Month: November 2022

Valo, Erkka published the artcileEffect of serum sample storage temperature on metabolomic and proteomic biomarkers, Product Details of C5H11NO2S, the publication is Scientific Reports (2022), 12(1), 4571, database is CAplus and MEDLINE.

Prospective biomarker studies can be used to identify biomarkers predictive of disease onset. However, if serum biomarkers are measured years after their collection, the storage conditions might affect analyte concentrations Few data exists concerning which metabolites and proteins are affected by storage at – 20¡ãC vs – 80¡ãC. Our objectives were to document analytes affected by storage of serum samples at – 20¡ãC vs – 80¡ãC, and to identify those indicative of the storage temperature We utilized liquid chromatog. tandem mass spectrometry and Luminex to quantify 300 analytes from serum samples of 16 Finnish individuals with type 1 diabetes, with split-aliquot samples stored at – 80¡ãC and – 20¡ãC for a median of 4.2 years. Results were validated in 315 Finnish and 916 Scottish individuals with type 1 diabetes, stored at – 20¡ãC and at – 80¡ãC, resp. After quality control, we analyzed 193 metabolites and proteins of which 120 were apparently unaffected and 15 clearly susceptible to storage at – 20¡ãC vs – 80¡ãC. Further, we identified serum glutamate/glutamine ratio greater than 0.20 as a biomarker of storage at – 20¡ãC vs – 80¡ãC. The results provide a catalog of analytes unaffected and affected by storage at – 20¡ãC vs – 80¡ãC and biomarkers indicative of sub-optimal storage.

Scientific Reports published new progress about 63-68-3. 63-68-3 belongs to catalysis-chemistry, auxiliary class Natural product, name is (S)-2-Amino-4-(methylthio)butanoic acid, and the molecular formula is C10H2F12NiO4, Product Details of C5H11NO2S.

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

Armstrong, Susan K. published the artcileOn the stereoselectivity of nitrone addition to ¦Á-diphenylphosphinoylalkenes, Name: Allyldiphenylphosphine oxide, the publication is Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) (1994), 2825-31, database is CAplus.

The title reaction was studied for both achiral and ¦Á-chiral alkenes and for cyclic and acyclic nitrones, e.g., I. In each case, addition to allyldiphenylphosphine oxide 1 gave a single isoxazolidine product, e.g., II. The configurations of these isoxazolidines were studied by NMR methods, and are consistent with reaction via exo transition states. Nitrone additions to ¦Á-chiral ¦Á-diphenylphosphinoyl alkenes gave two diastereoisomeric products in all cases studied. The configurations of these isoxazolidines were assigned by analogy with the achiral cases, and also by analogy with the addition of nitrile oxides to the same alkenes. This conversion also demonstrated the potential of this method for the synthesis of 2-(alk-2′-enyl)piperidines having defined double-bond geometry.

Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) 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, Name: Allyldiphenylphosphine oxide.

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

Armstrong, Susan K. published the artcileA new method for stereoselective homoallylic amine synthesis, Recommanded Product: Allyldiphenylphosphine oxide, the publication is Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) (1993), 1433-47, database is CAplus.

Nitrile oxide cycloadditions to readily available allylic diphenylphosphine oxides [Ph₂P(O)CHR¹CH:CH₂; R¹ = H, Me, Et, Pr, isobutyl] proceeded regioselectively and stereoselectively to give 5-(1′-diphenylphosphinoyalkyl)isoxazolines [I and II; R¹ as above, R² = Et, Pr, hexyl, Ph, Me, CO₂Et,(CH₂)_nCO₂Me, n = 2,3]. These heterocycles were reduced to ¦Ä-amino-¦Â-hydroxyalkyldiphenylphosphine oxides (III and IV; R¹, R² as above) using a combination of sodium borohydride and nickel(II) chloride. Stereospecific elimination of diphenylphosphinic acid from the reduction products using sodium hydride in N,N-dimethylformamide gave homoallylic primary amines (V and VI; R¹, R² as above) of defined stereochem.

Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) 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, Recommanded Product: Allyldiphenylphosphine oxide.

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

Dallemer, F. published the artcileSynthesis of tertiary phosphine oxides mediated by SmCp₂ or SmI₂, Formula: C15H15OP, the publication is Applied Organometallic Chemistry (1995), 9(5 & 6), 431-5, database is CAplus.

Tertiary phosphine oxides are prepared under mild conditions by sequential addition of diphenylphosphinoyl chloride to divalent samarium compounds (SmCp₂ and SmI₂) followed by reaction with various electrophiles such as organic halides, tosylates, epoxides or ¦Á,¦Â-unsaturated ketones. Biscyclopentadienylsamarium (SmCp₂) gives better yields than SmI₂. Similar reactions, using phenylphosphonoyl dichloride, SmI₂ and subsequent addition of two equivalent of activated halides, yield the corresponding tertiary phosphine oxides.

Applied Organometallic Chemistry 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, Formula: C15H15OP.

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

Liang, Steven H. published the artcileRapid microfluidic flow hydrogenation for reduction or deprotection of ¹⁸F-labeled compounds, Application of Tetraethylammonium hydrogencarbonate, the publication is Chemical Communications (Cambridge, United Kingdom) (2013), 49(78), 8755-8757, database is CAplus and MEDLINE.

We have combined the benefits of both microfluidics and flow hydrogenation to provide facile access to previously underutilized reduction and protecting group chemistries for PET imaging applications. The rapid removal of an O-benzyl protecting group to prepare 2-[¹⁸F]fluoroquinolin-8-ol and the reduction of a nitro group in the synthesis of 4-[¹⁸F]fluoroaniline were achieved within 3 min.

Chemical Communications (Cambridge, United Kingdom) 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, Application of Tetraethylammonium hydrogencarbonate.

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

Torres, Alejandro published the artcileElectrocatalytic Behavior of Tetrathiafulvalene (TTF) and Extended Tetrathiafulvalene (exTTF) [FeFe] Hydrogenase Mimics, Product Details of C24H12, the publication is ACS Organic & Inorganic Au (2022), 2(1), 23-33, database is CAplus.

TTF- and exTTF-containing [(¦Ì-S₂)Fe₂(CO)₆] complexes have been prepared by the photochem. reaction of TTF or exTTF and [(¦Ì-S₂)Fe₂(CO)₆]. These complexes are able to interact with PAHs. In the absence of air and in acid media an electrocatalytic dihydrogen evolution reaction (HER) occurs, similarly to analogous [(¦Ì-S₂)Fe₂(CO)₆] complexes. However, in the presence of air, the TTF and exTTF organic moieties strongly influence the electrochem. of these systems. The reported data may be valuable in the design of [FeFe] hydrogenase mimics able to combine the HER properties of the [FeFe] cores with the unique TTF properties.

ACS Organic & Inorganic Au published new progress about 191-07-1. 191-07-1 belongs to catalysis-chemistry, auxiliary class Electronic Materials, name is Coronene, and the molecular formula is C18H34N4O5S, Product Details of C24H12.

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

Knott, Katrina K. published the artcileMercury, selenium, and fatty acids in the axial muscle of largemouth bass: evaluating the influence of seasonal and sexual changes in fish condition and reproductive status, Formula: C22H32O2, the publication is Ecotoxicology (2022), 31(5), 761-781, database is CAplus and MEDLINE.

Largemouth bass (LMB, 265-475 mm) were collected to document whether changes in fish condition and reproductive status influenced the concentration of total mercury (Hg) and selenium (Se) in axial muscle by season and sex. The fatty acid (FA) composition of fish was also examined to describe seasonal and sexual differences and identify whether arachidonic acid (ARA) could be used as a biomarker of Hg toxicity. There was a trend for females to have lower (p < 0.062) Se concentrations than males. The concentration of Se for females during spring (mean ¡À SD, 686 ¡À 51 ng/g dw) was 15% lower than males (806 ¡À 67 ng/g dw). Lower Se concentrations in females than males continued through summer and fall. Concentration of Hg for females during spring (152 ¡À 39 ng/g ww) was also 59% lower than males (373 ¡À 303 ng/g ww), but the difference was not significant (p > 0.2). The percent of lipids was greatest in fall and winter (3%) and comprised primarily of omega-3 fatty acids (35 g/100 g lipid). Fish condition as measured by percent lipids and relative weight was neg. (p < 0.02) related to Hg concentration for females and males. Lipid content for both sexes was also pos. (p < 0.05) related to the Se:Hg ratio. Relative weight was pos. related to the Se:Hg ratio for females during all seasons (p = 0.014), but only during spring and summer for males (p < 0.007). A low Se:Hg value was associated with an elevation in ARA for both sexes and a reduced hepatosomatic index in males. Data suggested that females transferred muscle stores of Se and Hg to developing oocytes during spring. This study generates hypotheses regarding the physiol. drivers of seasonal and sexual variability in Hg, Se, and FA in LMB that may be applicable to other species and have implications for fisheries health and management.

Ecotoxicology 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 C22H32O2, Formula: C22H32O2.

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

Mahanthappa, Mahesh K. published the artcileSynthesis, Structure, and Ethylene/¦Á-Olefin Polymerization Behavior of (Cyclopentadienyl)(nitroxide)titanium Complexes, Product Details of C14H23N, the publication is Organometallics (2004), 23(4), 836-845, database is CAplus.

Mono-Cp titanium coordination compounds bearing monoanionic ligands derived from stable nitroxyl radicals have been synthesized by two methods: (i) trapping of CpTi(III) species with the stable nitroxyl radical TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl) to provide Cp’TiCl₂(TEMPO) (Cp’ = Cp (1) and Cp^* (2)) and (ii) salt metathesis of Ti(IV) halides with a nitroxide anion generated by the in situ methylation of tert-butyl-¦Á-phenylnitrone. Alkylation of these complexes with MeLi or MeMgBr furnishes Cp^*TiMe₂(TEMPO) (3) and Cp’TiMe₂(ON(^tBu)(CHMePh)) (Cp’ = Cp (4) and Cp^* (5)). The mol. structure of 2 has been determined by x-ray crystallog. to reveal a monoanionic ¦Ç¹-TEMPO ligated to titanium. Complexes 3 and 4 activated with ^iprAFPB (2,6,-diisopropyl-N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate) efficiently copolymerize ethylene and 1-hexene to provide copolymers having higher 1-hexene contents and higher productivities than the related Cp^*Ti(CH₂Ph)₃ under identical conditions. Comparison of structural and electronic features as well as the ethylene/1-hexene copolymerization behavior of 3 and 4 with the constrained geometry catalyst [MeSi₂(¦Ç⁵-Me₄Cp)(¦Ç¹-N-tBu)]TiMe₂ provides insights into factors governing high comonomer incorporation by mono-Cp titanium complexes.

Organometallics published new progress about 2909-77-5. 2909-77-5 belongs to catalysis-chemistry, auxiliary class Amine,Benzene, name is 2,6-Diisopropyl-N,N-dimethylaniline, and the molecular formula is C14H23N, Product Details of C14H23N.

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

Gail, R. published the artcileA one step preparation of the n.c.a. fluorine-18 labeled synthons: 4-fluorobromobenzene and 4-fluoroiodobenzene, Synthetic Route of 17351-62-1, the publication is Applied Radiation and Isotopes (1994), 45(1), 105-11, database is CAplus.

4-¹⁸FC₆H₄X (X = Br, iodo) are interesting precursors for organometallic nucleophilic reagents. A 1-step preparation of these synthons was achieved by no-carrier-added (n.c.a.) nucleophilic exchange on the corresponding 4-bromo- and 4-iodophenyltrimethylammonium salts. The leaving ability of the trimethylammonium group increases strongly with decreasing basicity of the counteranion in the sequence: tosylate < Me sulfate < iodide < perchlorate (no data) < triflate. Systematic optimization leads to radiochem. yields of 50 ¡À 5% and 80 ¡À 5% within 5 min for the bromo and iodo derivs, resp., in AcNMe₂ as the solvent.

Applied Radiation and Isotopes published new progress about 17351-62-1. 17351-62-1 belongs to catalysis-chemistry, auxiliary class Salt,Amine, name is Tetrabutylammonium hydrogencarbonate, and the molecular formula is C17H37NO3, Synthetic Route of 17351-62-1.

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

Takacs, James M. published the artcileCatalytic Palladium-Mediated Bisdiene Carbocyclizations: Bisdiene to Ene diene Cycloisomerizations, Synthetic Route of 4141-48-4, the publication is Journal of the American Chemical Society (1997), 119(25), 5804-5817, database is CAplus.

The palladium-catalyzed cycloisomerization of acyclic bisdienes to cyclized ene dienes defines a novel strategy for the stereoselective cyclization of certain unsym. bisdiene substrates to form functionalized five- and six-membered rings. The full details of our investigation into this novel cycloisomerization, including our observations on substrate requirements, stereoselectivity, the influence of the catalyst precursor, and some mechanistic insights drawn from deuterium labeling studies, are discussed.

Journal of the American Chemical Society 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 C8H7ClO3, Synthetic Route of 4141-48-4.

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