Month: December 2022

Launay, Valentin published the artcileSafe near infrared light for fast polymers surface sterilization using organic heaters, Product Details of C15H20O6, the publication is Materials Chemistry Frontiers (2022), 6(9), 1172-1179, database is CAplus.

Sterilization approaches using UV radiation (e.g. 254 nm), dry heat and moist heat have been widely reported in the literature. A breakthrough approach is presented here. In the present study, we proposed a most environmentally friendly approach for polymer surface sterilization using safe Near-IR (NIR) light to produce a powerful photothermal effect using organic NIR dyes as heaters. Markedly, well selected organic dyes strongly absorbing in the NIR range have been used as stimuli responsive compounds When excited upon NIR light, these heaters release the light energy to their surrounding environment in the form of heat. In this work, trimethylolpropane triacrylate (TMPTA) based polymers, used as benchmark materials for polymers or coatings, could reach high temperatures (>120°C) in a very short time scale (∼30 s). Using heater-containing polymers, sterilization experiments showed very good results with total eradication of bacteria (Escherichia coli) after only 2 min of NIR irradiation (2.55 W cm^-2). These results suggest that short irradiation flashes could be enough to sterilize contaminated surfaces. Moreover, irradiation tests have been performed on three NIR heaters in the NIR-II range (1000-1700 nm) for a better in-depth penetration. Indeed, almost 200°C could be reached by polymers in less than 1 min of NIR irradiation (2.5 W cm^-2). Therefore, NIR LED irradiation of heater-containing polymers constitutes here a robust, transportable and safe sterilization method.

Materials Chemistry Frontiers published new progress about 15625-89-5. 15625-89-5 belongs to esters-buliding-blocks, auxiliary class Polymerization Reagents,Crosslinkers, name is Trimethylolpropane triacrylate, and the molecular formula is C15H20O6, Product Details of C15H20O6.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Garra, Patxi published the artcilePeroxide-Free and Amine-Free Redox Free Radical Polymerization: Metal Acetylacetonates/Stable Carbonyl Compounds for Highly Efficient Synthesis of Composites, Product Details of C6H8O3, the publication is Macromolecules (Washington, DC, United States) (2018), 51(16), 6395-6404, database is CAplus.

New peroxide-free, amine-free, and phosphine-free redox free radical polymerization (RFRP) initiating systems comprising remarkably stable (i) metal acetylacetonates (Mn(acac)₃, Cu(acac)₂) and (ii) carbonyl compounds bearing labile hydrogen in the α-position are presented for polymerization initiation under mild conditions (under air, at room temperature, nonpurified monomers). The systems proposed in this work are competitive or even outranked the well-known peroxide-based RFRP reference in several criteria: (i) toxicity, (ii) stability, (iii) surface curing, (iv) overall double-bond conversions, and (v) workability of the RFRP mixture (longer gel times are now possible). Radical initiating reactions are studied using many complementary exptl./theor. techniques: optical pyrometry, thermal imaging, Raman confocal microscopy, ESR (ESR), ESR spin trapping (ESR-ST), high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), d. functional theory (DFT), simulations of bond dissociation energies (BDE), reaction enthalpies, and DFT simulations of seven unknown ESR-ST adducts. A full consistent picture of the chem. mechanisms involved in these new redox systems is provided.

Macromolecules (Washington, DC, United States) published new progress about 517-23-7. 517-23-7 belongs to esters-buliding-blocks, auxiliary class Tetrahydrofuran,Ketone,Ester, name is 3-Acetyldihydrofuran-2(3H)-one, and the molecular formula is C6H8O3, Product Details of C6H8O3.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Rasgele, Pinar Goc published the artcileChemical Compositions and Antimutagenic Effects of Ethanolic Extracts of Stachys thirkei and Stachys Annua subsp. Annua Using the Ames Assay, COA of Formula: C5H10O2S, the publication is Pharmaceutical Chemistry Journal (2021), 54(12), 1255-1262, database is CAplus.

In this study, antimutagenic effects of ethanolic extracts of Stachys thirkei and Stachys annua subsp. annua belonging to Lamiaceae family that grow in Duzce of Turkey were investigated on Salmonella typhimurium TA98 and TA100 strains without metabolic activation using Salmonella/microsome test system. Three different concentrations (0.025, 0.05 and 0.1 mg/plate) of the ethanolic extracts of S. thirkei and S. annua subsp. were used as active materials in which the major components were 2-ethylhexanol (30.012%) and 2-beta-pinene (26.40%), resp. The highest concentration (0.1 mg/plate) of S. thirkei had a moderate antimutagenic effect on the Salmonella typhimurium TA98 strain with a 26.79% inhibition rate. It was also established that the extract of S. thirkei at highest concentration (0.1 mg/plate) exhibited strong antimutagenic effect (with 44.03% maximum inhibition) on TA100 strain. Furthermore, it was found that 0.05 mg/plate ethanolic extract showed moderate antimutagenic activity with 25.55% inhibition rate. The highest concentration (0.1 mg/plate) of ethanolic extract of S. annua subsp. showed moderate antimutagenic activity on both Salmonella typhimurium TA98 and TA100 strains with inhibition rates of 20.39 and 22.13%, resp. No antimutagenic activity on Salmonella typhimurium TA98 and TA100 strains was observed at the lowest doses of both plant species. As a result, it is concluded that S. thirkei and annua subsp. have antimutagenic activity and further studies may be recommended in terms of different parameters.

Pharmaceutical Chemistry Journal published new progress about 19788-49-9. 19788-49-9 belongs to esters-buliding-blocks, auxiliary class Thiol,Aliphatic hydrocarbon chain,Ester, name is Ethyl 2-mercaptopropanoate, and the molecular formula is C5H10O2S, COA of Formula: C5H10O2S.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Dullin, Anja published the artcileSynthesis and cytotoxicity of enantiomerically pure [1,2-diamino-1-(4-fluorophenyl)-3-methylbutane]platinum(II) complexes, HPLC of Formula: 106391-88-2, the publication is ChemMedChem (2006), 1(6), 644-653, database is CAplus and MEDLINE.

A series of leaving group derivatives of enantiomerically pure [1,2-diamino-1-(4-fluorophenyl)-3-methylbutane]platinum(II) complexes were synthesized and tested for cytotoxicity. The enantiomeric purity was determined by ¹H NMR spectroscopy on the final diamines after derivation with (1R)-myrtenal. For coordination to platinum, the diamines were reacted with K₂Ptl₄. The treatment of diiodoplatinum(II) complexes (4F-Ph/iProp-Ptl₂) with Ag₂SO₄ resulted in the sulfatoplatinum(II) complexes (4F-Ph/iProp-PtSO₄), which can be easily transformed to dichloroplatinum(II) complexes (4F-Ph/iProp-PtCl₂) with 2 N HCl. The importance of the leaving groups and the configuration at the diamine ligand on the antiproliferative effects was evaluated on the hormone-dependent MCF-7 and the hormone-independent MDA-MB 231 breast cancer cell lines as well as the LNCaP/FGC prostate cancer cell line. (R,R)-4F-Ph/iProp-PtCl₂ was identified as the most active platinum(II) complex. The 3-Me group increased antiproliferative effects relative to the [1,2-diamino-1-(4-fluorophenyl)butane]platinum(II) complexes described in an earlier study.

ChemMedChem published new progress about 106391-88-2. 106391-88-2 belongs to esters-buliding-blocks, auxiliary class Amine,Aliphatic hydrocarbon chain,Amide,Aldehyde, name is (R)-tert-Butyl (3-methyl-1-oxobutan-2-yl)carbamate, and the molecular formula is C10H19NO3, HPLC of Formula: 106391-88-2.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Lamiot, Eric published the artcileInsect Sex Pheromone Binding by Bovine β-Lactoglobulin, Related Products of esters-buliding-blocks, the publication is Journal of Agricultural and Food Chemistry (1994), 42(3), 695-9, database is CAplus.

The binding of 24 derivatives of Cydia pomonella sex pheromone (dodecanol framework with 0, 1, or 2 conjugated double bonds at different positions of the aliphatic chain) and SDS to unmodified, acylated, alkylated, and esterified β-lactoglobulin (BLG) was studied by fluorescence spectrophotometry. Their apparent dissociation constants were in the range 0.2-0.9 × 10^-6 M (apparent molar ratio ca. 1). Dodecyl acetate and SDS displayed the highest affinity for BLG, when (E,E)-6,8-dodecadienyl acetate and (E,E)-7,9-dodecadienyl acetate did not bind to BLG in the applied conditions. The apparent dissociation constants of derivatives unconstrained by conjugated double bonds did not differ. The BLG binding affinity of other studied pheromone derivatives depends on the number of double bonds, their position in the aliphatic chain, and their isomerization (Z or E). Since, neither (E)-3-dodecenyl acetate nor (Z,E)-8,10-dodecadienyl acetate nor retinol binding constants changed during their simultaneous binding by BLG, it was concluded that they bind in different binding sites on the BLG mol. The chem. modifications that increased the hydrophobicity of BLG prevented its binding of the apolar ligand pheromone mols.

Journal of Agricultural and Food Chemistry published new progress about 16974-11-1. 16974-11-1 belongs to esters-buliding-blocks, auxiliary class Aliphatic Chain, name is (Z)-Dodec-9-en-1-yl acetate, and the molecular formula is C14H26O2, Related Products of esters-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Birkholz, Mandy-Nicole published the artcileEnantioselective hydrogenation with self-assembling rhodium phosphane catalysts: influence of ligand structure and solvent, Application In Synthesis of 126613-06-7, the publication is Chemistry – A European Journal (2007), 13(20), 5896-5907, database is CAplus and MEDLINE.

Three sets of new and related chiral phospholane and phosphepine ligands were prepared for Rh-catalyzed enantioselective hydrogenation. The size and substitution pattern of the cyclic monophosphines were varied. More importantly, the ligands differ in the nature of the heterocyclic group linked to the trivalent P atom: 2-pyridone or 2-alkoxypyridine. In the corresponding Rh complexes, the pyridone units of two monodentate P ligands can assemble by H bonding and form chelates. In contrast, synthetic precursors bearing alkoxypyridine appendages are not able to aggregate via intramol. H bonds. The nature of self-assembly is dependent on the nature of the P ligand and the solvent used for the hydrogenation (CH₂Cl₂ vs. MeOH). These features affect the rate of the reaction as well as the enantioselectivity, which varied at 0-99% ee. Complexation studies and DFT calculations were performed to explain these differences.

Chemistry – A European Journal published new progress about 126613-06-7. 126613-06-7 belongs to esters-buliding-blocks, auxiliary class Chiral Diphenols, name is (R)-[1,1′-Binaphthalene]-2,2′-diyl bis(trifluoromethanesulfonate), and the molecular formula is C22H12F6O6S2, Application In Synthesis of 126613-06-7.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Lion, Claude published the artcileSynthesis of hindered acid chlorides. Study of their condensation with Grignard reagents in the presence of copper salts. Preparation of highly branched ketones, Recommanded Product: Ethyltert-butylacetate, the publication is Journal of Chemical Research, Synopses (1978), 46, database is CAplus.

Sequential treatment of RCH₂CO₂R¹ (I; R = iso-Pr, R¹ = H) with R²X (R² = Me, Et, X = halide), SOCl₂, and EtOH gave 97-8% RCHR²CO₂Et (II). Similar alkylation of I (R = Me₃C, R¹ = Et) gave 92-6% II (R = Me₃C, R² = Me, Et). Further alkylation of the esters II (R = iso-Pr, Me₃C, R² = Me, Et) with R³X (R³ = iso-Pr, Et, X = halide) gave 32-81% RCR²R³CO₂Et, which on saponification gave 78-91% RCR²R³CO₂H (III). Treatment of III (R = iso-Pr, Me₃C, R² = Me, Et, R³ = iso-Pr; R = Me₃C, R² = R³ = Et) with SOCl₂ gave the corresponding acid chlorides which reacted with R⁴MgX (R⁴ = Me, X = I; R = neopentyl, Me₃C, X = Cl) in presence of CuCl to give 39-93% RCR²R³COR⁴.

Journal of Chemical Research, Synopses published new progress about 5340-78-3. 5340-78-3 belongs to esters-buliding-blocks, auxiliary class Aliphatic Chain, name is Ethyltert-butylacetate, and the molecular formula is C8H16O2, Recommanded Product: Ethyltert-butylacetate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

MacPhee, John A. published the artcileSteric limits to ester alkylation; synthesis of highly hindered esters via hexamethylphosphoramide-favored enolization, SDS of cas: 5340-78-3, the publication is Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) (1977), 694-6, database is CAplus.

The steric limits to alkylation of carboxylic esters by alkyl iodides with LiN(CHMe2)2 as base in the presence of (Me2N)3PO were studied using a modification of R. H. Schlessinger et al. (1973) and the influence of (Me2N)3PO inpromoting ester enolization, as opposed to its influence on the alkylation step, was examined The formation of α,α-disubstituted from α-monosubstituted esters takes place in high yield and is only slightly influenced by the nature of the alkylating agent, whereas the formation of α,α,α-trisubstituted from α,α-disubstituted esters is sensitive to the steric nature of the ester to be alkylated. Thus in the synthesis of trisubstituted from monosubstituted esters the order of introduction of alkyl groups is critical. The failure of esters to react is interpreted by an inability to undergo enolization.

Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999) published new progress about 5340-78-3. 5340-78-3 belongs to esters-buliding-blocks, auxiliary class Aliphatic Chain, name is Ethyltert-butylacetate, and the molecular formula is C8H16O2, SDS of cas: 5340-78-3.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Gingras, Marc published the artcileSynthesis of carbohelicenes and derivatives by “carbenoid couplings”, Quality Control of 126613-06-7, the publication is Tetrahedron Letters (1999), 40(7), 1309-1312, database is CAplus.

Short synthetic sequences to helicenes have been achieved under thermal conditions, without using photochem. and high dilution Couplings of aromatic bis(bromomethyl) moieties, in the presence of an excess of LiHMDS, are key reactions in the final ring closures to helicenes. These optimized, quick and efficient reactions occur at 0°C within 10 min. and often provide [5]-helicene, [5]-helicene derivatives and [7]-helicene in ∼75% yield. Preliminary data questioned the formation of carbenoid anions and carbenes in the so called “carbenoid couplings”.

Tetrahedron Letters published new progress about 126613-06-7. 126613-06-7 belongs to esters-buliding-blocks, auxiliary class Chiral Diphenols, name is (R)-[1,1′-Binaphthalene]-2,2′-diyl bis(trifluoromethanesulfonate), and the molecular formula is C22H12F6O6S2, Quality Control of 126613-06-7.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Liu, Zhipeng published the artcileMechanism of boron carbide particles improving the wear resistance of UHMWPE: Structure-property relationship, Safety of Tris(2,4-di-tert-butylphenyl) phosphite, the publication is Polymer (2022), 124733, database is CAplus.

Inorganic particles are often used to enhance the wear resistance of UHMWPE, but the mechanism of the “enhancement effect” of inorganic particles improving the wear resistance of UHMWPE is ambiguous. In this paper, boron carbide particles(B₄C) were used to improve the wear resistance of UHMWPE, it was found that the wear resistance of UHMWPE was increased by up to 46% with appropriate filler loading of B₄C. Subsequently, the mechanism of B₄C improving the wear resistance of UHMWPE was studied and illustrated from the perspective of structure-property relationship. The B₄C particles act as exotic entanglement points, forming an entanglement network of particle-coupling agent-matrix, improving the degree of entanglement of mol. chains in the amorphous region of UHMWPE, thus improving the shear resistance of the matrix and reducing the structure damage caused by strong shearing during friction. Meanwhile, the highly entangled mol. chains prevented the transition of the interphase to the crystalline region, thus increasing the content of the interphase of UHMWPE and consequently alleviating the structural damage during the friction. Furthermore, B₄C particles played the role of load bearing, which enhanced the compression resistance of UHMWPE then reduced the structure damage caused by compression in the normal upward during friction. This paper could be helpful to better understand the role of fillers on the wear resistance of UHMWPE and provide theor. guidance to improve the wear resistance of UHMWPE and other materials.

Polymer published new progress about 31570-04-4. 31570-04-4 belongs to esters-buliding-blocks, auxiliary class Mono-phosphine Ligands, name is Tris(2,4-di-tert-butylphenyl) phosphite, and the molecular formula is C42H63O3P, Safety of Tris(2,4-di-tert-butylphenyl) phosphite.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics