Month: February 2023

Methylpyridine derivatives. I. Synthesis of 4-substituted 3-picolines was written by Suzuki, Yasuyuki. And the article was included in Pharmaceutical Bulletin in 1957.Synthetic Route of C7H6N2 This article mentions the following:

The HCl salt of 3-picoline 1-oxide (16.5 g.) refluxed 5 h. with 30 cc. POCl₃ in 30 cc. CHCl₃, cooled, poured into ice H₂O, the aqueous layer made alk. with Na₂CO₃, steam-distilled, the distillate saturated with NaCl, extracted with ether, and the extract distilled in vacuo gave 35.5% liquid (I), b₃₀ 77-80闂? and 28.3% liquid (II), b₃₀ 81-92闂? I (1 g.) yielded 2.24 g. picrate, m. 152-3闂? of the 4-Cl derivative (III) of 3-picoline (IV), identical with the picrate of deoxygenated 4-chloro-3-picoline 1-oxide (Itai and Ogura, C.A. 50, 1808g). II (2 g.) converted to the HO derivative by the method of Ochiai, et al. (C.A. 50, 991a), redistilled in vacuo, and chromatographed over Al₂O₃ yielded 0.46 g. 2-HO derivative of IV, m. 139-41闂?(picrate, m. 158-60闂? (cf. Seide, C.A. 19, 518), 0.3 g. 6-HO derivative of IV, m. 181-3闂?(picrate, m. 147-8闂? (cf. Bradlow and Vander Werf, C.A. 43, 9069b), and a small amount of 4-HO derivative of IV, b₂ 190-2闂? m. 96-8闂?(picrate, m. 205-6闂? (cf. Clemo and Swan, C.A. 42, 4581d). Therefore, II was a mixture of 2-, 4-, and 6-Cl derivatives of IV. III (25.7 g.) treated according to Ochiai and Suzuki (C.A. 50, 1015g) yielded 10.2 g. 4-cyano derivative (V) of IV, b₈₀ 130-2闂? m. 50-2闂?(picrate, m. 154-6闂?. V (4 g.) added dropwise in the cold to the Grignard reagent from 17.3 g. PhBr, 2.6 g. Mg, 50 cc. absolute ether, and a trace of iodine, stirred an addnl. 30 min. at room temperature, the ether evaporated, the residue refluxed 2-3 h. with 50 cc. dry PhMe, cooled, saturated NH₄Cl solution added, the organic layer extracted with 10% HCl, and the acid extract made alk. and extracted with ether yielded 4.38 g. 4-Bz derivative of IV, b₃ 140-3闂? picrate, m. 178-80闂? V (0.5 g.) refluxed 3 h. on a H₂O bath with 0.75 g. NaOH in 30 cc. 70% EtOH and worked up as usual yielded 0.3 g. 4-HO₂C derivative of IV (3-methylisonicotinic acid), m. 234-6闂? Et ester (0.91 g. from 1 g. acid), b₁₄ 116-17闂?(picrate, m. 138-40闂?. In the experiment, the researchers used many compounds, for example, 4-Methylpicolinonitrile (cas: 1620-76-4Synthetic Route of C7H6N2).

4-Methylpicolinonitrile (cas: 1620-76-4) belongs to pyridine derivatives. Pyridine is diamagnetic and has a diamagnetic susceptibility of 闂?8.7 闂?10闂? cm3闁荤姾娅ｅΛ纭俵闂?.The molecular electric dipole moment is 2.2 debyes. The standard enthalpy of formation is 100.2 kJ闁荤姾娅ｅΛ纭俵闂? in the liquid phase and 140.4 kJ闁荤姾娅ｅΛ纭俵闂? in the gas phase. Pyridine derivatives are also useful as small-molecule 婵?helix mimetics that inhibit protein-protein interactions, as well as functionally selective GABA ligands.Synthetic Route of C7H6N2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Aluminum-catalyzed selective hydroboration of carbonyls and dehydrocoupling of alcohols, phenols, amines, thiol, selenol, silanols with HBpin was written by Sarkar, Nabin;Sahoo, Rajata Kumar;Patro, A. Ganesh;Nembenna, Sharanappa. And the article was included in Polyhedron in 2022.Recommanded Product: Phenyl(pyridin-2-yl)methanone This article mentions the following:

A popular N,N’-chelated NacNac analog, i.e., conjugated bis-guanidinate (CBG) stabilized aluminum dihydride LAlH₂ [1; L = ArNC(ArNH):NC:(NHAr)NAr, where Ar = 2,6-Et₂-C₆H₃], demonstrates excellent catalytic hydroboration of a wide array of carbonyls with pinacolborane (HBpin) under neat conditions with good tolerance of reducible functional groups such as alkyl, alkene, halide, nitrile, nitro, ester, amide, and heteroaryl. In addition, we investigated complex 1 catalyzed cross-dehydrocoupling (CDC) of alcs., phenols, amines, thiol, selenol, and silanols with HBpin under mild reaction conditions. Furthermore, several control experiments have been performed to understand the mechanisms in hydroboration and CDC reactions. All corresponding catalytic intermediates have been identified and characterized by ¹H and ¹³C{¹H} NMR spectroscopic methods. In contrast to several reports on metal-catalyzed hydroboration of carbonyls, this is the second report for the mol. aluminum catalyzed CDC of organic substrates with HBpin. In the experiment, the researchers used many compounds, for example, Phenyl(pyridin-2-yl)methanone (cas: 91-02-1Recommanded Product: Phenyl(pyridin-2-yl)methanone).

Phenyl(pyridin-2-yl)methanone (cas: 91-02-1) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the 闂?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 闂?bonds. 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: Phenyl(pyridin-2-yl)methanone

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Recovery of Syringic Acid from Industrial Food Waste with Aqueous Solutions of Ionic Liquids was written by de Faria, Emanuelle L. P.;Ferreira, Ana M.;Claudio, Ana Filipa M.;Coutinho, Joao A. P.;Silvestre, Armando J. D.;Freire, Mara G.. And the article was included in ACS Sustainable Chemistry & Engineering in 2019.Product Details of 125652-55-3 This article mentions the following:

Phenolic acids present in industrial food waste display a broad range of biol. activities and related health benefits, among which their strong antioxidant and free-radical scavenger activities are the most investigated. However, food waste is still scarcely considered as an alternative source for these compounds, and volatile organic solvents for their extraction are still the preferred choice. In this work, aqueous solutions of ionic liquids (ILs) with hydrotropic or surfactant character were investigated to improve the solubility and effectively extract syringic acid from Rocha pear peels, a relevant waste of the food industry. The solubility of syringic acid in aqueous solutions of a wide variety of ILs at different concentrations at 30闂佺娅ｉ悡?was first ascertained. The results obtained show that ILs that behave as cationic hydrotropes are the best option to enhance the solubility of syringic acid in aqueous media, with increases in solubility of up to 84-fold when compared with water. After identifying the most promising IL aqueous solutions, a response surface methodol. was used to optimize operational extraction conditions (extraction time, solid-liquid (biomass-solvent) ratio, and temperature), leading to a maximum extraction yield of syringic acid of 1.05 wt % from pear peels. Both the solvent and biomass reuse were addnl. investigated, allowing to overcome the biomass-solvent ratio constraints and mass-transfer effects and leading to extraction yields of 2.04 and 2.22 wt %. Although other methods for the recovery of syringic acid can be applied, taking advantage of the hydrotropy phenomenon and the solubility of syringic acid dependency with the IL concentration, water was used as an antisolvent, allowing to obtain 77% of the extracted phenolic acid. A continuous countercurrent process conceptualized for large-scale applications and that further allows the solvent recycling after the recovery of syringic acid is finally proposed. In the experiment, the researchers used many compounds, for example, 1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3Product Details of 125652-55-3).

1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3) belongs to pyridine derivatives. In contrast to benzene, Pyridine’s electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. 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.Product Details of 125652-55-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Design, synthesis and anti-HBV activity evaluation of new substituted imidazo[4,5-b]pyridines was written by Gerasi, Maria;Frakolaki, Efseveia;Papadakis, Georgios;Chalari, Anna;Lougiakis, Nikolaos;Marakos, Panagiotis;Pouli, Nicole;Vassilaki, Niki. And the article was included in Bioorganic Chemistry in 2020.Synthetic Route of C5H3Cl2N3O2 This article mentions the following:

The design and synthesis of a number of new imidazo[4,5-b]pyridines is described. The heterocyclic scaffold possesses 6-chloro- or 5,6-dichloro-substitution and bears various 2-alkylamino-Me or Et groups. The corresponding N¹ and N³-tosylates are also presented. The anti-HBV activity of the compounds was evaluated in HBV infectious system at the level of HBV rcDNA secretion and CC₅₀, EC₅₀ and selectivity index values were determined The tosylates showed low antiviral potency and relatively high cytotoxicity, on the contrary, a number of 2,5 and/or-6-substituted imidazopyridines, mainly those belonging to the 6-chloroimidazo[4,5-b]pyridine series, were endowed with a very interesting profile and were further investigated. The most promising among them, along with the reduction of the secreted HBV rcDNA, also caused a reduction in HBV cccDNA and pgRNA levels, with a concomitant accumulation of the intracellular encapsidated rcDNA. Surprisingly, the most active 6-chloro-2-[2-(diethylamino)ethyl]imidazo[4,5-b]pyridine was highly competitive to interferon. In the experiment, the researchers used many compounds, for example, 5,6-Dichloro-3-nitropyridin-2-amine (cas: 203794-33-6Synthetic Route of C5H3Cl2N3O2).

5,6-Dichloro-3-nitropyridin-2-amine (cas: 203794-33-6) belongs to pyridine derivatives. Pyridines are an important class of heterocycles and occur in polysubstituted forms in many naturally occurring biologically active compounds, drug molecules and chiral ligands. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Synthetic Route of C5H3Cl2N3O2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

PH-Controlled Construction of Cu(I) Coordination Polymers: In Situ Transformation of Ligand, Network Topologies, and Luminescence and UV-vis-NIR Absorption Properties was written by Fang, Zhen-Lan;He, Jian-Gang;Zhang, Qi-Sheng;Zhang, Qi-Kai;Wu, Xiao-Yuan;Yu, Rong-Min;Lu, Can-Zhong. And the article was included in Inorganic Chemistry in 2011.Electric Literature of C12H8N4O This article mentions the following:

Two coordination polymers, [Cu^I₃(L1)I₃]_n (1, L1 = 2,5-bis(4-pyridyl)-1,3,4-oxadiazole) and [Cu^I₃(L2)I₂]_n (2, L2 = 2,5-bis(4-pyridyl)-1,2,4-triazolate), are controllably formed by using aqueous ammonia to regulate the pH value of the reaction involving CuI and L1. L2 of 2 is in situ generated from the ring transform of L1 when increase the pH value of the reaction. 1 Exhibits a 2-dimensional layer, while 2 shows 3-dimensional MOFs with a novel 3-nodal 4,4,5-connected net topol. of an unprecedented Point (Schlafli) symbol: (4闁?²闁?²闁?)(5⁴闁?²)(4³闁?闁?⁶). Although both 1 and 2 are built of CuI and similar ligands, different arrangements of CuI chains and ligands endow them with different phys. properties. 1 Displays a strong pure red luminescence emission, while 2 is non-luminescent and shows a broad absorption band covering the whole UV-visible-NIR spectrum range. The emissive excited states of 1 and the charge transitions of the optical absorption for 2 are solved by DFT calculations In the experiment, the researchers used many compounds, for example, 2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7Electric Literature of C12H8N4O).

2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ闁荤姾娅ｅΛ纭俵闂? in pyridine vs. 150 kJ闁荤姾娅ｅΛ纭俵闂? in benzene). 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. Electric Literature of C12H8N4O

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Novel triazines as potent and selective phosphodiesterase 10A inhibitors was written by Malamas, Michael S.;Stange, Hans;Schindler, Rudolf;Lankau, Hans-Joachim;Grunwald, Christian;Langen, Barbara;Egerland, Ute;Hage, Thorsten;Ni, Yike;Erdei, James;Fan, Kristi Yi;Parris, Kevin;Marquis, Karen L.;Grauer, Steve;Brennan, Julie;Navarra, Rachel;Graf, Radka;Harrison, Boyd L.;Robichaud, Albert;Kronbach, Thomas;Pangalos, Menelas N.;Brandon, Nicholas J.;Hoefgen, Norbert. And the article was included in Bioorganic & Medicinal Chemistry Letters in 2012.Quality Control of 2-Chloro-4-methoxy-3-nitropyridine This article mentions the following:

The identification of highly potent and orally active triazines for the inhibition of PDE10A is reported. The new analogs exhibit low-nanomolar potency for PDE10A, demonstrate high selectivity against all other members of the PDE family, and show desired drug-like properties. Employing structure-based drug design approaches, the authors investigated the selectivity of PDE10A inhibitors against other known PDE isoforms, by methodically exploring the various sub-regions of the PDE10A ligand binding pocket. A systematic assessment of the ADME and pharmacokinetic properties of the newly synthesized compounds has led to the design of drug-like candidates with good brain permeability and desirable drug kinetics (t_1/2, bioavailability, clearance). Compound I was highly potent for PDE10A (IC₅₀ = 1.4 nM), demonstrated high selectivity (>200闂? for the other PDEs, and was efficacious in animal models of psychoses; reversal of MK-801 induced hyperactivity (MED = 0.1 mg/kg) and conditioned avoidance responding (CAR; ID₅₀ = 0.2 mg/kg). In the experiment, the researchers used many compounds, for example, 2-Chloro-4-methoxy-3-nitropyridine (cas: 6980-09-2Quality Control of 2-Chloro-4-methoxy-3-nitropyridine).

2-Chloro-4-methoxy-3-nitropyridine (cas: 6980-09-2) belongs to pyridine derivatives. Pyridines are an important class of heterocycles and occur in polysubstituted forms in many naturally occurring biologically active compounds, drug molecules and chiral ligands. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Quality Control of 2-Chloro-4-methoxy-3-nitropyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Low Catalyst Loadings in Olefin Metathesis: Synthesis of Nitrogen Heterocycles by Ring-Closing Metathesis was written by Kuhn, Kevin M.;Champagne, Timothy M.;Hong, Soon Hyeok;Wei, Wen-Hao;Nickel, Andrew;Lee, Choon Woo;Virgil, Scott C.;Grubbs, Robert H.;Pederson, Richard L.. And the article was included in Organic Letters in 2010.Synthetic Route of C10H17NO2 This article mentions the following:

Ruthenium carbene complexes are compared for their effectiveness as catalysts for the ring-closing metathesis reactions of Boc-protected amines to give Boc-pyrrolidines, Boc-tetrahydropyridines, and Boc-tetrahydroazepines with disubstituted, trisubstituted, and tetrasubstituted olefin moieties. In some cases, ring-closing metathesis reactions are performed with catalyst loadings as low as 0.05 mol.% to give >90% yields of nitrogen heterocycles; tetrasubstituted alkene products require 0.1-0.5 mol.% catalyst loadings to obtain good yields of product. Ring-closing metathesis reactions of bisallylic carbamates to give Boc-pyrrolines could be performed neat, while the corresponding reactions of allylic homoallylic carbamates to give Boc-tetrahydropyridines could be performed at substrate concentrations of 1.0 M and the corresponding reactions of bishomoallylic carbamates to give Boc-tetrahydroazepines work best at substrate concentrations of 0.05-0.2 M. Me tert-Bu ether is used as a solvent in some of the ring-closing metathesis reactions instead of toluene. In the experiment, the researchers used many compounds, for example, tert-Butyl 5,6-dihydropyridine-1(2H)-carboxylate (cas: 85838-94-4Synthetic Route of C10H17NO2).

tert-Butyl 5,6-dihydropyridine-1(2H)-carboxylate (cas: 85838-94-4) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ闁荤姾娅ｅΛ纭俵闂? in pyridine vs. 150 kJ闁荤姾娅ｅΛ纭俵闂? in benzene). 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.Synthetic Route of C10H17NO2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Reactions of N-aminopyridinium derivatives. XII. Nucleophilic reactions of N-aminopyridinium derivatives was written by Ohsawa, Akio;Hirobe, Masaaki;Okamoto, Toshihiko. And the article was included in Yakugaku Zasshi in 1972.Recommanded Product: 1620-76-4 This article mentions the following:

Derivatives of N-aminopyridine were synthesized and these derivatives underwent reaction with nucleophilic reagents. Progress of this reaction depended on the activity of the reagents as a nucleophilic species, substituent effect of the substrate, and reaction conditions. Electron-withdrawing nature of the substituent on the amino group determines the activity of the substrate while that of the substituent on ring C determines the orientation of the reaction, the greater the electron-withdrawing nature of ring C the greater the orientation towards the 2-position. The reaction results in addition and (or) substitution reaction and the reaction can be explained without inconsistency by assuming the progress of this reaction in 2 steps of addition and liberation even when only a substitution product is obtained. Depending on whether the addition step is reversible or irreversible, each step will be controlled either by thermokinetics or by chem. kinetics, and orientation towards the 4- or 2-position will be determined by which of these forces would be stronger. In the experiment, the researchers used many compounds, for example, 4-Methylpicolinonitrile (cas: 1620-76-4Recommanded Product: 1620-76-4).

4-Methylpicolinonitrile (cas: 1620-76-4) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ闁荤姾娅ｅΛ纭俵闂? in pyridine vs. 150 kJ闁荤姾娅ｅΛ纭俵闂? in benzene). 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. Recommanded Product: 1620-76-4

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Heck-Type Coupling of Fused Bicyclic Vinylcyclopropanes: Synthesis of 1,2-Dihydropyridines, 2,3-Dihydro-1H-azepines, 1,4-Cyclohexadienes and 2H-Pyrans was written by Wurzer, Nikolai;Klimczak, Urszula;Babl, Tobias;Fischer, Sebastian;Angnes, Ricardo A.;Kreutzer, Dominik;Pattanaik, Aryaman;Rehbein, Julia;Reiser, Oliver. And the article was included in ACS Catalysis in 2021.Recommanded Product: tert-Butyl 5,6-dihydropyridine-1(2H)-carboxylate This article mentions the following:

Herein, a versatile approach for the endocyclic ring opening of bicyclic vinylcyclopropanes triggered by Heck arylations was reported. The key step for this transformation was a 闁?C-elimination allowing the ring expansion of cyclopropanated pyrroles, piperidines, furans, as well as cyclopentadienes to grant access to the corresponding 1,2-dihydropyridines such as I [R = 1-cyclohexenyl, Ph, 1-naphthyl, etc.], 2H-pyrans II [R¹ = Ph, 4-MeOC₆H₄, 4-MeC₆H₄, etc.], 2,3-dihydro-1H-azepines III [R² = 4-ClC₆H₄, Ph, etc.], and 1,4-cyclohexadienes IV [R³ = 4-i-PrC₆H₄, 2-naphthyl, etc.], resp. Addnl., gem-disubstituted cyclopropanated furans showed unexpected behavior by giving diastereoselectively asym. substituted dienes. Mechanistic studies and theor. calculations point toward a facile 闁?C-elimination with a concomitant shift of Pd along the cyclopropane moiety, which could be successfully compete with the usual termination step of a Heck reaction via a syn-闁?hydride elimination. In the experiment, the researchers used many compounds, for example, tert-Butyl 5,6-dihydropyridine-1(2H)-carboxylate (cas: 85838-94-4Recommanded Product: tert-Butyl 5,6-dihydropyridine-1(2H)-carboxylate).

tert-Butyl 5,6-dihydropyridine-1(2H)-carboxylate (cas: 85838-94-4) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Pyridine derivatives are also useful as small-molecule 婵?helix mimetics that inhibit protein-protein interactions, as well as functionally selective GABA ligands.Recommanded Product: tert-Butyl 5,6-dihydropyridine-1(2H)-carboxylate

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Correlation between lipophilicity of newly synthesized ionic liquids and selected Fusarium genus growth rate was written by Vranes, Milan;Tot, Aleksandar;Cosic, Jasenka;Papovic, Snezana;Panic, Jovana;Gadzuric, Slobodan;Jankovic, Nenad;Vrandecic, Karolina. And the article was included in RSC Advances in 2019.Synthetic Route of C10H16BrN This article mentions the following:

The purpose of the present study was to examine the effectiveness of 23 different synthesized ionic liquids (ILs) on Fusarium culmorum and Fusarium oxysporum growth rate. The strategy of IL synthesis was a structural modification of ionic liquids through changing the polarity of imidazolium and pycolinium cations and replacing halide anions with well known antifungal anions (cinnamate, caffeate and mandelate). The findings clearly suggest that the type of alkyl chain on the cation is the most determining factor for IL toxicity. In order to examine how IL structure affects their toxicity towards Fusarium genus, lipophilic descriptor A log P is calculated from d. functional theory and correlated with Fusarium growth rate. All these results demonstrate the high level of the interdependency of lipophilicity and toxicity for investigated ILs towards the Fusarium genus. The data collected in this research suggest that the inhibitory influence of ILs is more pronounced in the case of F. oxysporum. In the experiment, the researchers used many compounds, for example, 1-Butyl-4-methylpyridin-1-ium bromide (cas: 65350-59-6Synthetic Route of C10H16BrN).

1-Butyl-4-methylpyridin-1-ium bromide (cas: 65350-59-6) 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. 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.Synthetic Route of C10H16BrN

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem