteroarenes. Furthermore, we demonstrate the applicability of this methodol. in synthetically useful cross-coupling transformations.

Angewandte Chemie, International Edition published new progress about 930-36-9. 930-36-9 belongs to pyrazoles-derivatives, auxiliary class Pyrazole, name is 1-Methylpyrazole, and the molecular formula is C4H6N2, Application of 1-Methylpyrazole.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics

Songsichan, T. published the artcileThiocyanation of Pyrazoles Using KSCN/K₂S₂O₈ Combination, Synthetic Route of 930-36-9, the publication is SynOpen (2018), 2(1), 0006-0016, database is CAplus.

A convenient and practical thiocyanation of pyrazoles employed a combination of KSCN and K₂S₂O₈ in DMSO (DMSO) was reported. The salient features of the present reaction included environmentally benign reagents, solvents and simple operation. The reaction showed wide functional group tolerance and gave moderate to excellent yields.

SynOpen published new progress about 930-36-9. 930-36-9 belongs to pyrazoles-derivatives, auxiliary class Pyrazole, name is 1-Methylpyrazole, and the molecular formula is C5H6BNO2, Synthetic Route of 930-36-9.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics

Keyari, Charles M. published the artcileSynthesis of New Quinolinequinone Derivatives and Preliminary Exploration of their Cytotoxic Properties, Application of 1H-Pyrazole-4-boronic acid, the publication is Journal of Medicinal Chemistry (2013), 56(10), 3806-3819, database is CAplus and MEDLINE.

A series of 7-amino- and 7-acetamidoquinoline-5,8-diones with aryl substituents at the 2-position were synthesized, characterized, and evaluated as potential NAD(P)H:quinone oxidoreductase (NQO1)-directed antitumor agents. The synthesis of lavendamycin analogs is illustrated. Metabolism studies demonstrated that 7-amino analogs were generally better substrates for NQO1 than 7-amido analogs, as were compounds with smaller heteroaromatic substituents at the C-2 position. Surprisingly, only two compounds, 7-acetamido-2-(8′-quinolinyl)quinoline-5,8-dione and 7-amino-2-(2-pyridinyl)quinoline-5,8-dione, showed selective cytotoxicity toward the NQO1-expressing MDA468-NQ16 breast cancer cells vs. the NQO1-null MDA468-WT cells. For all other compounds, NQO1 protected against quinoline-5,8-dione cytotoxicity. Compound I showed potent activity against human breast cancer cells expressing or not expressing NQO1, with resp. IC₅₀ values of 190 nM and 140 nM and a low NQO1-mediated reduction rate, which suggests that the mode of action of I differs from that of lavendamycin and involves an unidentified target(s).

Journal of Medicinal Chemistry published new progress about 763120-58-7. 763120-58-7 belongs to pyrazoles-derivatives, auxiliary class Pyrazole,Boronic acid and ester,Boronic Acids,Boronic acid and ester, name is 1H-Pyrazole-4-boronic acid, and the molecular formula is C3H5BN2O2, Application of 1H-Pyrazole-4-boronic acid.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics

Orazbayeva, Dina published the artcileDetermination of transformation products of unsymmetrical dimethylhydrazine in water using vacuum-assisted headspace solid-phase microextraction, Application of 1-Methylpyrazole, the publication is Journal of Chromatography A (2018), 30-36, database is CAplus and MEDLINE.

A new, sensitive and simple method based on vacuum-assisted headspace solid-phase microextraction (Vac-HSSPME) followed by gas chromatog.-mass-spectrometry (GC-MS), is proposed for the quantification of rocket fuel unsym. dimethylhydrazine (UDMH) transformation products in water samples. The target transformation products were: pyrazine, 1-methyl-1H-pyrazole, N-nitrosodimethylamine, N,N-dimethylformamide, 1-methyl-1H-1,2,4-triazole, 1-methyl-imidazole and 1H-pyrazole. For these analytes and within shorter sampling times, Vac-HSSPME yielded detection limits (0.5-100 ng L^-1) 3-10 times lower than those reported for regular HSSPME. Vac-HSSPME sampling for 30 min at 50 °C yielded the best combination of analyte responses and their standard deviations (<15%). 1-Formyl-2,2-dimethylhydrazine and formamide were discarded because of the poor precision and accuracy when using Vac-HSSPME. The recoveries for the rest of the analytes ranged between 80 and 119%. The modified Mininert valve and Thermogreen septum could be used for automated extraction as it ensured stable analyte signals even after long waiting times (>24 h). Finally, multiple Vac-HSSME proved to be an efficient tool for controlling the matrix effect and quantifying UDMH transformation products.

Journal of Chromatography A published new progress about 930-36-9. 930-36-9 belongs to pyrazoles-derivatives, auxiliary class Pyrazole, name is 1-Methylpyrazole, and the molecular formula is C4H6N2, Application of 1-Methylpyrazole.

Referemce:
https://en.wikipedia.org/wiki/Pyrazole,
Pyrazoles – an overview | ScienceDirect Topics