Tag: M.W=200-250

Novak, Michael published the artcileNitrenium ions from food-derived heterocyclic arylamine mutagens, Name: 5-Nitro-2-phenylpyridine, the publication is Journal of the American Chemical Society (1998), 120(7), 1643-1644, database is CAplus.

The pivalic acid esters I (X = N, Y = CH, R = H, Me; X = CH, Y = N, R = H), models for the ultimate mutagenic and carcinogenic metabolites of heterocyclic arylamines, undergo spontaneous uncatalyzed hydrolysis under physiol. pH conditions, but become unreactive under acidic conditions in which the pyridyl N atom is protonated. Kinetic comparisons with the biphenyl ester I (X = Y = CH, R = H) show that the limiting hydrolysis rate constant, k₀, is reduced by substitution of an N atom for a C atom by ∼10⁴ for an ortho substitution and ∼30 for a meta substitution. The hydrolysis rates of these esters are insensitive to added N₃^–, but this nucleophile has considerable effect on reaction products. These results are consistent with a mechanism in which rate-limiting N-O bond heterolysis yields a nitrenium ion that is competitively trapped by solvent and N₃^–. The selectivity ratios, k_az/k_s, for the corresponding ions II (X ≠ Y) are ∼10-300-fold smaller than k_az/k_s for the 4-biphenylylnitrenium ion, II (X = Y = CH).

Journal of the American Chemical Society published new progress about 89076-64-2. 89076-64-2 belongs to pyridine-derivatives, auxiliary class Pyridine,Nitro Compound,Benzene, name is 5-Nitro-2-phenylpyridine, and the molecular formula is C11H8N2O2, Name: 5-Nitro-2-phenylpyridine.

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

Saielli, Giacomo published the artcileOne-bond ¹J(¹⁵N-¹⁹F) spin-spin coupling constants of cationic fluorinating reagents: Insights from DFT calculations, Product Details of C6H5F4NO3S, the publication is Magnetic Resonance in Chemistry (2020), 58(6), 548-558, database is CAplus and MEDLINE.

We have investigated, by means of d. functional theory protocols, the one-bond ¹J(¹⁵N-¹⁹F) spin-spin coupling constants in a series of fluorinating reagents, containing the N-F bond, recently studied exptl. The results of the calculations show a very good linear relationship with the exptl. values, even though only the M06-2X(PCM)/pcJ-2//B3LYP/6-311G(d,p) level affords a very low mean absolute error. The calculations allow to analyze the various MOs contributions to the J coupling and to rationalize the observed pos. sign, corresponding to a neg. sign of the reduced spin-pin coupling constant K(N-F). Moreover, of the four Ramsey contributions, only the diamagnetic spin orbit is negligible, whereas the paramagnetic spin orbit and spin dipole terms decrease the magnitude of the Fermi contact (FC) term by an amount that goes from a min. of 35% up to more than 60% of the FC term itself. Several effects have been investigated, namely, the contribution of the long-range solvent reaction field, relativistic corrections, and conformational and vibrational effects.

Magnetic Resonance in 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

Li, Xing published the artcileNewly-generated Al(OH)₃-supported Pd nanoparticles-catalyzed Stille and Kumada coupling reactions of diazonium salts, (Het)aryl chlorides, Quality Control of 89076-64-2, the publication is Tetrahedron (2016), 72(1), 69-75, database is CAplus.

A ligand-free Pd/Al(OH)₃ nano-catalyst which is prepared by one-pot three-component method using Pd(PPh₃)₄, tetra (ethylene glycol), and aluminum tri-sec-butoxide exhibits excellent catalytic activity in Stille cross-couplings of (Het)aryl chlorides, arenediazonium tetrafluoroborate salts with phenyltributylstannane, resp., and Kumada couplings of (Het)aryl chlorides with various Grignard reagents. More importantly, these two processes show excellent functional group compatibility with moderate to good yields and they are also versatile with respect to not only (Het)aryl chlorides, but also diazonium salts, and heteroaryl Grignard reagents. The nano-catalyst could also be recycled and reused 5 times without loss of activity and decrease of yield.

Tetrahedron published new progress about 89076-64-2. 89076-64-2 belongs to pyridine-derivatives, auxiliary class Pyridine,Nitro Compound,Benzene, name is 5-Nitro-2-phenylpyridine, and the molecular formula is C11H8N2O2, Quality Control of 89076-64-2.

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

Asahara, Haruyasu published the artcileSubstituent Diversity-directed Synthesis of Nitropyridines and Nitroanilines by Three-component Ring Transformation, Quality Control of 89076-64-2, the publication is Procedia Engineering (2017), 1046-1057, database is CAplus.

A novel method for synthesis of various kinds of nitroarenes by using a three-component ring transformation (TCRT) of dinitropyridone with ketones in the presence of ammonium acetate as nitrogen source is developed. This method requires only simple manipulations and mild reaction conditions. Furthermore, the modification of obtained nitropyridine or nitroaniline frameworks can be easily obtained only changing a com. available substrates.

Procedia Engineering published new progress about 89076-64-2. 89076-64-2 belongs to pyridine-derivatives, auxiliary class Pyridine,Nitro Compound,Benzene, name is 5-Nitro-2-phenylpyridine, and the molecular formula is C11H8N2O2, Quality Control of 89076-64-2.

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

El-Assal, Mona Ibrahim published the artcileNano-sponge novel drug delivery system as carrier of anti-hypertensive drug, Computed Properties of 89076-64-2, the publication is International Journal of Pharmacy and Pharmaceutical Sciences (2019), 11(10), 47-63, database is CAplus.

The study was designed to prepare Nano-sponge formulation loaded with nifedipine. Studying parameters which affecting the formulas in addition to pharmacokinetics and toxicity tests. Nine Nano-sponge formulations were prepared by the solvent evaporation technique. Different ratios of polymer ethylcellulose, COpolymers β-cyclodextrin and hydroxypropyl β-cyclodextrin in addition to solubilizing agent polyvinyl alc. were used. Thermal anal., X-ray powder diffraction (XRPD), shape and surface morphol., particle size, %production yield, %porosity, % swelling, and % drug entrapment efficiency of Nano-sponge were examined Release kinetic also studied beside comparison of pharmacokinetic parameters of the optimum choice formula and marketed one in addition to Toxicol. consideration. Particle size in the range of 119.1 nm to 529 nm which were increased due to the increase in the concentration of polymer to the drug. Nano-sponge revealed porous, spherical nature. Increased in the drug/polymer molar ratios (1:1 to 1:3) may increase their % production yield ranged from 62.1% to 92.4%. The drug content of different formulations was in the range of 77.9% to 94.7%, and entrapment efficiency was in the range of 82.72 % to 96.63%. Drug released in controlled sustained pattern and followed Higuchi, s diffusion mechanism. Pharmacokinetic parameters of optimized formula showed significant higher maximum plasma drug concentration, area under plasma concentration-time curve, volume of distribution and mean residence time. Nano-sponge loaded drug proved biol. safety at low concentrations Nano-sponge drug delivery system has showed small Nano size, porous with controlled drug release and significant-high plasma drug concentration that improved solubility, drug bioavailability and proved safety.

International Journal of Pharmacy and Pharmaceutical Sciences published new progress about 89076-64-2. 89076-64-2 belongs to pyridine-derivatives, auxiliary class Pyridine,Nitro Compound,Benzene, name is 5-Nitro-2-phenylpyridine, and the molecular formula is C11H8N2O2, Computed Properties of 89076-64-2.

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

Kiselyov, Alexander S. published the artcileA novel three-component reaction of N-fluoropyridinium salts: a facile approach to imidazo[1,2-a]pyridines, Formula: C6H5F4NO3S, the publication is Tetrahedron Letters (2005), 46(26), 4487-4490, database is CAplus.

The reaction of N-fluoropyridinium triflates I (R¹ = H, 2-Me, 4-Me₂CH, 2-Ph, 3-Cl, etc.) with isonitriles R²NC (R² = Me₂CH, Me₃C, EtO₂CH₂, cyclohexyl, Ph, PhCH₂, etc.) in acetonitrile or propionitrile in the presence of NaBH(OAc)₃ led to the formation of the corresponding imidazo[1,2-a]pyridines II (R³ = Me, Et) in 44-73% yields. The proposed reaction mechanism involves the intermediate formation of a highly reactive carbene species and apparent reduction of the pyridinium intermediate with NaBH(OAc)₃ to yield the targeted heterocycles.

Tetrahedron Letters 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, Formula: C6H5F4NO3S.

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

Kiselyov, Alexander S. published the artcileReaction of N-fluoropyridinium salts with Wittig reagents: a novel and convenient approach to symmetric trans-olefins, Category: pyridine-derivatives, the publication is Tetrahedron Letters (1994), 35(48), 8951-4, database is CAplus.

N-fluoropyridinium salts react with Wittig reagents containing electron-withdrawing groups to give olefins in 47-83% yield. The mechanism of this conversion is believed to involve single-electron transfer from Wittig reagent to N-fluoropyridinium cation.

Tetrahedron Letters 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, Category: pyridine-derivatives.

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

Xin, Minhang published the artcileSynthesis and biological evaluation of novel 7-substituted 3-(4-phenoxyphenyl)thieno[3,2-c]pyridin-4-amines as potent Bruton’s tyrosine kinase (BTK) inhibitors, COA of Formula: C10H18BNO4, the publication is Bioorganic & Medicinal Chemistry (2015), 23(19), 6250-6257, database is CAplus and MEDLINE.

A series of novel 7-substituted 3-(4-phenoxyphenyl)thieno[3,2-c]pyridin-4-amines I [R¹ = piperidin-3-yl, piperidin-4-yl, 1,2,3,6-tetrahydropyridin-4-yl, etc.] as potent BTK inhibitors were designed, synthesized and evaluated. These thieno[3,2-c]pyridin-4-amine derivatives displayed variant inhibitory activities against BTK in vitro. Among these, 7-pyrazol-4-yl substituted 3-(4-phenoxyphenyl)thieno[3,2-c]pyridin-4-amine subseries showed high BTK inhibition and several compounds displayed superior BTK inhibitory activity. Comprehensive SAR was disclosed and compound I [R¹ = 1-morpholinoethanoe-2-yl] showed excellent potency (IC₅₀ = 11.8 nM), outstanding hydrophilicity (A log P = 3.53), and relatively good kinase selectivity, being a promising lead for further evaluation.

Bioorganic & Medicinal Chemistry published new progress about 844501-00-4. 844501-00-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Boronic acid and ester,Amide,Boronic Acids,Boronic acid and ester, name is (1-(tert-Butoxycarbonyl)-1,2,3,6-tetrahydropyridin-4-yl)boronic acid, and the molecular formula is C9H6N2O2, COA of Formula: C10H18BNO4.

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

Ren, Hailong published the artcileCobalt-Catalyzed Regioselective Borylation of Arenes: N-Heterocyclic Silylene as an Electron Donor in the Metal-Mediated Activation of C-H Bonds, Name: 2,3-Dimethyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine, the publication is Chemistry – A European Journal (2017), 23(24), 5663-5667, database is CAplus and MEDLINE.

C-H Borylation of arenes has been a subject of great interest recently because of its atom-economy and the wide applicability of borylated products in value-added synthesis. A new bis(silylene)cobalt(II) complex bearing a bis(N-heterocyclic silylene)-pyridine pincer ligand (SiNSi) has been synthesized and structurally characterized. It enabled the regioselective catalytic C-H borylation of pyridines, furans, and fluorinated arenes. Notably, it exhibited complementary regioselectivity for the borylation of fluorinated arenes compared to previously known catalytic systems, demonstrating that N-heterocyclic silylene donors have enormous potential in metal-catalyzed catalytic applications.

Chemistry – A European Journal published new progress about 741709-65-9. 741709-65-9 belongs to pyridine-derivatives, auxiliary class Pyridine,Boronic acid and ester,Pyridine,Boronate Esters,Boronic Acids,Boronic acid and ester, name is 2,3-Dimethyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine, and the molecular formula is C13H20BNO2, Name: 2,3-Dimethyl-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine.

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

Liu, Xuemei published the artcileEffect of halogenated substituents on the metabolism and estrogenic effects of the equine estrogen, equilenin, Application In Synthesis of 107263-95-6, the publication is Chemical Research in Toxicology (2003), 16(6), 741-749, database is CAplus and MEDLINE.

Estrogen replacement therapy has been correlated with an increased risk for developing breast and endometrial cancers. One potential mechanism of estrogen carcinogenesis involves metabolism of estrogens to 2- and 4-hydroxylated catechols, which are further oxidized to electrophilic/redox active o-quinones that have the potential to both initiate and promote the carcinogenic process. Previously, the authors showed that the equine estrogens, equilin and equilenin, which are major components of the estrogen replacement formulation Premarin (Wyeth-Ayerst), are primarily metabolized to the catechol, 4-hydroxyequilenin. This catechol was found to autoxidize to an o-quinone causing oxidation and alkylation of DNA in vitro and in vivo. To block catechol formation from equilenin, 4-halogenated equilenin derivatives were synthesized. These derivatives were tested for their ability to bind to the estrogen receptor, induce estrogen sensitive genes, and their potential to form catechol metabolites. The authors found that the 4-fluoro derivatives were more estrogenic than the 4-chloro and 4-bromo derivatives as demonstrated by a higher binding affinity for estrogen receptors α and β, an enhanced induction of alk. phosphatase activity in Ishikawa cells, pS2 expression in S30 cells, and PR expression in Ishikawa cells. Incubation of these compounds with tyrosinase in the presence of GSH showed that the halogenated equilenin compounds formed less catechol GSH conjugates than the parent compounds, equilenin and 17β-hydroxyequilenin. In addition, these halogenated compounds showed less cytotoxicity in the presence of tyrosinase than the parent compounds in S30 cells. Also, as stated above, the 4-fluoro derivatives showed similar estrogenic effects as compared with parent compounds; however, they were less toxic in S30 cells as compared to equilenin and 17β-equilenin. Because 17β-hydroxy-4-halogenated equilenin derivatives showed higher estrogenic effects than the halogenated equilenin derivatives in vitro, the authors studied the relative ability of the 17β-hydroxy-4-halogenated equilenin derivatives to induce estrogenic effects in the ovariectomized rat model. The 4-fluoro derivative showed higher activity than 4-chloro and 4-bromo derivatives as demonstrated by inducing higher vaginal cellular differentiation, uterine growth, and mammary gland branching. However, 17β-hydroxy-4-fluoroequilenin showed a lower estrogenic activity than 17β-hydroxyequilenin and estradiol, which could be due to alternative pharmacokinetic properties for these compounds These data suggest that the 4-fluoroequilenin derivatives have promise as alternatives to traditional estrogen replacement therapy due to their similar estrogenic properties with less overall toxicity.

Chemical Research in Toxicology 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, Application In Synthesis of 107263-95-6.

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