Month: November 2022

Sifri, Renee J. published the artcilePhotocontrolled cationic degenerate chain transfer polymerizations via thioacetal initiators, Category: catalysis-chemistry, the publication is Polymer Chemistry (2020), 11(40), 6499-6504, database is CAplus.

Recent developments in photocontrolled polymerizations have facilitated the development of previously inaccessible materials. While photocontrolled radical polymerizations have been extensively studied, related processes involving cationic polymerizations are underexplored and limited to RAFT processes. In this study, we disclose a visible light, temporally controlled cationic polymerization of vinyl ethers utilizing thioacetals and a photoredox catalyst. We demonstrate a broad scope of thioacetal initiators that achieve a well-controlled polymerization by recapping propagating chains via photocatalyst turnover in combination with a degenerate chain transfer process through sulfonium intermediates. Furthermore, we show that a photocatalyst with a more reducing ground state reduction potential allows for enhanced control and excellent temporal regulation of polymerization

Polymer Chemistry published new progress about 22693-41-0. 22693-41-0 belongs to catalysis-chemistry, auxiliary class Other Functionalization Reagent, name is 2,4,6-Triisopropylbenzenethiol, and the molecular formula is C16H20N2, Category: catalysis-chemistry.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Patil, Nandkumar M. published the artcileNovel cuprous iodide-tributylphosphine catalyst system for amination of aryl chlorides, Product Details of C12H9N3O4, the publication is Chemical Communications (Cambridge, United Kingdom) (2003), 2460-2461, database is CAplus and MEDLINE.

A simple and efficient methodol. for the synthesis of triarylamines from aryl chlorides in a single step was demonstrated using a novel cuprous iodide-tributylphosphine catalyst system with high activity and selectivity (80-87% yield).

Chemical Communications (Cambridge, United Kingdom) published new progress about 1821-27-8. 1821-27-8 belongs to catalysis-chemistry, auxiliary class Nitro Compound,Amine,Benzene, name is Bis(4-nitrophenyl)amine, and the molecular formula is C12H9N3O4, Product Details of C12H9N3O4.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Mielby, Jerrik published the artcileEpoxidation of Alkenes with Aqueous Hydrogen Peroxide and Quaternary Ammonium Bicarbonate Catalysts, Quality Control of 17351-61-0, the publication is Catalysis Letters (2013), 143(11), 1162-1165, database is CAplus.

A range of solid and liquid catalysts containing bicarbonate anions were synthesized and tested for the epoxidation of alkenes with aqueous hydrogen peroxide. The combination of bicarbonate anions and quaternary ammonium cations opens up for new catalytic systems that can help to overcome challenges with catalyst separation and reuse.

Catalysis Letters published new progress about 17351-61-0. 17351-61-0 belongs to catalysis-chemistry, auxiliary class Phase Transfer Catalyst, name is Tetraethylammonium hydrogencarbonate, and the molecular formula is C9H21NO3, Quality Control of 17351-61-0.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Delventhal, Juergen published the artcileCoordination-polymeric metal complexes as stationary phases in gas chromatography, Product Details of C10H23N, the publication is Angewandte Chemie, International Edition in English (1972), 11(9), 830, database is CAplus.

Relative retention volumes of some Lewis bases (pyridine, amines, and thiophene) in gas chromatog. on Chromosorb containing p-phenylenebis[(p-methoxyphenyl)phosphinodithioate] complexes of Ni(II) or Co(II) were reported. The main advantage of the above column packings is their chem. and thermal stability.

Angewandte Chemie, International Edition in English published new progress about 28056-87-3. 28056-87-3 belongs to catalysis-chemistry, auxiliary class Amine,Aliphatic hydrocarbon chain, name is 2-Ethyl-N,N-dimethylhexan-1-amine, and the molecular formula is C10H23N, Product Details of C10H23N.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Rand, Matthew D. published the artcilePermeabilization of Drosophila embryos for introduction of small molecules, Product Details of C18H15N3O3, the publication is Insect Biochemistry and Molecular Biology (2010), 40(11), 792-804, database is CAplus and MEDLINE.

Pharmacol. manipulations in the Drosophila embryo have been hindered by the impermeability of the eggshell. The ultimate barrier to delivery of small mol. solutes to the embryo is the waxy layer that lies beneath the external chorion layers and encases the underlying vitelline membrane of the eggshell. Conventional protocols call for heptane or octane to permeabilize the dechorionated eggshell however, these solvents are toxic and can result in low viability. Furthermore, heptane and octane require transition of the embryo between aqueous and organic phase solvents making it challenging to avoid desiccation. Here we describe an embryo permeabilization solvent (EPS) composed of D-limonene and plant-derived surfactants that is water miscible and highly effective in rendering the dechorionated eggshell permeable. EPS permeabilization enables embryo uptake of several different dyes of various mol. mass up to 995 Da. We find that the embryo undergoes an age-dependent decrease in the ability to be permeabilized in the first six to eight hours after egg laying. This apparent developmental change in the vitelline membrane contributes to the heterogeneity in permeabilization seen even among closely staged embryos. However, using fluorescent properties of Rhodamine B dye and various conditions of EPS treatment we demonstrate the ability to obtain optimally permeabilized viable embryos. We also demonstrate the ability to assess teratogenic activity of several compounds applied to embryos in vitro, using both early and late developmental endpoints. Application of the method to transgenic strains carrying GFP-reporter genes results in a robust readout of pharmacol. alteration of embryogenesis. The straightforward and rapid nature of the manipulations needed to prepare batches of permeabilized embryos has the potential of establishing the Drosophila embryo as an alternative model in toxicol. and for small mol. screening in a high-throughput format.

Insect Biochemistry and Molecular Biology published new progress about 10510-54-0. 10510-54-0 belongs to catalysis-chemistry, auxiliary class Other Aromatic Heterocyclic,Salt,Amine,Inhibitor,Inhibitor, name is 5,9-Diaminobenzo[a]phenoxazin-7-ium acetate, and the molecular formula is C18H15N3O3, Product Details of C18H15N3O3.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Koronkiewicz, Miroslawa published the artcileProapoptotic effects of new pentabromobenzylisothiouronium salts in a human prostate adenocarcinoma cell line, Recommanded Product: 1,1-Dimethylthiourea, the publication is Acta Poloniae Pharmaceutica (2012), 69(6), 1325-1333, database is CAplus and MEDLINE.

Prostate cancer is the second most common cancer in elderly men worldwide and its incidence rate is rising continuously. Agents capable of inducing apoptosis in prostate cancer cells seem a promising approach to treat this malignancy. In this study we describe the synthesis of a number of novel N- and N,N’-substituted S-2,3,4,5,6-pentabrornobenzylisothiouronium bromides and their activity against the human prostate adenocarcinoma PC3 cell line. All the compounds produced changes in mitochondrial transmembrane potential and cell cycle progression, showed a cytostatic effect and induced apoptosis in the tested cancer line in a concentrationand time-dependent manner. The most effective compounds ZKK-3, ZKK-9 and ZKK-13 produced, at 20 ¦ÌM concentration, apoptosis in 42, 46, and 66% of the cells, resp., after 48 h incubation. Two selected S-2,3,4,5,6-pentabromobenzylisothiouronium bromides (ZKK-3, ZKK-9) showed also a synergic proapoptotic effect with the new casein kinase II inhibitor 2-(4-methylpiperazin-l-yl)-4,5,6,7-tetrabromo-1H-benzimidazole (TBIPIP) in the PC3 cell line.

Acta Poloniae Pharmaceutica published new progress about 6972-05-0. 6972-05-0 belongs to catalysis-chemistry, auxiliary class Thiourea,Amine,Aliphatic hydrocarbon chain,Amide, name is 1,1-Dimethylthiourea, and the molecular formula is C3H8N2S, Recommanded Product: 1,1-Dimethylthiourea.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Ozcan, Sevil published the artcileOxadiazole-isopropylamides as Potent and Noncovalent Proteasome Inhibitors, Recommanded Product: 2-(4-(tert-Butyl)phenoxy)acetic acid, the publication is Journal of Medicinal Chemistry (2013), 56(10), 3783-3805, database is CAplus and MEDLINE.

Screening of the 50 000 ChemBridge compound library led to the identification of the oxadiazole-isopropylamide I (PI-1833) which inhibited chymotrypsin-like (CT-L) activity (IC₅₀ = 0.60 ¦ÌM) with little effects on the other two major proteasome proteolytic activities, trypsin-like (T-L) and postglutamyl-peptide-hydrolysis-like (PGPH-L). LC-MS/MS and dialysis show that I is a noncovalent and rapidly reversible CT-L inhibitor. Focused library synthesis provided II (PI-1840) with CT-L activity (IC₅₀ = 27 nM). Detailed SAR studies indicate that the amide moiety and the two Ph rings are sensitive toward modifications. Hydrophobic residues, such as Pr or Bu in the para position (not ortho or meta) of the A-ring and a m-pyridyl group as B-ring, significantly improve activity. Compound II (IC₅₀ = 0.37 ¦ÌM) is more potent than I (IC₅₀ = 3.5 ¦ÌM) at inhibiting CT-L activity in intact MDA-MB-468 human breast cancer cells and inhibiting their survival. The activity of II warrants further preclin. investigation of this class as noncovalent proteasome inhibitors.

Journal of Medicinal Chemistry published new progress about 1798-04-5. 1798-04-5 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ether, name is 2-(4-(tert-Butyl)phenoxy)acetic acid, and the molecular formula is C12H16O3, Recommanded Product: 2-(4-(tert-Butyl)phenoxy)acetic acid.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Ozcan, Sevil published the artcileOxadiazole-isopropylamides as Potent and Noncovalent Proteasome Inhibitors, Synthetic Route of 163839-73-4, the publication is Journal of Medicinal Chemistry (2013), 56(10), 3783-3805, database is CAplus and MEDLINE.

Screening of the 50 000 ChemBridge compound library led to the identification of the oxadiazole-isopropylamide I (PI-1833) which inhibited chymotrypsin-like (CT-L) activity (IC₅₀ = 0.60 ¦ÌM) with little effects on the other two major proteasome proteolytic activities, trypsin-like (T-L) and postglutamyl-peptide-hydrolysis-like (PGPH-L). LC-MS/MS and dialysis show that I is a noncovalent and rapidly reversible CT-L inhibitor. Focused library synthesis provided II (PI-1840) with CT-L activity (IC₅₀ = 27 nM). Detailed SAR studies indicate that the amide moiety and the two Ph rings are sensitive toward modifications. Hydrophobic residues, such as Pr or Bu in the para position (not ortho or meta) of the A-ring and a m-pyridyl group as B-ring, significantly improve activity. Compound II (IC₅₀ = 0.37 ¦ÌM) is more potent than I (IC₅₀ = 3.5 ¦ÌM) at inhibiting CT-L activity in intact MDA-MB-468 human breast cancer cells and inhibiting their survival. The activity of II warrants further preclin. investigation of this class as noncovalent proteasome inhibitors.

Journal of Medicinal Chemistry published new progress about 163839-73-4. 163839-73-4 belongs to catalysis-chemistry, auxiliary class Trifluoromethyl,Fluoride,Carboxylic acid,Benzene,Ether, name is 2-(4-(Trifluoromethyl)phenoxy)acetic acid, and the molecular formula is C9H7F3O3, Synthetic Route of 163839-73-4.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Kahraman, M. Vezir published the artcileFlame retardance of epoxy acrylate resin modified with phosphorus containing compounds, Quality Control of 4141-48-4, the publication is Progress in Organic Coatings (2004), 51(3), 213-219, database is CAplus.

In this work, UV-radiation curing of allyldiphenyl phosphine oxide (ADPPO) and 4,4′-bis(allyloxyphenyl) Ph phosphine oxide (DAPPO) monomers with epoxy acrylate resin in the presence of a photoinitiator was studied and their flame-retardant performance compared with pure epoxy acrylate film. The structures of allyl functional phosphorus compounds were characterized by FT-IR, ¹H NMR, ¹³C NMR and all spectra were consistent with the expected structures. The polymerization behavior of both allyl functional monomers was followed in detail by monitoring the disappearance of acrylate and allyl groups by real-time IR spectroscopy. The reactivity of DAPPO monomer is higher than ADPPO. In the case of ADPPO, chain transfer to monomer basically predominates. In each monomer, a tack free coating was obtained immediately upon irradiation The addition of DAPPO leads to an improvement of the thermal and flame-retardant properties of the polymeric films. Thermal gravimetric anal. of DAPPO containing polymeric films gave higher char yield compared with UV-cured pure epoxy acrylate resin.

Progress in Organic Coatings published new progress about 4141-48-4. 4141-48-4 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Allyldiphenylphosphine oxide, and the molecular formula is C15H15OP, Quality Control of 4141-48-4.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Shibata, Takeaki published the artcileAbnormal male reproduction and embryonic development induced by downregulation of a phospholipid fatty acid-introducing enzyme Lpgat1 in zebrafish, Safety of Docosahexaenoic Acid, the publication is Scientific Reports (2022), 12(1), 7312, database is CAplus and MEDLINE.

Phospholipids in the membrane consist of diverse pairs of fatty acids bound to a glycerol backbone. The biol. significance of the diversity, however, remains mostly unclear. Part of this diversity is due to lysophospholipid acyltransferases (LPLATs), which introduce a fatty acid into lysophospholipids. The human genome has 14 LPLATs and most of them are highly conserved in vertebrates. Here, we analyzed the function of one of these enzymes, lysophosphatidylglycerol acyltransferase 1 (Lpgat1), in zebrafish. We found that the reproduction of heterozygous (lpgat1+/-) male mutants was abnormal. Crosses between heterozygous males and wild-type females produced many eggs with no obvious cleavage, whereas eggs produced by crosses between heterozygous females and wild-type males cleaved normally. Consistent with this, spermatozoa from heterozygous males had reduced motility and abnormal morphol. We also found that the occurrence of lpgat1 homozygous (lpgat1-/-) mutants was far lower than expected. In addition, downregulation of lpgat1 by morpholino antisense oligonucleotides resulted in severe developmental defects. Lipidomic anal. revealed that selective phospholipid species with stearic acid and docosahexaenoic acid were reduced in homozygous larvae and spermatozoa from heterozygotes. These results suggest that the specific phospholipid mol. species produced by Lpgat1 have an essential role in sperm fertilization and in embryonic development.

Scientific Reports published new progress about 6217-54-5. 6217-54-5 belongs to catalysis-chemistry, auxiliary class Alkenyl,Carboxylic acid,Aliphatic hydrocarbon chain,Metabolic Enzyme,RAR/RXR,Natural product, name is Docosahexaenoic Acid, and the molecular formula is C25H34N4O2S, Safety of Docosahexaenoic Acid.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia