Month: October 2022

Reusch, Engelbert; Holzmeier, Fabian; Gerlach, Marius; Fischer, Ingo; Hemberger, Patrick published the artcile< Decomposition of Picolyl Radicals at High Temperature: A Mass Selective Threshold Photoelectron Spectroscopy Study>, HPLC of Formula: 3731-53-1, the main research area is picolyl radical decomposition mechanism potential energy surface; ionization energy; photoelectron spectroscopy; pyrolysis; radicals; synchrotron radiation.

The reaction products of the picolyl radicals at high temperature were characterized by mass-selective threshold photoelectron spectroscopy in the gas phase. Aminomethylpyridines were pyrolyzed to initially produce picolyl radicals (m/z=92). At higher temperatures further thermal reaction products are generated in the pyrolysis reactor. All compounds were identified by mass-selected threshold photoelectron spectroscopy and several hitherto unexplored reactive mols. were characterized. The mechanism for several dissociation pathways was outlined in computations. The spectrum of m/z=91, resulting from hydrogen loss of picolyl, shows four isomers, two ethynyl pyrroles with adiabatic ionization energies (IEad) of 7.99 eV (2-ethynyl-1H-pyrrole) and 8.12 eV (3-ethynyl-1H-pyrrole), and two cyclopentadiene carbonitriles with IE’s of 9.14 eV (cyclopenta-1,3-diene-1-carbonitrile) and 9.25 eV (cyclopenta-1,4-diene-1-carbonitrile). A second consecutive hydrogen loss forms the cyanocyclopentadienyl radical with IE’s of 9.07 eV (T0) and 9.21 eV (S1). This compound dissociates further to acetylene and the cyanopropynyl radical (IE=9.35 eV). Furthermore, the cyclopentadienyl radical, penta-1,3-diyne, cyclopentadiene and propargyl were identified in the spectra. Computations indicate that dissociation of picolyl proceeds initially via a resonance-stabilized seven-membered ring.

Chemistry – A European Journal published new progress about Adiabatic ionization potential. 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, HPLC of Formula: 3731-53-1.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Knight, Brian J.; Tolchin, Zachary A.; Smith, Joel M. published the artcile< A predictive model for additions to N-alkyl pyridiniums>, Recommanded Product: 3-(Methoxycarbonyl)pyridine, the main research area is pyridine Grignard methyl triflate regioselective dearomative addition; dihydropyridine preparation.

Disclosed in this communication is a thorough study on the dearomative addition of organomagnesium nucleophiles to N-alkyl pyridinium electrophiles. The regiochem. outcomes have observable and predictable trends associated with the substituent patterns on the pyridinium electrophile. Often, the substituent effects can be either additive, giving high selectivities, or ablative, giving competing outcomes. Addnl., the nature of the organometallic nucleophilic component was also investigated for its role in the regioselective outcome. The effects of either reactive component are important to both the overall reactivity and site of nucleophilic addition The utility of these observed trends is demonstrated in a concise, dearomative synthesis of a tricyclic compound shown to have insecticidal activity.

Chemical Communications (Cambridge, United Kingdom) published new progress about Dearomatization. 93-60-7 belongs to class pyridine-derivatives, and the molecular formula is C7H7NO2, Recommanded Product: 3-(Methoxycarbonyl)pyridine.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kanno, Sanae; Hirano, Seishiro; Kato, Hideaki; Fukuta, Mamiko; Mukai, Toshiji; Aoki, Yasuhiro published the artcile< Benzalkonium chloride and cetylpyridinium chloride induce apoptosis in human lung epithelial cells and alter surface activity of pulmonary surfactant monolayers.>, SDS of cas: 123-03-5, the main research area is lung epithelial cell benzalkonium cetylpyridinium chloride apoptosis; A549 alveolar epithelial cell; Apoptosis; Langmuir-blodgett monolayer; Pulmonary surfactant; Quaternary ammonium disinfectant; Surface pressure/trough area isotherm.

To examine whether BAC and CPC aerosols deposited in the alveolar region alter pulmonary function, we studied the effects on pulmonary surfactant using two-step in vitro models; cytotoxicity using A549 alveolar epithelial cell and changes in surface activity of the pulmonary surfactant monolayer using both Surfacten and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). Cell viability was decreased with BAC and CPC dose-dependently. A comparison of cytotoxicity among BAC homologues with different length of alkyl chain showed that C16-BAC, which has the longest alkyl chain, was more cytotoxic than C12- or C14-BAC. Caspase-3/7 activity and cleaved form of caspase-3 and PARP were increased in BAC- and CPC-exposed cells. The elevated caspase-3/7 activity and their cleaved active forms were abolished by caspase-3-inhibitor. The collapse pressure diminished with increasing concentration of CPC. Topog. images indicated that BAC and CPC resulted in smaller condensed lipid domains compared to the control. Conversely, PC without hydrocarbon tail group, showed no cytotoxicity and did not change the isotherms and AFM images. These results indicate that BAC and CPC cause cell death via caspase-3-dependent apoptotic pathway in A549 cells and alter the alveolar surfactant activity. These effects can be attributed to the long alkyl chain of BAC and CPC.

Chemico-Biological Interactions published new progress about Apoptosis. 123-03-5 belongs to class pyridine-derivatives, and the molecular formula is C21H38ClN, SDS of cas: 123-03-5.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kang, Ji-Hoon; Park, Jun-Beom; Song, Kyung Bin published the artcile< Inhibitory activities of quaternary ammonium surfactants against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes inoculated on spinach leaves>, Application of C21H38ClN, the main research area is Escherichia Salmonella Listeria quaternary ammonium surfactant disinfection food safety.

Antimicrobial activities of quaternary ammonium surfactants (QAS) have been reported, but the effects of various QAS on the disinfection of foodborne pathogens on fresh produce have not been compared. Thus, the objective of this study was to determine the most effective QAS to be used as a disinfectant for fresh produce to replace chlorine-based sanitizers through comparison of inhibitory activities of the various QAS (benzalkonium chloride, benzethonium chloride, cetylpyridinium chloride, cetyltrimethylammonium bromide, tetraethylammonium bromide) against Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes inoculated on spinach leaves. Among the QAS used in this study, cetylpyridinium chloride (CPC) exhibited maximum inhibitory activity because of its high pos. ζ-potential value (67.23 mV), resulting in 3.33, 3.28, and 4.54 log-reductions against E. coli O157:H7, S. Typhimurium, and L. monocytogenes, resp. The microbial count reductions by CPC were higher than those obtained by NaOCl treatment at 80 mg/L. The CPC treatment produced fewer injured cells than NaOCl treatment. In addition, CPC treatment did not alter the surface color and weight loss of spinach samples during storage. Thus, these results suggest that CPC could be used as an effective sanitizer to improve the microbial safety of spinach leaves.

LWT–Food Science and Technology published new progress about Escherichia coli. 123-03-5 belongs to class pyridine-derivatives, and the molecular formula is C21H38ClN, Application of C21H38ClN.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kowalkowska-Zedler, D.; Dolega, A.; Nedelko, N.; Lyszczek, R.; Aleshkevych, P.; Demchenko, I.; Luczak, J.; Slawska-Waniewska, A.; Pladzyk, A. published the artcile< Structural, magnetic and spectral properties of tetrahedral cobalt(II) silanethiolates: a variety of structures and manifestation of field-induced slow magnetic relaxation>, Name: Pyridin-4-ylmethanamine, the main research area is cobalt silanethiolate aminopyridine aminomethylpyridine complex preparation magnetic property; thermal stability cobalt silanethiolate aminopyridine aminomethylpyridine; crystal structure cobalt silanethiolate aminopyridine aminomethylpyridine.

Blue crystals of five heteroleptic cobalt(II) silanethiolates 1-5 have been obtained by the reaction of [Co{SSi(tBuO)3}2(NH3)]2 with aminopyridines and aminomethylpyridines at an appropriate molar ratio and their structural, spectral, thermal and magnetic properties have been established and described. All complexes 1-5 contain Co(II) ions in a tetrahedral CoN2S2 environment formed by (tBuO)3SiS- residues and pyridines and present variable structures. Complexes 1-3 are mononuclear [Co{SSi(tBuO)3}2(L1)2] (L1 = 2-aminopyridine 2AP, 3-aminopyridine 3AP, and 4-aminopyridine 4AP). The application of 3AMP and 4AMP (3-aminomethylpyridine and 4-aminomethylpyridine) allows either dinuclear complex 4 [Co{SSi(tBuO)3}2(μ-3AMP)]2 or 1D coordination polymer 5 with the formula of [Co{SSi(tBuO)3}2(μ-4AMP)]n to be obtained. The mol. structures of 1-5 were determined by single-crystal X-ray and powder diffraction, UV-vis and FTIR spectrocopy for solid samples and their thermal properties were characterized by TG-DSC and TG-FTIR methods. The dc and ac magnetic and EPR studies of polycrystalline samples have been performed. For all complexes, the obtained data show a behavior typical of paramagnetic high-spin Co(II) ions in a tetrahedral geometry, with a considerable contribution of the ZFS effect in a low temperature range. All complexes were also probed for SIM behavior. The modeling of the magnetic and EPR data was done for samples 1, 3, 4 and 5 to estimate ZFS parameters. The obtained results imply a neg. value of the axial parameter D in complex 4 and pos. D values for the rest of the compounds A comparative magneto-structural anal. of complexes 4 and 5 points to the high sensitivity of the single-ion magnetic anisotropy of tetrahedral Co(II) complexes to subtle changes in the first and second coordination spheres of Co(II) ions.

Dalton Transactions published new progress about Aminopyridines Role: PEP (Physical, Engineering or Chemical Process), PRP (Properties), SPN (Synthetic Preparation), PROC (Process), PREP (Preparation) (cobalt complexes). 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, Name: Pyridin-4-ylmethanamine.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Dong, Zhen; Liu, Junzi; Wen, Di; Zhai, Maolin; Zhao, Long published the artcile< Aminomethylpyridine isomers functionalized cellulose microspheres for TcO-4/ReO-4 uptake: Structure-properties relationship and their application in different aquatic systems>, Safety of Pyridin-4-ylmethanamine, the main research area is cellulose aminomethylpyridine isomer technetium rhenium oxide adsorption; (99)Tc; Adsorption mechanism; ReO(4)(-); Removal; Structure-properties relationship.

Technetium-99 (99Tc) is a long-lived radioactive nuclide that poses great threat to environment, hence selective removal of 99Tc from aquatic system is always an issue. Aminomethylpyridine (AMP) equipped with pyridine and amino, is a promising receptor for TcO4- and its surrogate ReO4-, thus it is of interest to explore and understand the structure-properties relationship of ReO4- adsorption related to n-AMP structure that differ in amino Me position. In this work, three n-AMP functionalized cellulose microspheres (n-AMPR, n = 2, 3, 4) were synthesized and employed for TcO4-/ReO4- uptake. The effect of aminomethyl position on adsorption properties of n-AMPR for ReO4- were investigated and compared. Adsorption kinetics and adsorption isotherm showed that adsorption speed and adsorption capacity were in order of 3-AMPR > 2-AMPR > 4-AMPR. DFT calculation verified that the adsorption of ReO4- by n-AMPR was attributed to electrostatic interaction and hydrogen bonding interaction, the order of adsorption abilities of n-AMPR was due to that steric effect and hydrogen bond collaborated in stabilizing n-AMPR-ReO4- complexes. The column experiments demonstrated that 3-AMPR can be selectively remove ReO4- from simulated groundwater. More importantly, 99Tc column experiments showed that 3-AMPR had a better ability for actual radioactive TcO4-.

Journal of Hazardous Materials published new progress about Adsorption. 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, Safety of Pyridin-4-ylmethanamine.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Huang, Zhiyong; Wang, Dan; Long, Cheng-Yu; Li, Shen-Huan; Wang, Xue-Qiang; Tan, Weihong published the artcile< Regulating the Anticancer Efficacy of Sgc8-Combretastatin A4 Conjugates: A Case of Recognizing the Significance of Linker Chemistry for the Design of Aptamer-Based Targeted Drug Delivery Strategies>, Recommanded Product: 1,2-Di(pyridin-2-yl)disulfane, the main research area is aptamer targeted drug delivery anticancer efficacy cytotoxicity cell viability.

The unique merits of aptamers, including specificity, high binding affinity, easy cell internalization, and rapid tissue accumulation abilities, have led aptamer-drug conjugates to evolve into one of the most attractive strategies for targeted drug delivery purposes. Nevertheless, the critical role of linkers in regulating anticancer efficacy of these conjugates, especially those engineered by automated modular synthesis techniques, has been rarely explored. In this work, we utilized Sgc8c aptamer and combretastatin A4 to develop three conjugates with either a phosphodiester bond linker, a disulfide bond linker, or a carbamate linker to study their payload release mechanisms and the influence on anticancer efficacy. These investigations allowed us to identify the unique activation pathway of the phosphodiester bond linker that is activated by both nucleophilic attack of glutathione and degradation caused by phosphodiesterase, which is highly associated with the higher cytotoxicity of the conjugate. Importantly, the understanding of the chem. of phosphodiester bond linker activation allowed us to further design another XQ-2d-CA4 conjugate that can induce pancreatic cancer cells apoptosis in a more efficient manner.

Journal of the American Chemical Society published new progress about Antitumor agents. 2127-03-9 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2S2, Recommanded Product: 1,2-Di(pyridin-2-yl)disulfane.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Mittelbach, Martin published the artcile< An easy and convenient synthesis of 6-methyl-4(1H)-pyridone-3-carboxylic acid>, Reference of 86129-63-7, the main research area is nicotinic acid dihydro oxo methyl.

The title acid (I) was prepared from a nicotinic acid derivative Et 2,4-dichloro-6-methylnicotinate was treated with Na and R1OH (R1 = Me, Et), the alkoxy analog products II were subjected to reductive dechlorination, and the products were hydrolyzed by HCl to give I.

Synthesis published new progress about 86129-63-7. 86129-63-7 belongs to class pyridine-derivatives, and the molecular formula is C9H9Cl2NO2, Reference of 86129-63-7.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Dedeian, K.; Djurovich, P. I.; Garces, F. O.; Carlson, G.; Watts, R. J. published the artcile< A new synthetic route to the preparation of a series of strong photoreducing agents: fac-tris-ortho-metalated complexes of iridium(III) with substituted 2-phenylpyridines>, Related Products of 370878-69-6, the main research area is photoreducing agent phenylpyridine iridium complex; pyridylbenzene iridium complex.

Reaction of 2-phenylpyridine (Hppy) with Ir(acac)3 (acac = acetylacetonato) in refluxing glycerol gives the fac-tris-ortho-metalate of Ir(III), fac-Ir(ppy)3 in high yield (45%). Phenyl-ring-substituted derivatives of 2-phenylpyridine (R-Hppy) were prepared by cross-coupling of 2-bromopyridine with substituted bromobenzenes. These react with Ir(acac)3 in a manner analogous to Hppy to give similarly high yields (40-75%) of their resp. tris-ortho-metalates, fac-Ir(R-ppy)3.

Inorganic Chemistry published new progress about Electrochemistry. 370878-69-6 belongs to class pyridine-derivatives, and the molecular formula is C33H21F3IrN3, Related Products of 370878-69-6.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kalindjian, S. Barret; Kadnur, Sanjay V.; Hewson, Christopher A.; Venkateshappa, Chandregowda; Juluri, Suresh; Kristam, Rajendra; Kulkarni, Bheemashankar; Mohammed, Zainuddin; Saxena, Rohit; Viswanadhan, Vellarkad N.; Aiyar, Jayashree; McVey, Donna published the artcile< A New Series of Orally Bioavailable Chemokine Receptor 9 (CCR9) Antagonists; Possible Agents for the Treatment of Inflammatory Bowel Disease>, Quality Control of 56622-54-9, the main research area is dioxoisoindoline derivative preparation CCR9 antagonist inflammatory bowel disease pharmacokinetics.

Chemokine receptor 9 (CCR9), a cell surface chemokine receptor which belongs to the G protein-coupled receptor, 7-trans-membrane superfamily, is expressed on lymphocytes in the circulation and is the key chemokine receptor that enables these cells to target the intestine. It has been proposed that CCR9 antagonism represents a means to prevent the aberrant immune response of inflammatory bowel disease in a localized and disease specific manner and one which is accessible to small mol. approaches. One possible reason why clin. studies with vercirnon, a prototype CCR9 antagonist, were not successful may be due to a relatively poor pharmacokinetic (PK) profile for the mol. We wish to describe work aimed at producing new, orally active CCR9 antagonists based on the 1,3-dioxoisoindoline skeleton. This study led to a number of compounds that were potent in the nanomolar range and which, on optimization, resulted in several possible preclin. development candidates with excellent PK properties.

Journal of Medicinal Chemistry published new progress about Anti-inflammatory agents. 56622-54-9 belongs to class pyridine-derivatives, and the molecular formula is C7H10N2, Quality Control of 56622-54-9.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem