Tag: 100-200

The preparation of 3-fluoroisonicotinic acid and related compounds was written by Roe, Arthur;Seligman, Robert B.. And the article was included in Journal of Organic Chemistry in 1955.Computed Properties of C6H6FN This article mentions the following:

To study the effect of a F atom adjacent to the CO₂H group on the antituberculostatic activity of isonicotinic acid hydrazide, 3-fluoroisonicotinic acid (I) and some related compounds are prepared 2-Amino-4-picoline (50 g.) is converted by the method of Hawkins and Roe (C.A. 44,628i) into the nitramine and allowed to rearrange to 3- and 5-nitro-2-amino-4-picoline, which are hydrolyzed to a mixture (II), m. 159°, of 3-(III) and 5-nitro-2-hydroxy-4-picoline (IV). Warming 2.5 g. IV 2.5 hrs. with 20 cc. POCl₃ gives 60.7% 2-chloro-5-nitro-4-picoline (V), b₅ 91.2°, m. 38.5-9.5°. Similarly, III gives 2-chloro-3-nitro-4-picoline (VI), m. 52-2.9°. Treating II with POCl₃ gives a mixture of V and VI which (25 g.) is hydrogenated in 20 cc. AcOH in the presence of 0.5 g. NaOAc and 10% Pd-C at 65 lb. H pressure, the mixture evaporated in vacuo, and the residue made strongly alk. and extracted with Et₂O, giving 89.5% 3-amino-4-picoline (VII), m. 104-5° (picrate, m. 177-8°). VII is converted by a modified Schiemann reaction into 4-picoline-3-diazonium fluoborate which, decomposed in boiling petr. ether (b.p. 60-90°), gives 68% 3-fluoro-4-picoline (VIII), b₇₄₈ 135.6°, n_D^27.5 1.4795 (picrate, yellow plates, m. 129-30°). Adding dropwise (3.5 hrs.) 48 g. KMnO₄ in H₂O to 17 g. VIII in 1 l. refluxing H₂O, steam distilling the mixture to remove any unchanged VIII, evaporating the filtered solution until crystallization sets in, and acidifying it with HCl gives 45% I, m. 256-7° (decomposition and sublimation). Refluxing 2 g. I 1.5 hrs. with 20 cc. SOCl₂, distilling off the excess SOCl₂, and refluxing the residue 1 hr. with EtOH gives Et 3-fluoroisonicotinate-HCl (IX.HCl), from which 83.4% IX, b₇₅₂ 215°, is obtained (picrate, long yellow needles, m. 109-10°). Refluxing 2 g. IX 5.5 hrs. with 1.5 cc. 85% N₂H₄.H₂O and 20 cc. 95% EtOH and distilling off the EtOH gives 92% I hydrazide, fine needles, m. 146.8-7.8°. IX.HCl refluxed with N₂H₄.H₂O 36 hrs. forms 3-hydroxyisonicotinic acid hydrazide. In the experiment, the researchers used many compounds, for example, 3-Fluoro-4-methylpyridine (cas: 399-88-2Computed Properties of C6H6FN).

3-Fluoro-4-methylpyridine (cas: 399-88-2) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Computed Properties of C6H6FN

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Caveat regarding the use of substituent parameters in statistical analyses of molecular properties. II. Case study: carbon-13 NMR of 2-substituted pyridines and monosubstituted benzenes was written by Cook, Iain B.. And the article was included in Australian Journal of Chemistry in 1989.Recommanded Product: 2-Phenoxypyridine This article mentions the following:

Carbon-13 NMR substituent chem. shifts of equivalent positions on monosubstituted benzenes and 2-substituted pyridines are analyzed by multiple linear regression on combinations of field, resonance, electronegatively and three polarizability parameters. The ortho and meta positions of the 2-pyridine and benzene series are poorly described by σ_F and σ_R parameters, but a much improved fit is obtained when σ_x and/or a bond polarizability parameter σ_α (C-X) are included. The mechanism of shift formation differs markedly between the two systems when the C(2), C(4), and C(6) positions on pyridine are compared with the geometrically equivalent positions on benzenes. Owing to the high degree of interdependence between the four substituent effects, quant. anal. proved to be impossible. However, use of subsets of substituents with three of the four parameters approx. orthogonal enabled the mechanism to be deduced in most cases. It is postulated that the differences between the pyridine and benzene systems arises from perturbation of the C-N bond polarity. A mechanism to explain the results is presented. In the experiment, the researchers used many compounds, for example, 2-Phenoxypyridine (cas: 4783-68-0Recommanded Product: 2-Phenoxypyridine).

2-Phenoxypyridine (cas: 4783-68-0) belongs to pyridine derivatives. Pyridine is diamagnetic and has a diamagnetic susceptibility of âˆ?8.7 × 10âˆ? cm3·molâˆ?.The molecular electric dipole moment is 2.2 debyes. The standard enthalpy of formation is 100.2 kJ·molâˆ? in the liquid phase and 140.4 kJ·molâˆ? in the gas phase. Several pyridine derivatives play important roles in biological systems. While its biosynthesis is not fully understood, nicotinic acid (vitamin B3) occurs in some bacteria, fungi, and mammals.Recommanded Product: 2-Phenoxypyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Thermal interaction of linoleic acid and its esters with valine was written by Henderson, S. K.;Nawar, W. W.. And the article was included in JAOCS, J. Am. Oil Chem. Soc. in 1981.Application In Synthesis of 4-Hexylpyridine This article mentions the following:

When linoleic acid or its esters were heated in the presence of valine, a number of products were formed. The major product was 2-pentylpyridine, which was produced by the reaction of 2,4-decadienal with ammonia. Also formed were isobutyloctanamide and isobutylinoleylamide. Addnl. products include alkylpyridines and alkylpyrrole. They can result by reaction of an aldehyde with an amine or ammonia to form a Schiff base, followed by cyclization and rearrangement to form either the pyridine ring of the pyrrole ring. In addition, a branched nitrile compound was produced which was formed by cleavage of the pyridine ring in 2-pentylpyridine. In the experiment, the researchers used many compounds, for example, 4-Hexylpyridine (cas: 27876-24-0Application In Synthesis of 4-Hexylpyridine).

4-Hexylpyridine (cas: 27876-24-0) belongs to pyridine derivatives. Pyridine’s the lone pair does not contribute to the aromatic system but importantly influences the chemical properties of pyridine, as it easily supports bond formation via an electrophilic attack. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Application In Synthesis of 4-Hexylpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Derivatives of pyridine and quinoline. LXXII. Reactivity of bromine atoms in brominated pyridines. Action of sodium phenate on 2,4,6-tribromopyridine was written by den Hertog, H. J.;de Jonge, A. P.. And the article was included in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique in 1948.COA of Formula: C11H9NO This article mentions the following:

VI (3 g.), 0.25 g. Na, and 20 g. PhOH are heated 24 hrs. in a sealed tube at 145-50°, and the contents of 3 tubes poured into 300 cc. 15% NaOH and extracted with Et₂O. Washing (NaOH) and drying (Na₂SO₄) the Et₂O give 0.7 g. mainly VI, b_0.7 110-25°; 0.9 g., b_0.9 135-45°, which, washed with alc., gives 0.5 g. undissolved VI and 2,4-dibromo-6-phenoxypyridine (X), m. 41.5-2.5°, by evaporating the filtrate; 4.5 g. X, b₁ 153-61°, m. 37-41°; and a 4th fraction, b_1.4 165-85°, which, washed with alc., gives a residue of 4-bromo-2,6-diphenoxypyridine (XI), m. 88-92°. VI (2 g.), 0.3 g. Na, and 20 g. PhOH, heated in a sealed tube 24 hrs. at 195° and poured into aqueous NaOH, give 1.3 g. (60%) XI, m. 93-4°. Similarly, 2 g. 2-bromopyridine, 0.5 g. Na, and 12 g. PhOH give 1.4 g. (70%) 2-phenoxypyridine (XII), m. 42-4° [XII and alc. picric acid give the picrate, m. 104.5-5.5° (from BuOH)]. 2,6-Dibromopyridine (XIII) (1 g.), 0.2 g. Na, and 12 g. PhOH give 1 g. crude 2,6-diphenoxypyridine (XIV), m. 60-1° after sublimation in vacuo; 1 g. 2,4-dibromopyridine, 0.5 g. Na, and 20 g. PhOH give 95-100% 2,4-diphenoxypyridine (XV), m. 87.5-8.5° (picrate, m. 140-1°, from picric acid-BuOH); and 1 g. VI, 1 g. Na, and 20 g. PhOH (36 hrs.) give 2,4,6-triphenoxypyridine (XVI), m. 79-9.5°. X (0.66 g.), 0.2 g. NaOH in alc., and 0.15 g. PdCl₂ absorb the calculated amount H in 20 min.; evaporation of the filtered solution gives, on pouring the residue into H₂O and ice-cooling, XII, m. 37-40°. VI (9 g.), 2.7 g. PhOH, 1.2 g. NaOH, and 9 cc. H₂O, heated 24 hrs. at 150° in a sealed tube, and the lower layer made strongly alk. and extracted with Et₂O, give, on drying and distilling the Et₂O, 2.2 g. VI, b_0.7 130°, and 3.5 g. semisolid, b_1.5 140-65°, which, filtered through a glass filter, gives 1.2 g. 2,6-dibromo-4-phenoxypyridine (XVII), m. 84.5-5.5°; the filtrate, cooled and filtered, gives 1.3 g. crude X, m. 33-8°. Hydrogenation of XVII as described above and petr. ether-extraction of the aqueous NaOH-diluted residue gives 4-phenoxypyridine, m. 40-3°, identical with that (m. 45.5-6.5°) prepared according to Königs and Greiner (C.A. 25, 3998); picrate, m. 171.5-2° (from alc., then BuOH). Hydrogenation of XI gives XIV, m. 59.5-61°. XIII (4 g.) and 15 cc. 40% aqueous PhONa, heated in a sealed tube 10 hrs. at 150°, give, after recrystallization from 50% alc., then petr. ether, 75-80% 2-bromo-6-phenoxypyridine, m. 86.5-7.5°. XVII (0.8 g.), 0.055 g. Na, and 15 g. PhOH (sealed tube, 195°, 24 hrs.) give, on extracting the basified mixture with Et₂O and evaporating the Et₂O, a semisolid which, filtered, gives 2-bromo-4,6-diphenoxypyridine (XVIII), m. 87-8°. Hydrogenation of XVIII gives, on evaporating the filtered solution, basifying the residue, extracting with Et₂O, distilling the Et₂O, and treating the residue in BuOH with picric acid-BuOH, the picrate, m. 141-2°, of XV. X, XI, XII, XIV, XV, XVI, XVII, and XVIII are recrystallized from petr. ether. In the experiment, the researchers used many compounds, for example, 2-Phenoxypyridine (cas: 4783-68-0COA of Formula: C11H9NO).

2-Phenoxypyridine (cas: 4783-68-0) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.COA of Formula: C11H9NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Diastereoselective Cyclization of 1,5-Dienes with the C-H Bond of Pyridine Catalyzed by a Cationic Mono(phosphinoamide) Alkyl Scandium Complex was written by Chen, Yanhui;Song, Di;Li, Jing;Hu, Xiaoyan;Bi, Xianjia;Jiang, Tao;Hou, Zhaomin. And the article was included in ChemCatChem in 2018.Name: 2-Isopropylpyridine This article mentions the following:

Novel rare-earth dialkyl complexes bearing a phosphinoamide anion and demonstrate that the combination of a mono(phosphinoamido)-ligated scandium dialkyl complex with B(C₆F₅)₃ results in an excellent catalyst for the cis-selective cyclization of 1,5-dienes with the ortho-C(sp²)-H bond of pyridines to afford a new family of pyridyl-functionalized 1,3-disubstituted cyclopentane derivatives containing monocyclic, bicyclic, spirocyclic, and heterocyclic skeletons in moderate to excellent yields with high diastereoselectivities (cis/trans up to 99:1). In the experiment, the researchers used many compounds, for example, 2-Isopropylpyridine (cas: 644-98-4Name: 2-Isopropylpyridine).

2-Isopropylpyridine (cas: 644-98-4) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Name: 2-Isopropylpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Practical and rapid construction of 2-pyridyl ketone library in continuous flow was written by Sun, Maolin;Li, Jianchang;Liang, Chaoming;Shan, Chao;Shen, Xinyuan;Cheng, Ruihua;Ma, Yueyue;Ye, Jinxing. And the article was included in Journal of Flow Chemistry in 2021.SDS of cas: 91-02-1 This article mentions the following:

Herein, a practical method for the rapid synthesis of 2-pyridyl ketone ArC(O)R [Ar = 2-pyridyl; R = Me, Ph, Bn, etc.] library in continuous flow was reported, in which the 2-lithiopyridine formed by Br/Li exchange reacts with com. available esters to obtain 2-pyridyl ketones ArC(O)R in a good yield at short reaction time. This protocol functions broadly on a variety of esters and had been applied to the synthesis of TGF-β type 1 receptor inhibitor LY580276 intermediate ArC(O)R [Ar = 6-methyl-2-pyridyl; R = (4-fluorophenyl)methyl] in an environmentally friendly method. It was rapid, reliable, and cost-efficient to afford diverse kinds of 2-pyridyl ketones ArC(O)R in the compound library. In the experiment, the researchers used many compounds, for example, Phenyl(pyridin-2-yl)methanone (cas: 91-02-1SDS of cas: 91-02-1).

Phenyl(pyridin-2-yl)methanone (cas: 91-02-1) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Reduced pyridines, namely tetrahydropyridines, dihydropyridines and piperidines, are found in numerous natural and synthetic compounds. The synthesis and reactivity of these compounds have often been driven by the fact many of these compounds have interesting and unique pharmacological properties. SDS of cas: 91-02-1

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ortho amino cyano aromatic compounds as precursor for the synthesis of some novel heterocyclic compounds was written by Rao, V. S.;Gupta, S. V. S. Arun Kumar;Reddy, B. S.. And the article was included in Heterocyclic Communications in 1999.Related Products of 823-61-0 This article mentions the following:

Pyrimidin-4(1H)-ones from 2-amino-3-cyano aromatic compounds were prepared in the presence of formic acid under strong acid catalyst. The intermediates and the final products structures were confirmed by spectral and elemental data. In the experiment, the researchers used many compounds, for example, 3,6-Dimethyl-2-pyridinamine (cas: 823-61-0Related Products of 823-61-0).

3,6-Dimethyl-2-pyridinamine (cas: 823-61-0) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Related Products of 823-61-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

A Convenient Esterification of N-Heteroarene Methanols via C-CN Bond Cleavage of Benzoyl Cyanides as Acylating Sources was written by Su, Fangyao;Zhao, Qianrui;Wang, Mengzhuo;Zhao, Mingzhang;Ren, Yihe;Zhu, Binghan;Chen, Haoran;Lai, Miao;Zhao, Mingqin. And the article was included in ChemistrySelect in 2022.Product Details of 131747-45-0 This article mentions the following:

An efficient and straightforward methodol. for the esterification of various N-heteroarene methanols using benzoyl cyanides as acylating sources through a simply mixing conditions has been reported. The acyl groups were in-situ generated via chemoselective C-CN bond cleavage to give the N-heteroarenemethyl esters. This process features in readily accessible starting materials and offers an easy operational procedure, and broad substrate scope with excellent selectivity. In the experiment, the researchers used many compounds, for example, (4-Bromopyridin-2-yl)methanol (cas: 131747-45-0Product Details of 131747-45-0).

(4-Bromopyridin-2-yl)methanol (cas: 131747-45-0) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ·molâˆ? in pyridine vs. 150 kJ·molâˆ? in benzene). Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Product Details of 131747-45-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Flupirtine and retigabine as templates for ligand-based drug design of K_V7.2/3 activators was written by Surur, Abdrrahman S.;Bock, Christian;Beirow, Kristin;Wurm, Konrad;Schulig, Lukas;Kindermann, Markus K.;Siegmund, Werner;Bednarski, Patrick J.;Link, Andreas. And the article was included in Organic & Biomolecular Chemistry in 2019.Synthetic Route of C6H6ClN3O2 This article mentions the following:

Drug induced liver injury (DILI) and tissue discoloration led to the recent discontinuation of the therapeutic use of the closely related drugs flupirtine and retigabine, resp. Experience gained with these drugs strongly suggests that heterotetramer, voltage-gated potassium channels 2 and 3 (K_V7.2/3) are valid targets for effective treatment of pain and epilepsy. Because the adverse effects are not related to the mechanism of action, it appears promising to investigate chem. modifications of these clin. validated, drug-like leads. In the present retro-metabolic drug design study, a series of 43 compounds were synthesized and characterized with regard to K_V7.2/3 opening activity and efficacy. The most active compound I displays excellent potency (EC₅₀ = 4 nM) and efficacy (154%) as a K_V7.2/3 opener. Limited aqueous solubility hampered toxicity testing at concentrations higher than 63 μM, but this concentration was nontoxic to two hepatocellular cell lines (HEP-G2 and TAMH) in culture. The slightly less active but more soluble compound II (EC₅₀ = 11 nM, efficacy 111%) showed an improved toxicity/activity ratio compared to flupirtine by three orders of magnitude and represents an attractive lead structure for the development of safer analgesics and antiepileptics. In the experiment, the researchers used many compounds, for example, 6-Chloro-5-methyl-3-nitropyridin-2-amine (cas: 202217-19-4Synthetic Route of C6H6ClN3O2).

6-Chloro-5-methyl-3-nitropyridin-2-amine (cas: 202217-19-4) belongs to pyridine derivatives. Pyridine is diamagnetic and has a diamagnetic susceptibility of âˆ?8.7 × 10âˆ? cm3·molâˆ?.The molecular electric dipole moment is 2.2 debyes. The standard enthalpy of formation is 100.2 kJ·molâˆ? in the liquid phase and 140.4 kJ·molâˆ? in the gas phase. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Synthetic Route of C6H6ClN3O2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Molecular energetics of alkyl substituted pyridine N-oxides was written by Cabral, Joana I. T. A.;Monteiro, Ricardo A. R.;Rocha, Marisa A. A.;Santos, Luis M. N. B. F.;Acree, William E. Jr.;Ribeiro da Silva, Maria D. M. C.. And the article was included in Journal of Thermal Analysis and Calorimetry in 2010.Computed Properties of C7H9NO This article mentions the following:

The standard (p° = 0.1 MPa) energies of combustion in oxygen, at T = 298.15 K, for the solid compounds 2-methylpyridine-N-oxide (2-MePyNO), 3-methylpyridine-N-oxide (3-MePyNO), and 3,5-dimethylpyridine-N-oxide (3,5-DMePyNO) were measured by static-bomb calorimetry, from which the resp. standard molar enthalpies of formation in the condensed phase were derived. The standard molar enthalpies of sublimation, at the same temperature, were measured by Calvet microcalorimetry. From the standard molar enthalpy of formation in gaseous phase, the molar dissociation enthalpies of the N-O bonds were derived and compared with values of the dissociation enthalpies of other N-O bonds available for other pyridine-N-oxide derivatives In the experiment, the researchers used many compounds, for example, 3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8Computed Properties of C7H9NO).

3,5-Dimethylpyridine 1-oxide (cas: 3718-65-8) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. Reduced pyridines, namely tetrahydropyridines, dihydropyridines and piperidines, are found in numerous natural and synthetic compounds. The synthesis and reactivity of these compounds have often been driven by the fact many of these compounds have interesting and unique pharmacological properties. Computed Properties of C7H9NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem