Category: pyridine-derivatives

Doyle, Laurence R. published the artcileA Convenient Synthetic Protocol to 1,2-Bis(dialkylphosphino)ethanes, COA of Formula: C23H43NP2, the publication is Advanced Synthesis & Catalysis (2014), 356(2-3), 603-608, database is CAplus and MEDLINE.

1,2-Bis(dialkylphosphino)ethanes are readily prepared from the parent phosphine oxides, via a novel NaAlH₄/NaH reduction protocol of intermediate chlorophosphonium chlorides. This approach is amenable to multi-gram syntheses, uses readily available and inexpensive reagents, and benefits from a facile nonaqueous work-up in the final reductive step.

Advanced Synthesis & Catalysis 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 C23H43NP2, COA of Formula: C23H43NP2.

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

Murayama, Hiroaki published the artcileIridium-Catalyzed Enantioselective Transfer Hydrogenation of Ketones Controlled by Alcohol Hydrogen-Bonding and sp³-C-H Noncovalent Interactions, Application of Phenyl(pyridin-2-yl)methanone, the publication is Advanced Synthesis & Catalysis (2020), 362(21), 4655-4661, database is CAplus.

Iridium-catalyzed enantioselective transfer hydrogenation of ketones with formic acid was developed using a prolinol-phosphine chiral ligand. Cooperative action of the iridium atom and the ligand through alc.-alkoxide interconversion was crucial to facilitate the transfer hydrogenation. Various ketones including alkyl aryl ketones, ketoesters, and an aryl heteroaryl ketone were competent substrates. An attractive feature of this catalysis was efficient discrimination between the alkyl and aryl substituents of the ketones, promoting hydrogenation with the identical sense of enantioselection regardless of steric demand of the alkyl substituent and thus resulting in a rare case of highly enantioselective transfer hydrogenation of tert-alkyl aryl ketones. Quantum chem. calculations revealed that the sp³-C-H/π interaction between an sp³-C-H bond of the prolinol-phosphine ligand and the aryl substituent of the ketone was crucial for the enantioselection in combination with O-H···O/sp³-C-H···O two-point hydrogen-bonding between the chiral ligand and carbonyl group.

Advanced Synthesis & Catalysis 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, Application of Phenyl(pyridin-2-yl)methanone.

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

Hanson, Susan Kloek published the artcileC-H Bond Activation by Rhodium(I) Phenoxide and Acetate Complexes: Mechanism of H-D Exchange between Arenes and Water, HPLC of Formula: 338800-13-8, the publication is Organometallics (2008), 27(7), 1454-1463, database is CAplus.

New rhodium(I) complexes (PNP)Rh(X) (PNP = 2,6-bis(di-tert-butylphosphinomethyl)pyridine) (X = OTf (1), OAc (3), OH (8), OCH₂CF₃ (9), OC₆H₅ (10), OC₆H₄NO₂ (11)) have been prepared Hydroxide complex 8 and trifluoroethoxide complex 9 undergo stoichiometric activation of benzene-d₆ to form the Ph complex (PNP)Rh(C₆D₅). Acetate and aryloxide complexes 3, 10, and 11 are active catalysts for H-D exchange between arenes and water. Control experiments indicate that the rhodium complexes are the active catalysts and that the observed exchange is not catalyzed by adventitious acid. Mechanistic studies of the H-D exchange reaction support a pathway involving dissociation of aryloxide or acetate ligand. The reaction is accelerated by added alc. and, for the acetate complex, inhibited by added sodium acetate.

Organometallics 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 C23H43NP2, HPLC of Formula: 338800-13-8.

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

Kloek, Susan M. published the artcileC-H bond activation by rhodium(I) hydroxide and phenoxide complexes, Related Products of pyridine-derivatives, the publication is Angewandte Chemie, International Edition (2007), 46(25), 4736-4738, database is CAplus and MEDLINE.

Rhodium(I) complexes of the form [(PNP)Rh(OR)](R = H, CH₂CF₃, C₆H₅; PNP = 2,6-bis[(di-tert-butylphosphino)-methyl]pyridine) have been prepared Upon thermolysis in [D₆]benzene, the hydroxide and trifluoroethoxide complexes undergo benzene activation. [(PNP)Rh(OC₆H₅)] is an active catalyst for the H/D exchange between D₂O and benzene and between H₂O and [D₈]toluene, for which exchange occurs selectively at the meta and para positions.

Angewandte Chemie, International Edition 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 C23H43NP2, Related Products of pyridine-derivatives.

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

Shaw, Arthur Y. published the artcileCharacterization of novel diaryl oxazole-based compounds as potential agents to treat pancreatic cancer, Synthetic Route of 197958-29-5, the publication is Journal of Pharmacology and Experimental Therapeutics (2009), 331(2), 636-647, database is CAplus and MEDLINE.

A series of diaryl- and fluorenone-based analogs of the lead compound UA-62784 [4-(5-(4-methoxyphenyl)oxazol-2-yl)-9H-fluoren-9-one] was synthesized with the intention of improving upon the selective cytotoxicity of UA-62784 against human pancreatic cancer cell lines with a deletion of the tumor suppressor gene deleted in pancreas cancer locus 4 (DPC-4, SMAD-4). Over 80 analogs were synthesized and tested for antitumor activity against pancreatic cancer (PC) cell lines (the PC series). Despite a structural relationship to UA-62784, which inhibits the mitotic kinesin centromere protein E (CENP-E), none of the analogs was selective for DPC-4-deleted pancreatic cancer cell lines. Furthermore, none of the analogs was a potent or selective inhibitor of four different mitotic kinesins (mitotic kinesin-5, CENP-E, mitotic kinesin-like protein-1, and mitotic centromere-associated kinesin). Therefore, other potential mechanisms of action were evaluated. A diaryl oxazole lead analog from this series, PC-046 [5-(4-methoxyphenyl)-2-(3-(3-methoxyphenyl)pyridin-4-yl) oxazole], was shown to potently inhibit several protein kinases that are overexpressed in human pancreatic cancers, including tyrosine receptor kinase B, interleukin-1 receptor-associated kinase-4, and proto-oncogene Pim-1. Cells exposed to PC-046 exhibit a cell cycle block in the S-phase followed by apoptotic death and necrosis. PC-046 effectively reduced MiaPaca-2 tumor growth in severe combined immunodeficiency mice by 80% compared with untreated controls. The plasma half-life was 7.5 h, and cytotoxic drug concentrations of >3 μM were achieved in vivo in mice. The diaryl oxazole series of compounds represent a new chem. class of anticancer agents that inhibit several types of cancer-relevant protein kinases.

Journal of Pharmacology and Experimental Therapeutics 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 C19H14N2, Synthetic Route of 197958-29-5.

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

Maust, Mark C. published the artcileSwitchable Regioselective 6-endo or 5-exo Radical Cyclization via Photoredox Catalysis, SDS of cas: 39856-58-1, the publication is Journal of the American Chemical Society (2022), 144(9), 3776-3781, database is CAplus and MEDLINE.

Here a simple method for reagent controlled regioselective radical cyclization of halogenated N-heterocycles onto pendant olefins was developed. Radical generation occurs under mild photoredox conditions with control of the regioselectivity governed by the rate of hydrogen atom transfer (HAT). Utilizing a polarity-matched thiol-based HAT agent promoted the highly selective formation of the 5-exo cyclization product. Conversely, limiting the solubility of the HAT reagent Hantzsch ester (HEH) leads to selective formation of the thermodynamically favored 6-endo product. This occurs through an initial 5-exo cyclization, with the resulting alkyl radical intermediate undergoing neophyl rearrangement to form the 6-endo product. Development of this switchable catalysis strategy allows for two modes of divergent reactivity to form either the 6-endo or 5-exo product, generating fused N-heteroaromatic/saturated ring systems.

Journal of the American Chemical Society 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, SDS of cas: 39856-58-1.

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

Fontaine, Fanny published the artcileFirst identification of boronic species as novel potential inhibitors of the Staphylococcus aureus NorA efflux pump, Recommanded Product: (6-Ethoxypyridin-3-yl)boronic acid, the publication is Journal of Medicinal Chemistry (2014), 57(6), 2536-2548, database is CAplus and MEDLINE.

Overexpression of efflux pumps is an important mechanism of bacterial resistance that results in the extrusion of antimicrobial agents outside the bacterial cell. Inhibition of such pumps appears to be a promising strategy that could restore the potency of existing antibiotics. The NorA efflux pump of Staphylococcus aureus confers resistance to a wide range of unrelated substrates, such as hydrophilic fluoroquinolones, leading to a multidrug-resistance phenotype. Here, 150 heterocyclic boronic species were evaluated for their activity against susceptible and resistant strains of S. aureus. Twenty-four hit compounds, although inactive when tested alone, were found to potentiate ciprofloxacin activity by a 4-fold increase at concentrations ranging from 0.5 to 8 μg/mL against S. aureus 1199B, which overexpresses NorA. Boron-free analogs showed no biol. activity, thus revealing that the boron atom is crucial for biol. activity. This work describes the first reported efflux pump inhibitory activity of boronic acid derivatives

Journal of Medicinal Chemistry published new progress about 612845-44-0. 612845-44-0 belongs to pyridine-derivatives, auxiliary class Pyridine,Boronic acid and ester,Ether,Boronic Acids,Boronic acid and ester, name is (6-Ethoxypyridin-3-yl)boronic acid, and the molecular formula is C7H10BNO3, Recommanded Product: (6-Ethoxypyridin-3-yl)boronic acid.

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

Takeya, Mitsue published the artcilePDGFRα⁺ subepithelial interstitial cells act as a pacemaker to drive smooth muscle of the guinea pig seminal vesicle, Quality Control of 21829-25-4, the publication is Journal of Physiology (Oxford, United Kingdom) (2022), 600(7), 1703-1730, database is CAplus and MEDLINE.

Smooth muscle cells (SMCs) of the guinea pig seminal vesicle (SV) develop spontaneous phasic contractions, Ca2+ flashes and elec. slow waves in a mucosa-dependent manner, and thus it was envisaged that pacemaker cells reside in the mucosa. Here, we aimed to identify the pacemaker cells in SV mucosa using intracellular microelectrode and fluorescence Ca2+ imaging techniques. Morphol. characteristics of the mucosal pacemaker cells were also investigated using focused ion beam/SEM tomog. and fluorescence immunohistochem. Two populations of mucosal cells developed spontaneous Ca2+ transients and elec. activity, namely basal epithelial cells (BECs) and subepithelial interstitial cells (SICs). Pancytokeratin-immunoreactive BECs were located on the apical side of the basement membrane (BM) and generated asynchronous, irregular spontaneous Ca2+ transients and spontaneous transient depolarisations (STDs). The spontaneous Ca2+ transients and STDs were not diminished by 10μM nifedipine but abolished by 10μM cyclopiazonic acid (CPA). Platelet-derived growth factor receptor α (PDGFRα)-immunoreactive SICs were distributed just beneath the basal side of the BM and developed synchronous Ca2+ oscillations and elec. slow waves, which were suppressed by 3μM nifedipine and abolished by 10μM CPA. In SV mucosal preparations in which some smooth muscle bundles remained attached, SICs and residual SMCs developed temporally correlated spontaneous Ca2+ transients. Neurobiotin injected into SICs spread not only to neighboring SICs but also to neighboring SMCs or vice versa. These results suggest that PDGFRα+ SICs electrotonically drive the spontaneous contractions of SV smooth muscle. Key points : In many visceral smooth muscle organs, spontaneous contractions are elec. driven by non-muscular pacemaker cells. In guinea pig seminal vesicles (SVs), as yet unidentified mucosal cells appear to drive neighboring smooth muscle cells (SMCs). Two populations of spontaneously active cells are distributed in the SV mucosa. Basal epithelial cells (BECs) generate asynchronous, irregular spontaneous Ca2+ transients and spontaneous transient depolarisations (STDs). In contrast, subepithelial interstitial cells (SICs) develop synchronous Ca2+ oscillations and elec. slow waves. Pancytokeratin-immunoreactive (IR) BECs are located on the apical side of the basement membrane (BM), while platelet-derived growth factor receptor α (PDGFRα)-IR SICs are located on the basal side of the BM. Spontaneous Ca2+ transients in SICs are synchronised with those in SV SMCs. Dye-coupling between SICs and SMCs suggests that SICs act as pacemaker cells to drive the spontaneous contractions of SV smooth muscle.

Journal of Physiology (Oxford, United Kingdom) published new progress about 21829-25-4. 21829-25-4 belongs to pyridine-derivatives, auxiliary class Membrane Transporter/Ion Channel,Calcium Channel, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C13H9FO2, Quality Control of 21829-25-4.

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

Kondoh, Azusa published the artcileFormal umpolung addition of phosphites to 2-azaaryl Ketones under chiral Broensted base catalysis: enantioselective protonation utilizing [1,2]-phospha-Brook rearrangement, HPLC of Formula: 91-02-1, the publication is Chemistry – A European Journal (2022), 28(42), e202201240, database is CAplus and MEDLINE.

The formal enantioselective umpolung addition of dialkyl phosphites to 2-azaaryl ketones was developed under Broensted base catalysis. The reaction involved the enantioselective protonation of the transient α-oxygenated (2-azaaryl)methyl anion generated through the 1,2-addition of the anion of dialkyl phosphite to the 2-azaaryl ketone and the subsequent [1,2]-phospha-Brook rearrangement. A chiral bis(guanidino)iminophosphorane organosuperbase efficiently catalyzed the reaction to provide enantio-enriched phosphates in high yields with good to high enantioselectivities. This is a rare example of the catalytic enantioselective protonation of transient carbanions other than enolates, constructing a trisubstituted stereogenic center α to 2-azaarenes.

Chemistry – A European Journal 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, HPLC of Formula: 91-02-1.

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

Metin, Oender published the artcileNi/Pd core/shell nanoparticles supported on graphene as a highly active and reusable catalyst for Suzuki-Miyaura cross-coupling reaction, Product Details of C11H8N2O2, the publication is Nano Research (2013), 6(1), 10-18, database is CAplus.

Monodisperse Ni/Pd core/shell nanoparticles (NPs) have been synthesized by sequential reduction of nickel(II) acetate and palladium(II) bromide in oleylamine (OAm) and trioctylphosphine (TOP). The Ni/Pd NPs have a narrow size distribution with a mean particle size of 10 nm and a standard deviation of 5% with respect to the particle diameter Mechanistic studies showed that the presence of TOP was essential to control the reductive decomposition of Ni-TOP and Pd-TOP, and the formation of Ni/Pd core/shell NPs. Using the current synthetic protocol, the composition of the Ni/Pd within the core/shell structure can be readily tuned by simply controlling the initial molar ratio of the Ni and Pd salts. The as-synthesized Ni/Pd core/shell NPs were supported on graphene (G) and used as catalyst in Suzuki-Miyaura cross-coupling reactions. Among three different kinds of Ni/Pd NPs tested, the Ni/Pd (Ni/Pd = 3/2) NPs were found to be the most active catalyst for the Suzuki-Miyaura cross-coupling of arylboronic acids with aryl iodides, bromides and even chlorides in a dimethylformamide/water mixture by using K₂CO₃ as a base at 110 °C. The G-Ni/Pd was also stable and reusable, providing 98% conversion after the 5th catalytic run without showing any noticeable Ni/Pd composition change. The G-Ni/Pd structure reported in this paper combines both the efficiency of a homogeneous catalyst and the durability of a heterogeneous catalyst, and is promising catalyst candidate for various Pd-based catalytic applications.

Nano Research 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, Product Details of C11H8N2O2.

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