Catalysis-chemistry

Watanabe, Masashi published the artcileCoil Formation of a Silicone String Using UV-Ozone Treatment, Recommanded Product: 3-(Trimethoxysilyl)propan-1-amine, the publication is ACS Omega (2022), 7(13), 11363-11370, database is CAplus and MEDLINE.

Microcoils are used in various mech. devices. However, existing methods for producing microcoils from polymers often require expensive equipment. In this study, microcoils were prepared using a cost-effective and simple method. The material used was silicone, which is a biocompatible polymeric material. Silicone was solidified inside glass capillaries to form thin, straight strings with a diameter of 140¦Ìm. The string was then transformed to a coil shape by oxidation using UV-ozone treatment while it was prestretched and pretwisted. The resilience force from the prestretching and pretwisting forces caused the string to bend and twist, resp. As a result of the combination of these deformation modes, a coil was formed. As an application of the coils, an actuator was prepared, which repeatedly transforms between straight and coiled shapes. The actuation was caused by the swelling/deswelling of silicone with hexane. A large strain of 54% was obtained.

ACS Omega published new progress about 13822-56-5. 13822-56-5 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is 3-(Trimethoxysilyl)propan-1-amine, and the molecular formula is C4Br2N2O4S, Recommanded Product: 3-(Trimethoxysilyl)propan-1-amine.

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

Pietrasiak, Ewa published the artcileSynthesis and characterization of fluorinated hypervalent tellurium derivatives, Category: catalysis-chemistry, the publication is Organometallics (2017), 36(19), 3750-3757, database is CAplus.

Aryl telluroethers o-substituted with acetal, aldehyde, ketone, carboxylate or aldimine donor atom functions were prepared and examined for hypervalent Te-heteroatom binding by x-ray crystallog. and tellurium-125 NMR spectra. The synthesis of tellurium derivatives bearing fluorinated groups, similar in structure to their hypervalent iodine congeners, is reported. Thus, a series of CF₃, CF₂H, and C₆F₅ aryltellurium(II) species bearing various functional groups interacting with the Te atom was obtained. The installation of the various fluorinated groups relies on the use of the corresponding trimethylsilyl precursors. The hypervalent nature of the products is discussed on the basis of their NMR spectroscopic and X-ray crystallog. characterization.

Organometallics published new progress about 1206-46-8. 1206-46-8 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is Trimethyl(perfluorophenyl)silane, and the molecular formula is C9H9F5Si, Category: catalysis-chemistry.

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

Rol, Alvaro published the artcileStructure-based design of a Cortistatin analogue with immunomodulatory activity in models of inflammatory bowel disease, SDS of cas: 71989-31-6, the publication is Nature Communications (2021), 12(1), 1869, database is CAplus and MEDLINE.

Ulcerative colitis and Crohn¡äs disease are forms of inflammatory bowel disease whose incidence and prevalence are increasing worldwide. These diseases lead to chronic inflammation of the gastrointestinal tract as a result of an abnormal response of the immune system. Recent studies positioned Cortistatin, which shows low stability in plasma, as a candidate for IBD treatment. Here, using NMR structural information, we design five Cortistatin analogs adopting selected native Cortistatin conformations in solution One of them, A5, preserves the anti-inflammatory and immunomodulatory activities of Cortistatin in vitro and in mouse models of the disease. Addnl., A5 displays an increased half-life in serum and a unique receptor binding profile, thereby overcoming the limitations of the native Cortistatin as a therapeutic agent. This study provides an efficient approach to the rational design of Cortistatin analogs and opens up new possibilities for the treatment of patients that fail to respond to other therapies.

Nature Communications published new progress about 71989-31-6. 71989-31-6 belongs to catalysis-chemistry, auxiliary class Amino acide derivatives,pyrrolidine, name is Fmoc-Pro-OH, and the molecular formula is C20H19NO4, SDS of cas: 71989-31-6.

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

Dahn, Hans published the artcileNMR of terminal oxygen. Oxygen-17 NMR of the phosphorus-oxygen ‘double bond’: phosphine oxides, phosphinates, phosphonates, acylphosphonates and related compounds, COA of Formula: C18H23OP, the publication is Magnetic Resonance in Chemistry (1992), 30(11), 1089-96, database is CAplus.

The ¹⁷O NMR spectra of P-bound O atoms in secondary phosphine oxides (R₂HPO), alkyl phosphinates [RHP(O)OR’ and R₂P(O)OR’], dialkyl phosphonates [RP(O)(OR’)₂], dialkyl acylphosphonates [RCOP(O)(OR’)₂] and some related compounds were measured. The signals of terminal O appear at high field, only slightly downfield from those of bridge O. Compared with carbonyl O, terminal P-O shows lower sensitivity to structural variations, notably to geminal groups (with the exception of Cl and Br), and a very low sensitivity to arene ring substituents. The difference is discussed in terms of ¦Ð-bond character; the carbonyl O of RCOP(O)(OR’)₂ is sensitive to variations in structure.

Magnetic Resonance in Chemistry published new progress about 23897-16-7. 23897-16-7 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Dimesitylphosphine oxide, and the molecular formula is C18H23OP, COA of Formula: C18H23OP.

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

Dolui, Pritam published the artcileA Catalyst and Solvent Free Route for the Synthesis of N-Substituted Pyrrolidones from Levulinic Acid, Quality Control of 2051-95-8, the publication is Chemistry – A European Journal (2022), 28(43), e202200829, database is CAplus and MEDLINE.

An efficient, metal-free, catalyst-free and solvent-free methodol. for the reductive amination of levulinic acid with different anilines was developed using HBpin as the reducing reagent. This protocol offered an excellent method to avoid solvents and added catalysts on the synthesis of different kinds of N-substituted pyrrolidones under metal free conditions. It is also the first report for the synthesis of different pyrrolidones by solvent-free as well as catalyst-free methods. The proposed mechanism for the formation of pyrrolidone was supported by DFT calculations and control experiments

Chemistry – A European Journal published new progress about 2051-95-8. 2051-95-8 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ketone, name is 3-Benzoylpropionicacid, and the molecular formula is C10H10O3, Quality Control of 2051-95-8.

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

Eriksson, Ulrika published the artcileExamination of aryl hydrocarbon receptor (AhR), estrogenic and anti-androgenic activities, and levels of polyaromatic compounds (PACs) in tire granulates using in vitro bioassays and chemical analysis, Recommanded Product: Coronene, the publication is Chemosphere (2022), 134362, database is CAplus and MEDLINE.

Tire granulates recovered from end-of-life tires contain a complex mixture of chems., amongst them polyaromatic compounds (PACs), of which many are recognized to be toxic and persistent in the environment. Only a few of these PACs are regularly monitored. In this study a combined approach of chem. anal. and a battery of CALUX in vitro bioassays was used to determine PAC concentrations and estrogenic, (anti)-androgenic and aryl hydrocarbon receptor (AhR) activities in tire granulates. Tire granulates from a recycling company was analyzed for PAHs, alkyl-PAHs, oxy-PAHs and heterocyclic PACs (NSO-PACs), in total 85 PACs. The concentrations of PACs were between 42 and 144 mg/kg, with major contribution from PAHs (74-88%) followed by alkyl-PAHs (6.6-20%) and NSO-PACs (1.8-7.0%). The sum of eight priority PAHs were between 2.3 and 8.6 mg/kg, contributing with 4.7-8.2% of ¡ÆPACs. Bioassay anal. showed presence of AhR agonists, estrogen receptor (ER¦Á) agonists, and androgen receptor (AR) antagonists in the tire granulate samples. Only 0.8-2.4% of AhR-mediated activities could be explained by the chem. anal. Benzo[k+j]fluoranthenes, benzo[b]fluoranthene, indeno[1,2,3-cd]pyrene, 2-methylchrysene, and 3-methylchrysene were the major contributors to the AhR-mediated activities. The high contribution (98-99%) of unknown bioactive compounds to the bioassay effects in this study raises concerns and urges for further investigations of toxicants identification and source apportionment.

Chemosphere 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 C24H12, Recommanded Product: Coronene.

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

Fieser, Louis F. published the artcileVitamin K activity and structure, SDS of cas: 1949-41-3, the publication is Journal of Biological Chemistry (1941), 659-92, database is CAplus.

The vitamin K activity of various quinones (uniform testing technique was used) was re?xamd., these results superseding all previous data (C. A. 34, 1649.8, 3724.3, 7895.4-5, 6336.7). 2-Methyl-1,4-naphthoquinone (I) was 3.3 times as effective as synthetic K₁. The following group of 2,3-disubstituted 1,4-naphthoquinones had the min. EDs indicated: 2-methyl-3-phytyl, 2-methyl-3-farnesyl, 2-methyl-3-(¦Â,¦Ã-dihydrophytyl), 2-methyl-3-geranyl, 2-methyl-3-cinnamyl, 2-methyl-3-(¦Â,¦Ã,¦Ã,-trimethylallyl), 2,3-di-Me, 2-methyl-3-benzyl, 2-methyl-3-hydrocinnamyl: 1, 5, 8, 25, 25, 50, 50, 200 and 300 ¦Ã, resp. The dihydro K₁ with an activity of 8 was much more active than previous reports indicated (C. A. 34, 5437.7, 5493.4). Comparison of ¦Â-alkenyl derivatives shows that activity increases with length of chain to 20 C atoms, after which it is little affected by further increase in length. Of the monosubstituted 1,4-naphthoquinones, I, phytyl, farnesyl, ¦Â,¦Ã-dihydrophytyl, allyl, geranyl, Et and Pr were effective in doses of 0.3, 50, 500, 600, 800 and 1000 ¦Ã, resp., the last two being inactive. EDs for other 1,4-naphthoquinones were as follows: 2-ethyl-3-phytyl, 2,3-diallyl, and 2,7-di-Me, 1000 ¦Ã; 2,5-di-Me and 2,8-di-Me, 500 ¦Ã (slight); 2,6-dimethyl-3-phytyl, 2,6-di-Me, 6,7-di-Me, inactive at 1000. 1,1-Dimethyl-3-tert-butyl- and 2-(¦Ä-methyl-¦Ã-pentenyl)-1,4-dihydroanthraquinones were inactive at 1000 ¦Ã. Of the naphthoquinones containing O substituents, plumbagin and phthiocol had EDs at 400 and 500 ¦Ã, resp., while juglone, lawsone, lapachol, 2-¦Â-heptenyl-3-hydroxy-, 2-farnesyl-3-hydroxy-, and 2-methyl-3-(¦Ã-hydroxydihydrophytyl)-1,4-naphthoquinone, were inactive at 1000 ¦Ã, as was also hydroquinone diacetate; 2-methyl-3-carbethoxy-1,4-naphthohydroquinone, however, showed an ED of 25 ¦Ã, presumably because of conversion into 2-methylnaphthoquinone. Many of the oxides prepared from the quinones are active: vitamin K₁, I, 2,3-dimethyl-, 2-methyl-3-cinnamyl-, 2-phytyl-, 2-farnesyl- and 2,7-dimethyl-1,4-naphthoquinone oxides had EDs of 1.2, 5, 25, 150, 200, 1000 ¦Ã and inactive, resp. Vitamin K oxide is much less affected by light than the quinone form. Exposure to sunlight for 2 h. decreased the activity of the latter 90%, and of the former 30%. The vitamin may exist as the oxide in green plants. 2-Methyl-2-phytyl-2,3-dihydro-1,4-naphthoquinone and naphthotocopherol required 50 and 500 ¦Ã, resp., for an ED. The latter is of particular interest because it shows both vitamin E and vitamin K activity. Of the ethers and esters of 1,4-naphthohydroquinones (II), the Na salts of the 2-methyl-II diphosphoric acid ester, 2-methyl-II disulfuric acid ester, and 2,3-dimethyl-II disulfuric acid ester required for ED 0.5, 2 and 500 ¦Ã given orally (0.5 and 1-2 i.v.); vitamin K hydroquinone diphosphoric acid, 50 ¦Ã given orally, 10 i.v.; disulfuric acid ester, K salt, inactive at 500 ¦Ã. The following organic esters and ethers of 2-methyl-1,4-naphthohydroquinone had the ED indicated: di-Ac, di-Bz, dimesitoate, mono-Et ether, di-Me ether, dibenzyl ether, 1, 1, 300, 1, 5 and 7 ¦Ã, resp. 5,8-Dihydro- and ¦Â,¦Ã,5,6,7,8-hexahydrovitamin K₁, 5,8-dihydro-I, 5,8,9,10-tetrahydro-I and 5,6,7,8-tetrahydro-I had EDs of 4, 1000, 6, 8 and 500 ¦Ã, resp. The following naphthols and tetralones likewise showed high activity where biol. conversion to I could occur: I, 2-methyl-, 3-methyl-, and 4-methyl-1-naphthol, 1-methyl-, 3-methyl-2-naphthol, 1-naphthol, 2-methyl-, and 3-methyl-1-tetralone, 2-methyl-1-naphthylamine, 2-methylnaphthalene (II) and ¦Á-methyl-¦Ã-phenylbutyric acid (III) had the following EDs: 0.5, 1, 0.6, next 3 inactive at 1000, 1000, 0.6, 1, 5, 1000 and inactive at 1000 ¦Ã, resp. The organism does not appear able to oxidize II effectively or to cyclize III. The 2- and 3-methyltetralones are the stages furthest removed from the vitamin which are effectively converted to it by the organism.

Journal of Biological Chemistry published new progress about 1949-41-3. 1949-41-3 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene, name is 2-Methyl-4-phenylbutanoic acid, and the molecular formula is C11H14O2, SDS of cas: 1949-41-3.

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

Calimano, Elisa published the artcileSynthesis and Structure of PNP-Supported Iridium Silyl and Silylene Complexes: Catalytic Hydrosilation of Alkenes, Related Products of catalysis-chemistry, the publication is Journal of the American Chemical Society (2009), 131(31), 11161-11173, database is CAplus and MEDLINE.

Oxidative addition of bulky primary, secondary, and tertiary silanes to PNP (PNP = [N(2-PⁱPr₂-4-Me-C₆H₃)₂]^–) iridium complexes (PNP)IrH₂ and (PNP)Ir(COE) (11) afforded iridium silyl hydride complexes (PNP)Ir(H)(SiRR’R”) (3–8). Addition of 2 equivalent of PhSiH₃ or (3,5-Me₂C₆H₃)SiH₃ to (PNP)IrH₂ or 11 yielded disilyl complexes (PNP)Ir(SiH₂R)₂ (R = Ph (9), 3,5-Me₂C₆H₃ (10)). Hydride abstraction from (PNP)Ir(H)(SiH₂R) (R = Trip (5), Dmp (6)) by [Ph₃C][B(C₆F₅)₄] afforded iridium silylene complexes [(PNP)(H)Ir:SiR(H)][B(C₆F₅)₄] (R = Trip (12), Dmp (13)) exhibiting downfield ²⁹Si NMR resonances (234 ppm (12), 226 ppm (13)) and downfield ¹H NMR resonances for the Si-H group (10.76 ppm (12), 9.76 ppm (13)). Thermally stable disubstituted silylene complexes [(PNP)(H)Ir:SiPh₂][A] (A = ^–B(C₆F₅)₄ (14), ^–CB₁₁H₆Br₆ (16)) were isolated via hydride abstraction from (PNP)Ir(H)(SiHPh₂). The x-ray structure of 16 confirmed sp² hybridization at silicon and revealed a short Ir-Si bond of 2.210(2) ?. Catalytic hydrosilation of alkenes by hydrogen-substituted silylene complexes [(PNP)(H)Ir:SiMes(H)][B(C₆F₅)₄] (1) and 14 exhibited anti-Markovnikov regioselectivity with an array of alkene substrates. Addition of H₃SiMes to complex 1 afforded [(PNP)(SiH(Mes)(Hex))IrH(SiH₂Mes)][B(C₆F₅)₄] (19), featuring a ¦Â-agostic interaction demonstrated by a J_SiH of 102 Hz for the N-SiH hydrogen. Similarly, addition of H₂SiPh₂ to 16 afforded the structurally characterized Ir(V) disilyl complex [(PNP)(SiPh₂)Ir(SiPh₂H)(H)₂][CB₁₁H₆Br₆] (20). Complex 20 was catalytically active for the hydrosilation of alkenes, which is consistent with its intermediacy in the catalytic cycle.

Journal of the American Chemical Society published new progress about 457-68-1. 457-68-1 belongs to catalysis-chemistry, auxiliary class Fluoride,Benzene, name is Bis(4-fluorophenyl)methane, and the molecular formula is C13H10F2, Related Products of catalysis-chemistry.

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

Farooq, Omar published the artcileAlkali metal salts of perfluorinated complex anions. Effective reagents for nucleophilic fluorination, SDS of cas: 312-40-3, the publication is Journal of Organic Chemistry (1994), 59(8), 2122-4, database is CAplus.

Alkali metal salts of perfluorinated complex anions, e.g., NaPF₆, were used to effect halogen-exchange fluorination in organohalosilanes, e.g., Ph₃SiCl, both in the presence and absence of solvent. Using salts of perfluorinated nonnucleophilic anions in a high-boiling multifunctional etheral solvent, organofluorosilanes, e.g., Ph₃SiF, were conveniently prepared in high yields.

Journal of Organic Chemistry published new progress about 312-40-3. 312-40-3 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is Difluorodiphenylsilane, and the molecular formula is C12H10F2Si, SDS of cas: 312-40-3.

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

Tan, Sang Loon published the artcileA 1:1:1 co-crystal solvate comprising 2,2¡ä-dithiodibenzoic acid, 2-chlorobenzoic acid and N,N-dimethylformamide: crystal structure, Hirshfeld surface analysis and computational study, Name: 2,2′-Dithiodibenzoic acid, the publication is Acta Crystallographica, Section E: Crystallographic Communications (2019), 75(4), 475-481, database is CAplus and MEDLINE.

The asym. unit of the three-component title compound, 2,2¡ä-dithiodibenzoic acid-2-chlorobenzoic acid-N,N-dimethylformamide (1/1/1), C₁₄H₁₀O₄S₂¡¤C₇H₅ClO₂¡¤C₃H₇NO, contains a mol. each of 2,2¡ä-dithiodibenzoic acid (DTBA), 2-chlorobenzoic acid (2CBA) and DMF (DMF). The DTBA mol. is twisted and each carboxylic group is slightly twisted from the benzene ring to which it is connected. A small twist is evident in the mol. of 2CBA. In the crystal, the three mols. are connected by hydrogen bonds with the two carboxylic acid residues derived from DTBA and 2CBA forming a non-sym. eight-membered {¡¤¡¤¡¤HOCO}₂ synthon, and the second carboxylic acid of DTBA linked to the DMF mol. via a seven-membered {¡¤¡¤¡¤HOCO¡¤¡¤¡¤HCO} heterosynthon. The three-mol. aggregates are connected into a supramol. chain along the a axis. Supramol. layers in the ab plane are formed as the chains are linked via DMF-C-H¡¤¡¤¡¤S(DTBA) contacts, and these inter-digitate along the c-axis direction without specific points of contact between them. A Hirshfeld surface anal. points to addnl. but, weak contacts to stabilize the three-dimensional architecture: DTBA-C=O¡¤¡¤¡¤H(phenyl-DTBA), 2CBA-Cl¡¤¡¤¡¤H(phenyl-DTBA), as well as a ¦Ð-¦Ð contact between the delocalized eight-membered {¡¤¡¤¡¤HOC=O}₂ carboxylic dimer and the Ph ring of 2CBA. The latter was confirmed by electrostatic potential (ESP) mapping.

Acta Crystallographica, Section E: Crystallographic Communications published new progress about 119-80-2. 119-80-2 belongs to catalysis-chemistry, auxiliary class sulfides,Carboxylic acid,Benzene, name is 2,2′-Dithiodibenzoic acid, and the molecular formula is C10H16Br3N, Name: 2,2′-Dithiodibenzoic acid.

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