Month: December 2022

Kiselyov, Alexander S. published the artcileSynthesis of 2-substituted pyridines by the reaction of N-fluoropyridinium fluoride with trimethylsilyl derivatives, Product Details of C6H5F4NO3S, the publication is Journal of Organic Chemistry (1993), 58(16), 4476-8, database is CAplus.

A 1-pot preparation of 2-substituted pyridines in the reaction of N-fluoropyridinium fluoride generated in situ with C-, O- and N-(trimethylsilyl) compounds in the presence of a catalytic amount of Bu₄NF is described. Treatment of 1-fluoropyridinium fluoride with Et (trimethylsilyl)acetate gave Et 2-pyridineacetate (I) in 55% yield.

Journal of Organic Chemistry published new progress about 107263-95-6. 107263-95-6 belongs to pyridine-derivatives, auxiliary class Fluorination reagent, name is 1-Fluoropyridiniumtriflate, and the molecular formula is C6H5F4NO3S, Product Details of C6H5F4NO3S.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Kiselyov, Alexander S. published the artcileA highly regioselective reaction of N-fluoropyridinium salts with stabilized sulfur, oxygen, and nitrogen nucleophiles: a convenient route to 2-substituted pyridines, HPLC of Formula: 107263-95-6, the publication is Journal of Heterocyclic Chemistry (1993), 30(5), 1361-4, database is CAplus.

2-Substituted pyridines I (R = phenoxy, phenylthio, imidazolyl, triazolyl, etc.) are efficiently obtained by the reactions of N-fluoropyridinium salts II (X = tetrafluoroborate, triflate) with anions derived from benzenethiols, phenols, azoles, cyanamide, and with azide anion. The results are consistent with a nucleophile addition at the position 2 of the N-fluoropyridinium cation as the major reaction pathway. The Reissert-Henze reaction of N-methoxypyridinium perchlorate to give I was unsuccessful.

Journal of Heterocyclic Chemistry published new progress about 107263-95-6. 107263-95-6 belongs to pyridine-derivatives, auxiliary class Fluorination reagent, name is 1-Fluoropyridiniumtriflate, and the molecular formula is C6H5F4NO3S, HPLC of Formula: 107263-95-6.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Arning, Juergen published the artcileQualitative and quantitative structure activity relationships for the inhibitory effects of cationic head groups, functionalized side chains and anions of ionic liquids on acetylcholinesterase, Quality Control of 17281-59-3, the publication is Green Chemistry (2008), 10(1), 47-58, database is CAplus.

To contribute to a deeper insight into the hazard potential of ionic liquids to humans and the environment, an acetylcholinesterase (AchE) inhibition screening assay was used to identify toxicophore substructures and interaction potentials mediating enzyme inhibition. The pos. charged nitrogen atom, a widely delocalized aromatic system, and the lipophilicity of the side chains connected to the cationic head groups can be identified as the key structural elements in binding to the enzymes active site. With respect to this, the dimethylaminopyridinium, the quinolinium and the pyridinium head groups exhibit a very strong inhibitory potential to the enzyme with IC₅₀ values around 10 μM. In contrast, the polar and non-aromatic morpholinium head group is found to be only weakly inhibiting to the enzyme activity, with IC₅₀ values > 500 μM. The introduction of polar hydroxy, ether or nitrile functions into the alkyl side chain is shown to be a potent structural alteration to shift the corresponding ionic liquids to a lower inhibitory potential. Supporting this fact, for a series of imidazolium cations, a QSAR correlation was set up by the linear regression of the log IC₅₀ vs. the logarithm of the HPLC-derived lipophilicity parameter k₀. Addnl., a broad set of anion species (inorganic, organic and complex borate anions), commonly used as ionic liquid counterions, was tested and the vast majority exhibited no effect on AchE. Only the fluoride and fluoride containing anion species which readily undergo hydrolytic cleavage can be identified to act as AchE inhibitors.

Green Chemistry published new progress about 17281-59-3. 17281-59-3 belongs to pyridine-derivatives, auxiliary class Pyridine,Nitrile,Salt, name is 1-(Cyanomethyl)pyridin-1-ium chloride, and the molecular formula is C7H7ClN2, Quality Control of 17281-59-3.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Kader, Thomas published the artcileAzaindolo[3,2,1-jk]carbazoles: New Building Blocks for Functional Organic Materials, Application of 2-Bromopyridin-3-amine, the publication is Chemistry – A European Journal (2019), 25(17), 4412-4425, database is CAplus and MEDLINE.

The preparation and characterization of 12 azaindolo[3,2,1-jk]carbazoles, e.g., I was presented. Ring-closing C-H activation allowed for the convenient preparation of six singly and six doubly nitrogen-substituted indolo[3,2,1-jk]carbazole derivatives in which ten of the materials had not been described in the literature before. The detailed photophys. and electrochem. characterization of the developed materials revealed a significant impact of the incorporation of pyridine-like nitrogen into the fully planar indolo[3,2,1-jk]carbazole backbone. Furthermore, the nitrogen position decisively impacted intermol. hydrogen bonding and thus the solid-state alignment. Ultimately, the versatility of the azaindolo[3,2,1-jk]carbazoles scaffold makes this class of materials an attractive new building block for the design of functional organic materials.

Chemistry – A European Journal published new progress about 39856-58-1. 39856-58-1 belongs to pyridine-derivatives, auxiliary class Pyridine,Bromide,Amine, name is 2-Bromopyridin-3-amine, and the molecular formula is C5H5BrN2, Application of 2-Bromopyridin-3-amine.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Pischedda, Sara published the artcileSynthesis and characterization of new Pd(II) and Pt(II) complexes with 3-substituted 1-(2-pyridyl)imidazo[1,5-a]pyridine ligands, Quality Control of 91-02-1, the publication is Dalton Transactions (2021), 50(14), 4859-4873, database is CAplus and MEDLINE.

Several palladium(II) and platinum(II) complexes (1–20) of general formula [M(Lⁿ)(X)(Y)] [M = Pd, X = Y = Cl (1–Cl–4–Cl), X = Y = OAc (1–OAc–4–OAc); M = Pt: X = Y = Cl (5–8); M = Pd, X = Cl, Y = CH₃ (9–12); M = Pt, X = Cl, Y = CH₃ (13–16) or X = Y = CH₃ (17–20); n = 1-4] have been synthesized by reaction of different Pd(II) and Pt(II) derivatives with various 3-substituted 1-(2-pyridyl)-imidazo[1,5-a]pyridines; i.e. Lⁿ = 1-(2-pyridyl)-3-arylimidazo[1,5-a]pyridine (aryl = Ph, L¹; 2-o-Tolyl, L²; Mesityl, L³) and 1-(2-pyridyl)-3-benzylimidazo[1,5-a]pyridine (L⁴). Detailed spectroscopic investigation (including IR, mono- and bi-dimensional ¹H NMR) and elemental anal. has been performed for all these species, allowing their complete characterization. Lⁿ act as N,N-bidentate ligands and coordinate the metal centers in a chelate fashion through the pyridyl (N_py) and the pyridine-like nitrogen atom of the imidazo[1,5-a]pyridine group (N_im). The x-ray structural anal. performed on two of Pd(II) and three Pt(II) complexes, namely [Pd(L²)(CH₃)Cl] (10), [Pd(L³)(CH₃)Cl] (11) and [Pt(L¹)Cl₂] (5), [Pt(L⁴)Cl₂] (8), [Pt(L²)(CH₃)Cl] (14) confirmed the spectroscopic and anal. data. Finally DFT studies unveiled the structural reasons behind the inertia of the synthesized compounds toward metalation, identified as the higher angle steric strain in comparison with the analogous bipyridine complexes.

Dalton Transactions published new progress about 91-02-1. 91-02-1 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene,Ketone, name is Phenyl(pyridin-2-yl)methanone, and the molecular formula is C12H9NO, Quality Control of 91-02-1.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Deady, Leslie W. published the artcileMechanisms for the acetylation of aminopyridines, Related Products of pyridine-derivatives, the publication is Australian Journal of Chemistry (1978), 31(8), 1725-30, database is CAplus.

Rates of acetylation of aminopyridines and some ring methyl-substituted derivatives, with acetic anhydride in acetone at 36°, are reported. Rate-determining acetylation is directly at the amino nitrogen for all 2- and 3-aminopyridines studied. Reaction through a ring N-acetyl intermediate occurs for 4-aminopyridine but the presence of a 2-Me substituent blocks this pathway.

Australian Journal of Chemistry published new progress about 18437-58-6. 18437-58-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine, name is 4-Amino-2-picoline, and the molecular formula is C6H8N2, Related Products of pyridine-derivatives.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Neumann, Jennifer published the artcileBiodegradability of 27 pyrrolidinium, morpholinium, piperidinium, imidazolium and pyridinium ionic liquid cations under aerobic conditions, Synthetic Route of 17281-59-3, the publication is Green Chemistry (2014), 16(4), 2174-2184, database is CAplus.

The chem. and thermal stability of ionic liquids (ILs) makes them interesting for a large variety of applications in nearly all areas of the chem. industry. However, this stability is often reflected in their recalcitrance towards biodegradation, which comes with the risk of persistence when they are released into the environment. The authors carried out a systematic study of the biodegradability of pyrrolidinium, morpholinium, piperidinium, imidazolium and pyridinium-based IL cations substituted with different alkyl or functionalized side chains and using halide counterions. The authors examined their primary degradability by specific anal. and/or their ultimate biodegradability using BOD tests according to OECD guideline 301F. Biol. transformation products were studied using mass spectrometry. A comparison of the biodegradation potential of these ILs shows that for all five head groups, representatives can be found that are readily or inherently biodegradable, thus permitting the structural design of ILs with a reduced environmental hazard.

Green Chemistry published new progress about 17281-59-3. 17281-59-3 belongs to pyridine-derivatives, auxiliary class Pyridine,Nitrile,Salt, name is 1-(Cyanomethyl)pyridin-1-ium chloride, and the molecular formula is C7H7ClN2, Synthetic Route of 17281-59-3.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Eisenmann, Michael published the artcileStructure-based optimization of aldose reductase inhibitors originating from virtual screening, Recommanded Product: 2-Pyridinylboronic acid, the publication is ChemMedChem (2009), 4(5), 809-819, database is CAplus and MEDLINE.

Virtual screening discovered two prospective hits as potential leads for aldose reductase inhibition. Based on their crystal structures with the enzyme, a systematic optimization has been performed to reveal a first structure-activity relationship. A central thiophen moiety and a terminal nitro group exhibit the best binding properties. Diabetes mellitus is a universal health problem. The World Health Organization (WHO) estimates that 150 million people suffer from diabetes mellitus worldwide in 2005. Long-term complications are a serious problem in the treatment of diabetes, manifesting in macrovascular and microvascular complications. Sorbitol accumulation has been proposed to be an important factor in the development of microvascular complications such as nephropathy, neuropathy, retinopathy or cataract. Catalyzing the NADPH-dependent reduction of glucose to sorbitol, aldose reductase (ALR2) is an important target in the prevention of these complications. The development of novel aldose reductase inhibitors is expected to benefit strongly from a structure-based design approach. A virtual screening based on the ultrahigh-resolution crystal structure of the inhibitor IDD 594 in complex with human ALR2 identified two compounds with IC₅₀ values in the low micro- to submicromolar range. Based on the known interactions between the ligands and their binding pocket, we simplified the lead structures to give the minimal structural requirements and developed synthetic pathways from com. available compounds The newly synthesized compounds were assayed for their inhibition of ALR2, showing inhibitory activities down to the nanomolar range. Crystal structure anal. of the most potent derivative of our series revealed insights into the binding mode of the inhibitors.

ChemMedChem published new progress about 197958-29-5. 197958-29-5 belongs to pyridine-derivatives, auxiliary class Pyridine,Boronic acid and ester, name is 2-Pyridinylboronic acid, and the molecular formula is C5H6BNO2, Recommanded Product: 2-Pyridinylboronic acid.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Petrow, V. published the artcileAnalgesics. II. Aryloxyalkyl oxaalkylamines, Recommanded Product: 4-Amino-2-picoline, the publication is Journal of Pharmacy and Pharmacology (1958), 86-95, database is CAplus and MEDLINE.

cf. C.A. 51, 8723b. Compounds formally related to aryloxypropanolamine in which the aryl and amine residues are joined by combinations derived from glycerol and ethylene glycol are synthesized. Adding 108 g. ο-cresol to 40 g. NaOH in 450 ml. EtOH and 40 ml. H₂O followed by 143 g. (ClCH₂CH₂)₂O and refluxing 5 hrs. formed an oil with fractons b_0.3 36-95° (52.4 g.), 100-20° (111.9 g.), and 160° (26.9 g.). The 2nd fraction yielded 5-ο-tolyloxy-3-oxapentyl chloride (I), b_0.3 92°, and the 3rd fraction yielded 1,5-bis-ο-tolyloxy-3-oxapentane, b_0.3 156°. I was heated with piperidine to form N-(5-ο-tolyloxy-3-oxapentyl)piperidine, b_0.3 130° (picrate, yellow nodules from EtOAc-ligroine, m. 77- 8°). N-(5-ο-Tolyloxy-3-oxapentyl)pyrrolidine, oil, b_0.3 122°; Δ³-piperideine analog, b_0.3 138° (picrate, yellow needles from EtOAc-ligroine, m. 92-4°). 3-Phenoxy-1,2-epoxy- propane and N-(2-hydroxyethyl)piperidine in C₆H₆ were refluxed 20 hrs. to form N-(5-hydroxy-6-phenoxy-3-oxahexyl)-piperidine, b_0.1. 150°; the 6-ο-methoxyphenoxy-3-oxahexyl analog b_0.1 160°. 2-ο-Tolyloxyethanol and 2,3-epoxypropyl chloride with polyphosphoric acid were heated at 100° for 20 hrs. to form 2-hydroxy-6-ο-tolyloxy-4-oxahexyl chloride, b_0.5 136°. 2-ο-Tolyloxyethanol was refluxed with NaOMe in MeOH for several min., the residual product was suspended in dry C₆H₆, 1-chloro-2,3-epoxypropane added, and the mixture refluxed 8 hrs. to yield from the main distillation fraction 1,2-epoxy-6-ο-tolyloxy-4-oxahexane (II) (oil, b_0.05 100°) and from the top fraction a viscous oil, b_0.07 210°. Treatment of the foregoing chlorohydrin with an equivalent of KOH in MeOH at 0° followed by dilution and extraction with CHCl₃ yielded II. II in C₆H₆ with Δ³-piperideine formed N-(2-hydroxy-6-ο-tolyloxy-4-oxahexyl)-Δ³-piperideine, b_0.3 162° [HCl salt, hygroscopic, m. 50-60°; picrate, m. 81-3° (EtOAc-Et₂O)]. 3-ο-Tolyloxy-1,2-epoxypropane and allyl alc. treated carefully with H₂SO₄ and heated at 100° for 2 hrs. yielded from the residual fraction b_0.25 120° 6-hydroxy-7-ο-tolyloxy-4-oxa-1-heptene (III), b_1.2 130-2°; the fraction b_0.25-1 124-44° contained a high proportion of 3-ο-tolyloxypropane-1,2-diol. 2-Hydroxy-3-ο-tolyloxypropyl chloride (100 g.) and 232 g. allyl alc. with 33.6 g. powd. KOH added in portions then heated at 100° for 8 hrs., diluted, and extracted with CHCl₃ yielded 97.8 g. III, b_0.1 113°. Adding 63 g. III to a cold solution of 39.15 g. perbenzoic acid in 995 ml. C₆H₆, keeping at 0° for 2 days and then room temperature for 2 days, and refractionating the fraction (37.7 g.), b_0.3 118-50°, yielded 1,2-epoxy-6-hydroxy-7-ο-tolyloxy-4-oxaheptane, b_0.4 144°, which condensed with Et₂NH in C₆H₆ to form N-(2,6-dihydroxy-7-ο-tolyloxy-4-oxaheptyl)diethylamine, b_0.3 174° (piperidine analog, b_0.4 194°). 6-Hydroxy-7-phenoxy-4-oxa-1-heptene b_0.05 110°. 1,2-Epoxy-6-hydroxy-7-phenoxy-4-oxaheptane b_0.4 140°. N-(2,6-Dihydroxy-4-oxahexyl)-p-anisidine, m. 65-7° (EtOAc-ligroine), refluxed 5 hrs. in MeOH with MeI and Na₂CO₃ formed N-methyl-N-(2,6-dihydroxy-4-oxahexyl)-p-anisidine, b_0.1 180°; the N-Et analog, b_0.1 185°. N-(2,6-Dihydroxy-4-oxahexyl)-p-phenetidine (by alk. condensation in MeOH), light yellow prisms, m. 70-2° (EtOAc-ligroine) [picrate, m. 127-8° (EtOH)]; N-Et derivative, _0.3 180°. N (2,6-Dihydroxy-4-oxahexyl)-p-propoxyaniline (61% yield) b_0.1 192-8°, light yellow needles, m. 71-3° (EtOAc-ligroine); p-butoxyaniline analog, b_0.4 195-200°, yellow needles, m. 69-71° (EtOAc-ligroine); ο-phenetidine analog, b_0.4 182-6°, pale yellow needles, m. 57-8° (EtOAc-ligroine); morpholine analog, b_0.5 144°; Δ³-piperideine analog, b_0.3, 140°; pyrrolidine analog, b_0.1 118°. N-(2,9-Dihydroxy-4,7-dioxanonyl)-p-phenetidine b_0.5 220°; picrate, bright yellow needles, m. 120-1° (EtOAc). N-(2,6-Dihydroxy-4-oxaheptyl)-p-phenetidine on fractionation (b_0.04-0.05 200-5°) gave a white solid (A), m. 102-4° (EtOAc-ligroine), soluble in hot H₂O; picrate, yellow fluffy needles, m. 130-2° (EtOAc). The concentrated mother liquors from A yielded a main fraction B, b_0.8 210°, m. 54-6° (Et₂O-ligroine), more soluble in cold H₂O than A. Tentative structures were for A, p-EtC₆H₄NHCH₂CH(OH)CH₂OCH₂CH(OH)Me, for B, p-EtC₆H₄NHCH₂CH(OH)CH₂OCHMeCH₂OH. The p-anisidine analog fractionated by b_0.5 200-20° yielded 2 isomers; the less soluble crystallized from H₂O [picrate, m. 134-6° (EtOAc-ligroine)]; the more soluble m. 64-6° (Et₂O-ligroine) [picrate, m. 12 6° (EtOAc-ligroine)]. Tentative structures were analogous to those of A and B. N-p-Ethoxyphenylmorpholine b_0.5 120°, m. 75-6° (EtOH-H₂O); HCl salt, m. 170-1° (EtOH-Et₂O). 3-(3,4,5-Trimethoxyphenyl)aminopropane-1,2-diol b_0.2 210°; HCl salt, white needles with blue-green tinge, m. 148-50° (EtOH-Et₂O). 4-ο-Tolyloxybut-2-yn-1-yl chloride b_0.3 110°. 1-Diethylamino-4-phenoxybut-2-yne, from 4-phenoxybut-2-yn-1-yl chloride and Et₂NH as the base, b_0.2 110-15°; HCl salt, m. 138-9° (EtOH-Et₂O). 1-Diethylamino-4-ο-tolyloxybut-2-yne b_0.6 126-8°; HCl salt, m. 116-17° (EtOH-Et₂O). 1-Δ³-Piperideino-4-ο-tolyloxybut-2-yne b_0.5 130°; HCl salt, m. 126-7° (iso-PrOH-Et₂O).

Journal of Pharmacy and Pharmacology published new progress about 18437-58-6. 18437-58-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine, name is 4-Amino-2-picoline, and the molecular formula is C6H8N2, Recommanded Product: 4-Amino-2-picoline.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Stambuli, James P. published the artcileScreening of Homogeneous Catalysts by Fluorescence Resonance Energy Transfer. Identification of Catalysts for Room-Temperature Heck Reactions, Computed Properties of 338800-13-8, the publication is Journal of the American Chemical Society (2001), 123(11), 2677-2678, database is CAplus and MEDLINE.

The authors report a method to screen for transition metal-catalyzed reactions based on Fluorescence Resonance Energy Transfer (FRET) and the use of this assay to identify catalysts for room-temperature Heck reactions of aryl bromides.

Journal of the American Chemical Society published new progress about 338800-13-8. 338800-13-8 belongs to pyridine-derivatives, auxiliary class Bis-phosphine Ligands, name is 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, and the molecular formula is C22H23ClN4, Computed Properties of 338800-13-8.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem