Day: December 7, 2022

Arnold, Eric P. published the artcileOxidative Cyclization Approach to Benzimidazole Libraries, COA of Formula: C6H8N2, the publication is ACS Combinatorial Science (2020), 22(1), 1-5, database is CAplus and MEDLINE.

An efficient approach to the parallel synthesis of benzimidazoles from anilines is described. Library approaches to vary the N1 and C2 vectors of benzimidazoles are well established; however, C4-C7 variation has traditionally relied on 1,2-dianiline building blocks, providing limited chem. space coverage. We have developed an amidine formation/oxidative cyclization sequence that enables anilines as a diversity set for benzimidazole C4-C7 SAR generation in parallel format. The amidine annulation was achieved using PIDA or Cu-mediated oxidation to access both N-H and N-alkyl benzimidazoles. This library protocol has now been utilized for analog production in four medicinal chem. projects. Addnl., the synthesis of aza-benzimidazoles from aminopyridines was achieved via an analogous sequence.

ACS Combinatorial Science 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, COA of Formula: C6H8N2.

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

Okazaki, Shiho published the artcileIdentification of anti-HIV agents with a novel benzo[4,5]isothiazolo[2,3-a]pyrimidine scaffold, Safety of 2-Pyridinylboronic acid, the publication is Bioorganic & Medicinal Chemistry (2015), 23(7), 1447-1452, database is CAplus and MEDLINE.

3,4-Dihydro-2H-benzo[4,5]isothiazolo[2,3-a]pyrimidine is a newly identified antiviral agent against human immunodeficiency virus type 1 (HIV-1) infection, derived from 3,4-dihydro-2H,6H-pyrimido[1,2-c][1,3]benzothiazin-6-imine (PD 404182). The introduction of the hydrophobic 8-aryl substituent on the benzene substructure improved its anti-HIV activity, resulting in the identification of 6-fold more potent analogs. In addition, it was demonstrated that these isothiazolopyrimidine derivatives exert anti-HIV effects at an early stage of viral infection.

Bioorganic & Medicinal Chemistry 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, Safety of 2-Pyridinylboronic acid.

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

Arashiba, Kazuya published the artcileA molybdenum complex bearing PNP-type pincer ligands leads to the catalytic reduction of dinitrogen into ammonia, Application In Synthesis of 338800-13-8, the publication is Nature Chemistry (2011), 3(2), 120-125, database is CAplus and MEDLINE.

The synthesis of transition metal-dinitrogen complexes and the stoichiometric transformation of their coordinated dinitrogen into ammonia and hydrazine have been the subject of considerable research, with a view to achieving nitrogen fixation under ambient conditions. Since a single example in 2003, no examples have been reported of the catalytic conversion of dinitrogen into ammonia under ambient conditions. The dimolybdenum-dinitrogen complex bearing PNP pincer ligands was found to work as an effective catalyst for the formation of ammonia from dinitrogen, with 23 equivalent of ammonia being produced with the catalyst (12 equivalent of ammonia are produced based on the molybdenum atom of the catalyst). This is another successful example of the catalytic and direct conversion of dinitrogen into ammonia under ambient reaction conditions. We believe that the results described in this Article provide valuable information with which to develop a more effective nitrogen-fixation system under mild reaction conditions.

Nature Chemistry 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, Application In Synthesis of 338800-13-8.

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

Ishida, Naoki published the artcileStereoselective synthesis of trisubstituted alkenylboranes by palladium-catalysed reaction of alkynyltriarylborates with aryl halides, Name: Triphenyl(pyridin-1-ium-1-yl)borate, the publication is Chemical Communications (Cambridge, United Kingdom) (2007), 4381-4383, database is CAplus and MEDLINE.

The palladium-catalyzed reaction of alkynyltriarylborates with aryl halides afforded trisubstituted alkenylboranes, in which two different aryl groups were installed across the carbon-carbon double bond in a cis arrangement.

Chemical Communications (Cambridge, United Kingdom) published new progress about 971-66-4. 971-66-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene, name is Triphenyl(pyridin-1-ium-1-yl)borate, and the molecular formula is C23H20BN, Name: Triphenyl(pyridin-1-ium-1-yl)borate.

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

Katakis, D. published the artcilePhotocatalytic splitting of water: increase in conversion and energy storage efficiency, Computed Properties of 47369-00-6, the publication is Journal of Photochemistry and Photobiology, A: Chemistry (1994), 81(2), 103-6, database is CAplus.

The yield of the photocatalytic splitting of water using tris-[1-(4-methoxyphenyl)-2-phenyl-1,2-ethylenodithiolenic-S,S’]tungsten as a photocatalyst-catalyst increases by more than three fold on going from 20 to 70°, and there is no indication that the effect levels off at this temperature The intensity of light (within the error limits of our experiments) does not have an appreciable effect. The nature of the reversible electron acceptor also influences the energy storage efficiency, e.g. 1,1-dibenzyl-4,4′-bipyridinium dichloride gives an energy storage efficiency approx. 10% higher than methylviologen. The energy storage efficiency also depends on the presence of electron donors; if Ph₃N is added, the energy storage efficiency increases by 20%. With EDTA the results are even more spectacular; there is a two-fold increase, but only initially. At longer times the system is unstable. Overall light energy storage efficiencies can be as high as 7%, and the expectations for further improvement are very good.

Journal of Photochemistry and Photobiology, A: Chemistry published new progress about 47369-00-6. 47369-00-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Benzene,Organic ligands for MOF materials,Nitrogen containing MOF ligands,Nitrogen containing MOF ligands, name is 1,1′-Diphenyl-[4,4′-bipyridine]-1,1′-diium chloride, and the molecular formula is C22H18Cl2N2, Computed Properties of 47369-00-6.

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

Palav, Amey published the artcileRapid, chemoselective and mild oxidation protocol for alcohols and ethers with recyclable N-chloro-N-(phenylsulfonyl)benzenesulfonamide, Synthetic Route of 91-02-1, the publication is Tetrahedron Letters (2021), 153094, database is CAplus.

A sulfonimide reagent, N-chloro-N-(phenylsulfonyl)benzenesulfonamide (NCBSI) was identified as a mild and selective oxidant. Without activation, the reagent was proved to oxidize primary and secondary alcs. as well as their sym. and mixed ethers to corresponding aldehydes and ketones. With recoverable PS-TEMPO catalyst, selective oxidation over chlorination of primary and secondary alcs. and their ethers with electron-donating substituents was achieved. The reagent precursor of NCBSI was recovered quant. and can be reused for synthesizing NCBSI.

Tetrahedron Letters 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, Synthetic Route of 91-02-1.

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

Todeschini, A.R. published the artcile2-Pyridylarylhydrazone derivatives, a new class of platelet aggregation inhibitors, Safety of 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, the publication is Brazilian Journal of Medical and Biological Research (1996), 29(3), 389-93, database is CAplus and MEDLINE.

A series of 2-pyridylarylhydrazone derivatives was synthesized and compared with a previously reported pyrazole series, i.e., 4-acylpyrazolylarylhydrazone and 5-pyrazolylarylhydrazone, which present antiplatelet aggregation activity. The structures of these pyridylarylhydrazone derivatives were designed on the basis of the known bioisosteric relation of the heteroaromatic ring. The antiplatelet aggregation activity was measured in vitro on citrated platelet-rich rabbit plasma in which aggregation was induced with 5 μM ADP, 5 μg/mL collagen and 200 μM arachidonic acid. Eighteen compounds belonging to the pyridine series were tested at 1 mM concentration and none inhibited ADP-induced rabbit platelet aggregation. 2-(2-Formylfurane)pyridylhydrazone exhibited a highly potent inhibitory activity on arachidonic acid-induced aggregation, with an IC₅₀ of 0.35 μM. These results suggest that the hydrazone unit and the 2-furyl moiety of the arylhydrazone framework are important pharmacophores for antiplatelet activity.

Brazilian Journal of Medical and Biological Research published new progress about 2215-33-0. 2215-33-0 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine, name is 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, and the molecular formula is C15H20O6, Safety of 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine.

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

Semproni, Scott P. published the artcileFour-Coordinate Cobalt Pincer Complexes: Electronic Structure Studies and Ligand Modification by Homolytic and Heterolytic Pathways, Quality Control of 338800-13-8, the publication is Journal of the American Chemical Society (2014), 136(25), 9211-9224, database is CAplus and MEDLINE.

A family of cobalt chloride, Me, acetylide and hydride complexes bearing both intact and modified tert-Bu substituted bis(phosphino)pyridine pincer ligands has been synthesized and structurally characterized and their electronic structures evaluated. Treatment of the unmodified compounds with the stable nitroxyl radical, TEMPO (2,2,6,6-tetramethylpiperidin-1-yloxidanyl) resulted in immediate H- atom abstraction from the benzylic position of the chelate yielding the corresponding modified pincer complexes, (^tBumPNP)CoX (X = H, CH₃, Cl, CCPh). Thermolysis of the Me and hydride derivatives, (^tBuPNP)CoCH₃ and (^tBuPNP)CoH, at 110° also resulted in pincer modification by H atom loss while the chloride and acetylide derivatives proved inert. The relative ordering of benzylic C-H bond strengths was corroborated by H atom exchange experiments between appropriate intact and modified pincer complexes. The electronic structures of the modified compounds, (^tBumPNP)CoX were established by EPR spectroscopy and DFT computations and are best described as low spin Co(II) complexes with no evidence for ligand centered radicals. The electronic structures of the intact complexes, (^tBuPNP)CoX were studied computationally and bond dissociation free energies of the benzylic C-H bonds were correlated to the identity of the X-type ligand on cobalt where pure σ donors such as hydride and Me produce the weakest C-H bonds. Comparison to a rhodium congener highlights the impact of the energetically accessible one-electron redox couple of the first row metal ion in generating weak C-H bonds in remote positions of the supporting pincer ligand.

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 0, Quality Control of 338800-13-8.

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

Nishide, Shigenori published the artcileImproved determination of betahistine mesylate, Synthetic Route of 54856-23-4, the publication is Yakugaku Zasshi (1983), 103(11), 1180-4, database is CAplus and MEDLINE.

An improved method for the determination of betahistine mesylate (I) [54856-23-4] in tablets was developed by the use of UV spectrophotometry at 260 nm. The determination of in aqueous solutions were affected by pH and temperature The measurement of the mesylate in 0.1 N sulfuric acid instead of water produced more accurate results.

Yakugaku Zasshi published new progress about 54856-23-4. 54856-23-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Amine,Inhibitor,Inhibitor, name is N-Methyl-2-(pyridin-2-yl)ethan-1-amine dimethanesulfonate, and the molecular formula is C10H20N2O6S2, Synthetic Route of 54856-23-4.

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

Kowol, Christian R. published the artcileImpact of Stepwise NH₂-Methylation of Triapine on the Physicochemical Properties, Anticancer Activity, and Resistance Circumvention, Safety of 2-Bromopyridin-3-amine, the publication is Journal of Medicinal Chemistry (2016), 59(14), 6739-6752, database is CAplus and MEDLINE.

One of the most promising classes of iron chelators are α-N-heterocyclic thiosemicarbazones with Triapine as the most prominent representative. In several clin. trials Triapine showed anticancer activity against hematol. diseases, however, studies on solid tumors failed due to widely unknown reasons. Some years ago, it was recognized that “terminal dimethylation” of thiosemicarbazones can lead to a more than 100-fold increased activity, probably due to interactions with cellular copper depots. To better understand the structural requirements for the switch to nanomolar cytotoxicity, we systematically synthesized all eight possible N-methylated derivatives of Triapine and investigated their potential against Triapine-sensitive as well as -resistant cell lines. While only the “completely” methylated compound exerted nanomolar activity, the data revealed that all compounds with at least one N-dimethylation were not affected by acquired Triapine resistance. In addition, these compounds were highly synergistic with copper treatment accompanied by induction of reactive oxygen species and massive necrotic cell death.

Journal of Medicinal Chemistry 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, Safety of 2-Bromopyridin-3-amine.

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