Day: October 12, 2022

Oelschlegel, Manuel; Hua, Shao-An; Schmid, Lucius; Marquetand, Philipp; Baeck, Anna; Borter, Jan-Hendrik; Luecken, Jana; Dechert, Sebastian; Wenger, Oliver S.; Siewert, Inke; Schwarzer, Dirk; Gonzalez, Leticia; Meyer, Franc published the artcile< Luminescent Iridium Complexes with a Sulfurated Bipyridine Ligand: PCET Thermochemistry of the Disulfide Unit and Photophysical Properties>, SDS of cas: 366-18-7, the main research area is crystallog luminescent iridium complex sulfurated bipyridine ligand; PCET thermochem disulfide unit photophys property.

Mol. systems combining light harvesting and charge storage are receiving great attention in the context of, for example, artificial photosynthesis and solar fuel generation. As part of ongoing efforts to develop new concepts for photoinduced proton-coupled electron transfer (PCET) reactivities, we report a cyclometallated iridium(III) complex [1]+ equipped with our previously developed sulfurated bipyridine ligand S-Sbpy. A new one-step synthetic protocol for S-Sbpy is developed, starting from com. available 2,2′-bipyridine, which significantly facilitates the use of this ligand. The iridium complex [Ir(ppy)2(S-Sbpy)](PF6) ([1]PF6) features a two-electron reduction with potential inversion (|E1| > |E2|) at moderate potentials (E1 = -1.17, E2 = -1.08 V vs. Fc+/0 at 253 K), leading to a dithiolate species [1]-. Protonation with weak acids allows for determination of pKa = 23.5 in MeCN for the S-H···S- unit of [1]H. The driving forces for both the H atom and the hydride transfer are calculated to be ∼ 60 kcal mol-1 and verified exptl. by reaction with a suitable H atom and a hydride acceptor, demonstrating the ability of [1]+ to serve as a versatile PCET reagent, albeit with limited thermal stability. In the MeCN solution, an orange emission for [1]PF6 from a triplet-excited state was found. D. functional calculations and ultrafast absorption spectroscopy are used to give insight into the excited-state dynamics of the complex and suggest a significantly stretched S-S bond for the lowest triplet-state T1. The structural responsiveness of the disulfide unit is proposed to open an effective relaxation channel toward the ground state, explaining the unexpectedly short lifetime of [1]+. These insights as well as the quant. ground-state thermochem. data provide valuable information for the use of S-Sbpy-functionalized complexes and their disulfide-/dithiol-directed PCET reactivity.

Inorganic Chemistry published new progress about Attenuated-total-reflectance IR spectroscopy. 366-18-7 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2, SDS of cas: 366-18-7.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kress, Thomas J.; Moore, Larry L.; Costantino, Silvio M. published the artcile< Selective chlorinations in sulfuric acid. Synthesis of some 2-amino-5-chloro-, 2-amino-3-chloro-, and 2-amino-3,5-dichloropyridines>, Application In Synthesis of 22280-62-2, the main research area is pyridine amino chlorination; chlorination aminopyridine sulfuric acid.

Addnl. data considered in abstracting and indexing are available from a source cited in the original document. 2-Aminopyridine and a number of Me substituted 2-aminopyridines underwent selective chlorination. The chlorination of 2-aminopyridine at various H2SO4 concentrations and the distribution of chlorinated products was studied in detail. With increasing acidity dichlorination decreases, and in 72% H2SO4 only traces of dichlorination occur. The selectivity of the chlorination reaction is ascribed to differences in the rate of chlorination of protonated vs nonprotonated substrates.

Journal of Organic Chemistry published new progress about Chlorination. 22280-62-2 belongs to class pyridine-derivatives, and the molecular formula is C6H7N3O2, Application In Synthesis of 22280-62-2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Liang, Zhijie; Qiao, Yuanyuan; Li, Miaomiao; Ma, Pengtao; Niu, Jingyang; Wang, Jingping published the artcile< Two synthetic routes generate two isopolyoxoniobates based on {Nb16} and {Nb20}>, Safety of 2,2′-Bipyridine, the main research area is copper bipyridine isopolyoxoniobate preparation thermal stability; crystal structure copper bipyridine isopolyoxoniobate.

Self-assembly reactions of the Lindqvist-ion salt K7HNb6O19·13H2O, SeO2, and [Cu(2,2′-bipy)]2+ give, depending on different routes, two isopolyoxoniobates based on {Nb16} and {Nb20}, resp., which, as new members of the very limited isopolyoxoniobate family, are observed for the 1st time. Also, the solution behavior was studied to determine the stability of the {Nb16} cluster in water.

Dalton Transactions published new progress about Crystal structure. 366-18-7 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2, Safety of 2,2′-Bipyridine.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Li, Xiang; Jin, Jianbo; Chen, Pinhong; Liu, Guosheng published the artcile< Catalytic remote hydrohalogenation of internal alkenes>, Reference of 3796-23-4, the main research area is primary alkyl halide preparation palladium catalyst; terminal internal alkene hydrohalogenation.

Abstract: Primary alkyl halides have broad utility as fine chems. in organic synthesis. The direct halogenation of alkenes is one of the most efficient approaches for the synthesis of these halides. Internal alkenes, in particular mixtures of isomers from refineries, constitute readily available and inexpensive feedstock and are the most attractive starting materials for this synthesis. However, the hydrohalogenation of alkenes generally affords branched alkyl halides; there are no catalytic methods to prepare linear alkyl halides directly from internal alkenes, let alone from a mixture of alkene isomers. Here a report the remote oxidative halogenation of alkenes under palladium catalysis via which both terminal and internal alkenes yield primary alkyl halides efficiently. Engineering pyridine-oxazoline ligands by introducing a hydroxyl group is essential for achieving excellent chemo- and regioselectivity. The catalytic system is also good for the mixture of alkene isomers generated from dehydrogenation of alkanes, providing a window to investigate the high-value utilization of inexpensive alkanes.

Nature Chemistry published new progress about Alkenes Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 3796-23-4 belongs to class pyridine-derivatives, and the molecular formula is C6H4F3N, Reference of 3796-23-4.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Vydzhak, Roman N.; Panchishin, Svitlana Ya.; Kachaeva, Maryna V.; Pilyo, Stepan G.; Moskvina, Viktoriia S.; Shablykina, Olga V.; Kozytskiy, Andriy V.; Brovarets, Volodymyr S. published the artcile< Rapid synthetic approaches to libraries of diversified 1,2-dihydrochromeno[2,3-c]pyrrole-3,9-diones and 3-(2-hydroxyphenyl)-4,5-dihydropyrrolo[3,4-c]pyrazol-6(1H)-ones>, Application of C6H8N2, the main research area is dihydrochromenopyrrole dione preparation; hydroxyphenyl dihydropyrrolopyrazolone preparation; Chromeno[2,3-c]pyrroles; Combinatorial library; Dihydrochromeno[2,3-c]pyrrole-3,9-diones; Dihydropyrrolo[3,4-c]pyrazol-6(1H)-ones; Multicomponent cyclization.

An efficient and practical synthetic procedure for libraries of diversified 1,2-dihydrochromeno[2,3-c]pyrrole-3,9-diones I [R =H, 6,7-di-Me, 7-F, etc.; R1 = n-Pr, CH2CH2OH, 2-furylmethyl, etc.; Ar = Ph, 4-MeC6H4, 3,4,5-tri-MeOC6H2, etc.] using a multicomponent process was presented. A convenient synthetic procedure for obtaining functionalized 3-(2-hydroxyphenyl)-4,5-dihydropyrrolo[3,4-c]pyrazol-6(1H)-ones II [R2 = H, 3,5-di-Me, 4-Me-5-Cl, etc.; R3 = 4-BrC6H4, 2-OHC6H4, 3-MeO-4-OHC6H3, etc.; R4 = n-Pr, CH2CH2OH, 2-ClC6H4CH2, etc.] via ring-opening strategy was developed. This protocol was found to be compatible with a wide range of substituents and paves the way for the practical synthesis of title compounds with a broad range of substituents under mild condition. The products could be easily isolated by crystallization without the use of chromatog.

Molecular Diversity published new progress about Amines Role: RCT (Reactant), RACT (Reactant or Reagent). 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, Application of C6H8N2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Pegu, David; Singh, Ngangbam Bedamani published the artcile< Quantum chemical calculations of molecular structure, electronic, thermodynamic and non-linear optical properties of 2-amino-3-nitro-6-methyl pyridine>, Name: 2-Amino-3-nitro-6-picoline, the main research area is amino nitro methyl pyridine mol structure hyperpolarizability.

In the present study, we report a theor. study on mol. structure, electronic and thermodynamical properties of 2-amino-3-nitro-6-Me pyridine (2A3N6MP) by using ab initio Hartree Fock (HF) and d. functional theory (DFT) methods employing B3LYP exchange correlation with 6-311++G(d,p) basis set. The ground state mol. geometrical parameters, have been calculated and compared with available reported values. The calculated HOMO and LUMO energy shows that charge transfer takes place within the mol. and the mol. is chem. soft mol. The dipole moment, linear polarizability and first hyperpolarizability values were also computed. Finally the temperature dependence thermodn. properties were also determined and interpreted.

International Journal of Advanced Research published new progress about Dipole moment. 21901-29-1 belongs to class pyridine-derivatives, and the molecular formula is C6H7N3O2, Name: 2-Amino-3-nitro-6-picoline.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kuzuya, Masayuki; Noguchi, Akihiro; Mano, Eiichi; Okuda, Takachiyo published the artcile< The structure-reactivity-chemoselectivity relationship on the reactions of 1-unsubstituted tautomeric 2-pyridones with benzyne>, Product Details of C5H4ClNO, the main research area is tautomerism pyridone reaction benzyne.

The effect of tautomerism of 2-pyridones on the products obtained in reaction with benzyne was studied. Both Diels-Alder and Michael-type adducts were formed. The Diels-Alder reactivities were correlated with HOMO energy levels of the 2-pyridone form; the yields of the Michael-type adducts were associated with the tautomeric equilibrium Substituent effects on the tautomerism were discussed.

Bulletin of the Chemical Society of Japan published new progress about CNDO/2 (molecular orbital method). 73018-09-4 belongs to class pyridine-derivatives, and the molecular formula is C5H4ClNO, Product Details of C5H4ClNO.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Lopez Quezada, Landys; Li, Kelin; McDonald, Stacey L.; Nguyen, Quyen; Perkowski, Andrew J.; Pharr, Cameron W.; Gold, Ben; Roberts, Julia; McAulay, Kathrine; Saito, Kohta; Somersan Karakaya, Selin; Javidnia, Prisca Elis; Porras de Francisco, Esther; Amieva, Manuel Marin; Diaz, Sara Palomo; Mendoza Losana, Alfonso; Zimmerman, Matthew; Liang, Hsin-Pin Ho; Zhang, Jun; Dartois, Veronique; Sans, Stephanie; Lagrange, Sophie; Goullieux, Laurent; Roubert, Christine; Nathan, Carl; Aube, Jeffrey published the artcile< Dual-Pharmacophore Pyrithione-Containing Cephalosporins Kill Both Replicating and Nonreplicating Mycobacterium tuberculosis>, Electric Literature of 3811-73-2, the main research area is pyrithione containing cephalosporin Mycobacterium replication; antimycobacterial; cephalosporin; pyrithione; tuberculosis; β-lactamase.

The historical view of β-lactams as ineffective antimycobacterials has given way to growing interest in the activity of this class against Mycobacterium tuberculosis (Mtb) in the presence of a β-lactamase inhibitor. However, most antimycobacterial β-lactams kill Mtb only or best when the bacilli are replicating. Here, a screen of 1904 β-lactams led to the identification of cephalosporins substituted with a pyrithione moiety at C3′ that are active against Mtb under both replicating and nonreplicating conditions, neither activity requiring a β-lactamase inhibitor. Studies showed that activity against nonreplicating Mtb required the in situ release of the pyrithione, independent of the known class A β-lactamase, BlaC. In contrast, replicating Mtb could be killed both by released pyrithione and by the parent β-lactam. Thus, the antimycobacterial activity of pyrithione-containing cephalosporins arises from 2 mechanisms that kill mycobacteria in different metabolic states.

ACS Infectious Diseases published new progress about Blood plasma. 3811-73-2 belongs to class pyridine-derivatives, and the molecular formula is C5H4NNaOS, Electric Literature of 3811-73-2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Yu, Hsien-Cheng; Islam, Shahidul M.; Mankad, Neal P. published the artcile< Cooperative Heterobimetallic Substrate Activation Enhances Catalytic Activity and Amplifies Regioselectivity in 1,4-Hydroboration of Pyridines>, Application of C6H4F3N, the main research area is cooperative catalyst NHC copper iron half sandwich regioselective borylation; pyridine regioselective borylation cooperative copper iron imidazolylidene catalyst; dihydropyridine boronate preparation regioselective hydroboration pyridine cooperative bimetallic catalyst.

Regioselective 1,4-hydroboration of pyridine derivatives and quinoline with pinacolborane is catalyzed efficiently by the heterobinuclear catalyst, (IPr)CuFeCp(CO)2, at only 2 mol % loading, providing access to valuable 1,4-dihydropyridine (1,4-DHP) products. A variety of reactive functional groups are tolerated in the pyridine 3-position, and sufficient catalytic activity was obtained for reduction of sterically hindered cases such as 3,5-disubstituted pyridines and even 4-substituted pyridines. Mechanistic experiments indicate that the superior catalytic activity and 1,4-regioselectivity of the Cu/Fe heterobinuclear catalyst, compared to the corresponding mononuclear Cu catalyst, is derived from biphilic cooperativity of two key catalytic intermediates: electrophilic CpFe(CO)2(Bpin) activates the pyridine substrates toward regioselective nucleophilic addition by (IPr)CuH.

ACS Catalysis published new progress about Boronic acids, esters Role: PEP (Physical, Engineering or Chemical Process), RCT (Reactant), SPN (Synthetic Preparation), PROC (Process), RACT (Reactant or Reagent), PREP (Preparation). 3796-23-4 belongs to class pyridine-derivatives, and the molecular formula is C6H4F3N, Application of C6H4F3N.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Akiu, Mayuko; Tsuji, Takashi; Sogawa, Yoshitaka; Terayama, Koji; Yokoyama, Mika; Tanaka, Jun; Asano, Daigo; Sakurai, Ken; Sergienko, Eduard; Sessions, E. Hampton; Gardell, Stephen J.; Pinkerton, Anthony B.; Nakamura, Tsuyoshi published the artcile< Discovery of 1-[2-(1-methyl-1H-pyrazol-5-yl)-[1,2,4]triazolo[1,5-a]pyridin-6-yl]-3-(pyridin-4-ylmethyl)urea as a potent NAMPT (nicotinamide phosphoribosyltransferase) activator with attenuated CYP inhibition>, Category: pyridine-derivatives, the main research area is nicotinamide phosphoribosyltransferase activator pyrazolyltriazolopyridine pyridinylmethyl urea; CYP inhibition; LogD; NAD(+); NAMPT activators; Triazolopyridines.

Nicotinamide phosphoribosyltransferase (NAMPT) catalyzes the rate-limiting step of the NAD+ salvage pathway. Since NAD+ plays a pivotal role in many biol. processes including metabolism and aging, activation of NAMPT is an attractive therapeutic target for treatment of diverse array of diseases. Herein, we report the continued optimization of novel urea-containing derivatives which were identified as potent NAMPT activators. Early optimization of HTS hits afforded compound 12 (I) , with a triazolopyridine core, as a lead compound CYP direct inhibition (DI) was identified as an issue of concern, and was resolved through modulation of lipophilicity to culminate in 1-[2-(1-methyl-1H-pyrazol-5-yl)-[1,2,4]triazolo[1,5-a]pyridin-6-yl]-3-(pyridin-4-ylmethyl)urea (21, II), which showed potent NAMPT activity accompanied with attenuated CYP DI towards multiple CYP isoforms.

Bioorganic & Medicinal Chemistry Letters published new progress about Biological permeation. 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, Category: pyridine-derivatives.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem