Day: November 18, 2022

Wong, Siu Wai published the artcileDevelopment of [18F]MIPS15692, a radiotracer with in vitro proof-of-concept for the imaging of MER tyrosine kinase (MERTK) in neuroinflammatory disease, HPLC of Formula: 73874-95-0, the main research area is neuroinflammatory disease MER tyrosine kinase 18F MIPS15692 radiotracer; Autoradiography; CNS radiotracer; MER tyrosine Kinase; Multiple sclerosis; Positron emission tomography; X-ray crystallography.

MER tyrosine kinase (MERTK) upregulation is associated with M2 polarization of microglia, which plays a vital role in neuroregeneration following damage induced by neuroinflammatory diseases such as multiple sclerosis (MS). Therefore, a radiotracer specific for MERTK could be of great utility in the clin. management of MS, for the detection and differentiation of neuroregenerative and neurodegenerative processes. This study aimed to develop an [18F] ligand with high affinity and selectivity for MERTK as a potential positron emission tomog. (PET) radiotracer. MIPS15691 and MIPS15692 were synthesized and kinase assays were utilized to determine potency and selectivity for MERTK. Both compounds were shown to be potent against MERTK, with resp. IC50 values of 4.6 nM and 4.0 nM, and were also MERTK-selective. Plasma and brain pharmacokinetics were measured in mice and led to selection of MIPS15692 over MIPS15691. X-ray crystallog. was used to visualize how MIPS15692 is recognized by the enzyme. [18F]MIPS15692 was synthesized using an automated iPHASE FlexLab module, with a molar activity (Am) of 49 ± 26 GBq/μmol. The radiochem. purity of [18F]MIPS15692 was >99% and the decay-corrected radiochem. yields (RCYs) were determined as 2.45 ± 0.85%. Brain MERTK protein d. was measured by a saturation binding assay in the brain slices of a cuprizone mouse model of MS. High levels of specific binding of [18F]MIPS15692 to MERTK were found, especially in the corpus callosum/hippocampus (CC/HC). The in vivo PET imaging study of [18F]MIPS15692 suggested that its neuroPK is sub-optimal for clin. use. Current efforts are underway to optimize the neuroPK of our next generation PET radiotracers for maximal in vivo utility.

European Journal of Medicinal Chemistry published new progress about Blood plasma. 73874-95-0 belongs to class piperidines, name is tert-Butyl piperidin-4-ylcarbamate, and the molecular formula is C10H20N2O2, HPLC of Formula: 73874-95-0.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Nakatani, Hisayuki published the artcileNovel Recycling System of Polystyrene Water Debris with Polymer Photocatalyst and Thermal Treatment, COA of Formula: C28H52N2O4, the main research area is polystyrene hindered amine light stabilizer polymer photocatalyst thermal treatment.

A poly(styrene-block-acrylic acid) containing TiO2 gel (PS-b-PAA/TiO2) polymer photocatalyst had the same d. as PS and could provoke photocatalytic activity to PS particles in water. It showed photocatalytic activity to a PS containing a N-H type hindered amine light stabilizer (PS/LA-77) in water under the UV irradiation The mol. weight decrease was ca. 10%, showing that a weaker light source and different kind of hindered amine light stabilizer (HALS) should be employed. The phthalocyanine modified photocatalyst had the activity under visible light irradiation In addition, a N-OR type HALS (LA-81) loading worked as radical scavenger, showing that the PS autoxidation was certainly controlled. After the 144 h irradiation, the mol. weight was drastically decreased with the increases of heating temperature and time. When the heat treatment was performed by the enclosed sample with the aluminum foil, the mol. weight change behavior was considerably different between the PS and PS/LA-81. The difference was due to the chain scission mechanism. The intra-alkyl radical production in PS chain allowed controlling mol. weight by the heat treatment.

Journal of Polymers and the Environment published new progress about Autoxidation. 52829-07-9 belongs to class piperidines, name is Bis(2,2,6,6-tetramethylpiperidin-4-yl) decanedioate, and the molecular formula is C28H52N2O4, COA of Formula: C28H52N2O4.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Gajdosova, Veronika published the artcilePro-oxidant activity of biocompatible catechin stabilizer during photooxidation of polyolefins, HPLC of Formula: 52829-07-9, the main research area is oxidative biocompatible catechin stabilizer photooxidation polyolefin.

Polymer plaques made of high-d. polyethylene (HDPE) or cycloolefin copolymer (COC) were stabilized with natural phenolic stabilizer (+)-catechin (CAT) and aged using accelerated weathering technique (WOM; accelerated photooxidation). The efficiency of the phenolic stabilizer was compared with a well-established hindered amine stabilizer (HAS) Tinuvin770 (Tin770). In pursuit of the stabilization and identification of short-living radicals generated in the process of photooxidation of the polymers, a spin trapping agent 2,4,6-tri-tert-butylnitrosobenzene (TTBNB) was added to selected samples. Profiles of oxidation products and crystallinity inside the HDPE plaques were determined by IR microspectroscopy, oxidation products in COC copolymers were identified using ATR spectroscopy, concentration profiles of radicals generated inside polymer plaques during WOM exposure were determined by ESRI, the changes of local mech. properties at the surface of polymer plaques were characterized using microindentation hardness testing (MHI), and the surface morphol. changes were studied by light and/or SEM. All methods are in accordance with the conclusion that the natural phenolic stabilizer CAT exhibited pro-oxidant activity during accelerated photooxidation of both polymers, i.e. higher concentration of oxidation products, bigger changes of local mech. properties and/or more microcracks on the exposed surfaces in comparison with non-stabilized systems and systems stabilized with Tin770.

Polymer Degradation and Stability published new progress about Antioxidants. 52829-07-9 belongs to class piperidines, name is Bis(2,2,6,6-tetramethylpiperidin-4-yl) decanedioate, and the molecular formula is C28H52N2O4, HPLC of Formula: 52829-07-9.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Twigg, Christopher published the artcilePeroxide-initiated chemical modification of polyolefins: In search of a latent antioxidant, Formula: C28H52N2O4, the main research area is peroxide initiated polyolefin antioxidant.

The ability of piperidine-based compounds to confer oxidative stability to polyolefin thermosets without compromising the yields of peroxide-initiated crosslinking and monomer grafting is demonstrated. Unlike phenolic, nitroxyl and phosphite antioxidants that lower the concentration of macroradical intermediates that support polyolefin modifications, additives based upon 2,2,6,6-tetramethylpiperidine (TEMPH) are shown to have little to no effect on the extent of LLDPE crosslinking or the conversion of vinyltriethoxysilane (VTEOS) to grafted hydrocarbon adducts. Notwithstanding this lack of interference in radical-mediated polymer modification, this class of hindered light stabilizer (HAS) compounds are shown to limit the extent of radical oxidation of linear low-d. polyethylene (LLDPE) in an accelerated aging test. The origins of this paradox are discussed in terms of the current state of knowledge regarding HAS activation. The latent antioxidant concept is extended to an alternate approach, wherein 4-acryloyloxy-2,2,6,6-tetramethylpiperidine-N-oxyl (AOTEMPO) is used as an alkyl radical scavenger bearing an oligomerizable functional group. When added at a fraction of the peroxide loading used to produce an LLDPE thermoset, ATEMPO is shown to provide a predictable induction delay without impacting ultimate crosslink d., and produces polymer-bound alkoxyamine functionality that stabilizes the product against oxidation

Polymer published new progress about Antioxidants. 52829-07-9 belongs to class piperidines, name is Bis(2,2,6,6-tetramethylpiperidin-4-yl) decanedioate, and the molecular formula is C28H52N2O4, Formula: C28H52N2O4.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Kot, David published the artcilePorous graphite as stationary phase for the chromatographic separation of polymer additives – determination of adsorption capability by Raman spectroscopy and physisorption, Related Products of piperidines, the main research area is porous graphite stationary phase chromatog separation polymer additive antioxidant; adsorption capability Raman spectroscopy physisorption polyolefin light stabilizer; Adsorption potential distributions; Brunauer emmett teller (BET) method; HPLC of polymer additives; Polyolefins; Porous graphitic carbon; Raman spectroscopy.

Additives are added to polymers in small concentration to achieve desired application properties widely used to tailor the properties. The rapid diversification of their mol. structures, with often only minute differences, necessitates the development of adequate chromatog. techniques. While modified silica so far is the workhorse as stationary phase we have probed the potential of porous graphitic carbon (HypercarbTM) for this purpose. The results show that the multitude of physicochem. interactions between analyte mols. and the graphitic surface enables separations of polyolefin stabilizers with unprecedented selectivity. To support the chromatog. results the adsorption capability of HypercarbTM for selected antioxidants and UV absorbers was determined by Raman spectroscopy and argon physisorption measurements. The shift of the Graphite-band in the Raman spectra of HypercarbTM upon infusion with additives correlates with the changes in the Adsorption Potential Distributions. The results of argon physisorption measurements go hand in hand with the chronol. of desorption of the additives in liquid chromatog. experiments The elution sequence can be explained by van der Waals or London forces, π-π-interactions and electron lone pair donor-acceptor interactions between the graphite surface and analyte functional groups.

Journal of Chromatography A published new progress about Antioxidants. 52829-07-9 belongs to class piperidines, name is Bis(2,2,6,6-tetramethylpiperidin-4-yl) decanedioate, and the molecular formula is C28H52N2O4, Related Products of piperidines.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Zhang, Xi published the artcileDielectric Properties of Biaxially Oriented Polypropylene Nanocomposites Prepared Based on Reactor Granule Technology, COA of Formula: C28H52N2O4, the main research area is dielec biaxially oriented polypropylene nanocomposite reactor granule technol.

The addition of inorganic nanoparticles is one of the most widely studied strategies to improve dielec. properties of thin film capacitors, but its application to biaxially oriented polypropylene (BOPP) has rarely been reported due to the difficulty of stretching without break. Here, we have investigated dielec. properties of BOPP/TiO2 nanocomposites prepared by a reactor granule technol., in which precursors impregnated in the pores of PP reactor granule are converted into highly dispersed oxide nanoparticles during melt mixing. The permittivity of the nanocomposites was greatly enhanced beyond classical mixing rules by the addition of a small amount of TiO2 nanoparticles (1-5 wt %), and the enhancement was very sensitive to the stretching ratio. A critical role of the interphase region was suggested. The AC breakdown voltage (BDV) of the BOPP/TiO2 nanocomposites decreased sharply with respect to the amount of TiO2 added. The detailed anal. suggested the roughening of the film surface around the nanoparticles due to stretching as the main cause of the BDV reduction

ACS Applied Electronic Materials published new progress about Antioxidants. 52829-07-9 belongs to class piperidines, name is Bis(2,2,6,6-tetramethylpiperidin-4-yl) decanedioate, and the molecular formula is C28H52N2O4, COA of Formula: C28H52N2O4.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Pillay, M. Krishna published the artcileConformational analysis of heterocyclic systems: part-III conformational analysis of substituted N-acetypiperidin-4-ones, Computed Properties of 5773-58-0, the main research area is acetypiperidinone conformational analysis NMR.

The conformations of various substituted N-acetylpiperidin-4-ones have been analyzed by IR, 1H NMR and 13C NMR data. On the basis of these results, acetyl group adopting a coplanar orientation with the dynamically averaged plane of the ring is proposed. The energy barrier ΔG# for the rotation of the acetyl group has been evaluated.

Indian Journal of Heterocyclic Chemistry published new progress about Acetyl group. 5773-58-0 belongs to class piperidines, name is 3-Methylpiperidin-4-one, and the molecular formula is C6H11NO, Computed Properties of 5773-58-0.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Chang, Tianying published the artcileTerahertz dielectric spectroscopic analysis of polypropylene aging caused by exposure to ultraviolet radiation, Recommanded Product: Bis(2,2,6,6-tetramethylpiperidin-4-yl) decanedioate, the main research area is polypropylene aging UV radiation exposure terahertz dielec spectroscopic analysis; THz dielectric spectroscopy; polypropylene; ultraviolet aging.

Terahertz dielec. spectroscopy is shown to be an effective tool for bench-marking UV aging of polypropylene. In this, thin-film polypropylene samples exposed to standard artificial UV radiation in accelerated aging from 1 day to 30 days are closely monitored by a terahertz time-domain spectroscopy system and analyzed using an effective data processing method. It is found that the terahertz absorption of the polypropylene samples is generally weak and the terahertz dielec. constant varies slightly though discernibly during the aging process, with the refractive index decreasing slightly with increasing length of UV exposure. Nonetheless, the rate of variation of the polypropylene refractive index with increasing terahertz frequency exhibits a drastic inflection around the 15-days aging point and the rate changes suddenly from pos. value to neg. value. Based on this prominent and consistent THz dielec. spectroscopic feature of the aging process, an efficient judging criterion is established to distinguish the early-term, mid-term, and late-term phases as well as the degree of polypropylene UV aging, corresponding to the fundamental transformation of the polymer material from a nonpolar to a polar substance at a critical level of oxidation induced by UV radiation.

Polymers (Basel, Switzerland) published new progress about Absorptivity. 52829-07-9 belongs to class piperidines, name is Bis(2,2,6,6-tetramethylpiperidin-4-yl) decanedioate, and the molecular formula is C28H52N2O4, Recommanded Product: Bis(2,2,6,6-tetramethylpiperidin-4-yl) decanedioate.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Serrano, Catherine M. published the artcileUnifying the Aminohexopyranose- and Peptidyl-Nucleoside Antibiotics: Implications for Antibiotic Design, Safety of tert-Butyl piperidin-4-ylcarbamate, the main research area is tuberculosis antiretroviral amicetin prokaryotic translation inhibitor; amicetin; antibiotic; blasticdin S; ribosome; translation inhibitor.

In search of new anti-tuberculars compatible with anti-retroviral therapy we re-identified amicetin as a lead compound Amicetin’s binding to the 70S ribosomal subunit of Thermus thermophilus (Tth) has been unambiguously determined by crystallog. and reveals it to occupy the peptidyl transferase center P-site of the ribosome. The amicetin binding site overlaps significantly with that of the well-known protein synthesis inhibitor balsticidin S. Amicetin, however, is the first compound structurally characterized to bind to the P-site with demonstrated selectivity for the inhibition of prokaryotic translation. The natural product-ribosome structure enabled the synthesis of simplified analogs that retained both potency and selectivity for the inhibition of prokaryotic translation.

Angewandte Chemie, International Edition published new progress about 70S ribosome. 73874-95-0 belongs to class piperidines, name is tert-Butyl piperidin-4-ylcarbamate, and the molecular formula is C10H20N2O2, Safety of tert-Butyl piperidin-4-ylcarbamate.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem

Valenta, Vladimir published the artcilePotential neuroleptics of the orthopramide series; synthesis of heterocyclic 5-amino-2-methoxybenzamides and of some related compounds, Name: 1-Benzylpiperidin-4-amine dihydrochloride, the main research area is neuroleptic aminomethoxybenzamide heterocyclic preparation.

Condensation of 2,5-MeO(O2N)C6H3COCl with heterocyclic amines and hydrazines gave the title derivatives I (R = NO2, n = 0, 1) and II (R = NO2; Z = NH, X = CH, N; Z = bond, X = N). Reduction of I and II (R = NO2) with Raney Ni gave amino derivatives I and II (R = NH2). I (R = NHMe, n = 1) and II (R = NHMe, Z = NH, X = CH) were prepared via tosyl derivatives All prepared compounds I and II were tested as potential neuroleptics. Only compounds II (Z = NH, X = CH) show mild activity.

Collection of Czechoslovak Chemical Communications published new progress about Tranquilizers. 1205-72-7 belongs to class piperidines, name is 1-Benzylpiperidin-4-amine dihydrochloride, and the molecular formula is C12H20Cl2N2, Name: 1-Benzylpiperidin-4-amine dihydrochloride.

Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem