Month: February 2023

Markedly improved photo-oxidation stability of α form isotactic polypropylene with nodular morphology was written by Wu, Hao;Zhao, Ying;Su, Lili;Wang, Kezhi;Dong, Xia;Wang, Dujin. And the article was included in Polymer Degradation and Stability in 2021.Category: esters-buliding-blocks This article mentions the following:

Photo-oxidation degradation behaviors of isotactic polypropylene (iPP) films with different crystalline morphol. were investigated by artificially accelerated aging test. The α form iPP with nodular morphol. was obtained by quenching the melt and subsequent annealing process, and its photo-oxidation degradation behavior was compared with that of the melt-crystallized α form iPP sample. Fourier transform IR spectroscopy, gel permeation chromatog., differential scanning calorimetry, X-ray scattering, dynamic mech. anal. and at. force microscopy were utilized to characterize the microstructural variations of these two kinds of iPP films during photo-oxidation degradation process. The results showed that iPP film of nodular morphol. exhibits improved photo-oxidation stability compared with that of lamellar and spherulitic structure. UV-Vis spectra and O₂ diffusivity test of unexposed and aged samples demonstrated that the iPP film of nodular morphol. has higher transparency and lower O₂ diffusivity than that of lamellar morphol. Combining the microstructural anal. and surface morphol. observation, the improved photo-oxidation stability of “nodular” iPP was correlated with its higher UV light transparency, lower O₂ diffusion coefficient as well as the slower segmental mobility in the amorphous phase. In the experiment, the researchers used many compounds, for example, 2,2-Bis(((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyl)oxy)methyl)propane-1,3-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate) (cas: 6683-19-8Category: esters-buliding-blocks).

2,2-Bis(((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyl)oxy)methyl)propane-1,3-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate) (cas: 6683-19-8) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials.Category: esters-buliding-blocks

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Preparation and characterization of novel organic/inorganic hybrid nanoparticles containing an organotin core and a polystyrene shell was written by Jia, Yong-Guang;Jiang, Jian;Liu, Ling-Yan;Chang, Wei-Xing;Li, Jing. And the article was included in Journal of Applied Polymer Science in 2012.HPLC of Formula: 27249-90-7 This article mentions the following:

A series of well-defined nanoparticles containing an organotin core and a polystyrene shell were obtained by crosslinking of n-Bu₂SnO with amphiphilic styrene-[6-(4-vinylphenoxy)hexanoic acid] diblock copolymers with various mol. weights The amphiphilic copolymers were synthesized via reversible addition fragmentation chain transfer polymerization and hydrolysis. The structures of the nanoparticles were studied by the transmission electron microscopy, SEM, and XPS anal. The morphol. of the crosslinked copolymer showed individual nanoparticles with regularly spherical shape. And the nanoparticle diameters decreased with increasing number of organotin carboxylate units. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012. In the experiment, the researchers used many compounds, for example, Benzyl benzodithioate (cas: 27249-90-7HPLC of Formula: 27249-90-7).

Benzyl benzodithioate (cas: 27249-90-7) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits, including apples, durians, pears, bananas, pineapples, and strawberries. Cyclic esters are called lactones, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is γ-valerolactone.HPLC of Formula: 27249-90-7

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Characterization of the volatile compounds profile of the innovative broken oolong-black tea in comparison with broken oolong and broken black tea was written by Qi, Dandan;Miao, Aiqing;Chen, Wei;Wang, Wenwen;He, Xiugu;Ma, Chengying. And the article was included in Food Control in 2021.Product Details of 706-14-9 This article mentions the following:

Broken oolong-black tea is an innovative tea in China produced by applying characteristic manufacture crafts of broken oolong tea (bruising) and broken black tea (fermentation) on the manufacture of tea and it has both aroma features of broken oolong tea and broken black tea. The aim of this study is to investigate the differences of the volatile compounds among broken oolong-black, broken oolong and broken black tea made by Huangzhixiang (HZX) and Huangdan (HD) varieties by gas chromatog.-mass spectrometry (GC-MS) combined with chemometirc anal. The results suggested significant differences on both aroma quality and volatile compounds profile of three kinds of tea. Chemometric anal. showed that 47 and 52 differential volatile compounds were identified to distinguish three kinds of teas made by HZX and HD, resp., and the differences of volatile compounds among the tea samples were mostly quant. rather than qual. Besides, compounds with floral and fruity aroma increased in broken oolong-black tea compared with the others, while compounds with green aroma decreased in broken oolong-black tea. Quant. descriptive anal. of the aroma showed that sweet aroma was a new trait of broken oolong-black tea compared with broken oolong tea while green aroma disappeared compared with broken black tea. Our results provide the theor. and practical meaning for the application of two characteristic crafts from different tea manufacture on the innovation of tea manufacture In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Product Details of 706-14-9).

5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Liquid esters of low volatility serve as softening agents for resins and plastics. Esters also include many industrially important polymers. Polymethyl methacrylate is a glass substitute sold under the names Lucite and Plexiglas; polyethylene terephthalate is used as a film (Mylar) and as textile fibres sold as Terylene, Fortrel, and Dacron.Product Details of 706-14-9

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Comparison of different categories of Slovak Tokaj wines in terms of profiles of volatile organic compounds was written by Furdikova, Katarina;Machynakova, Andrea;Drtilova, Tereza;Spanik, Ivan. And the article was included in Molecules in 2020.Related Products of 118-61-6 This article mentions the following:

The present work deals with the characterization of volatile organic compounds in wines from the Slovak Tokaj wine region. Studied wine samples were divided into 3 groups-varietal wines from registered Tokaj vine varieties, film wines Tokajske samorodne dry, and naturally sweet botrytized wines Tokaj selections. The VOCs from wines were extracted using optimized solid phase microextraction and analyzed by comprehensive two-dimensional gas chromatog. coupled to high-resolution time-of-flight mass spectrometry (HRTOF-MS). In total, 176 VOCs were identified in all 46 studied samples. It was found that the total number of VOCs in varietal wines was generally higher than in botrytized wines. All three studied categories showed characteristic VOC profiles with significant differences. Varietal wines were characterized by higher concentrations of esters and terpenoids originating from grapes. The presence of γ-octalactone, (E)-6-methylhept-2-en-4-one, and lack of benzaldehyde were typical for Tokajske samorodne dry. Tokaj selections expressed the highest concentration of di-Et malate, benzaldehyde, and furfurals. Several interesting trends were also observed The concentration of fermentation products was highest in varietal wines, while long-term matured Tokaj special wines were typified by the presence of compounds related to noble-rotten raisins (2-phenylacetaldehyde, Et 2-phenylacetate, and 2-phenylethanol), wood (cis-whisky lactone), and aging (1,1,6-trimethyl-2H-naphthalene, furfural, and 5-methylfurfural). In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxybenzoate (cas: 118-61-6Related Products of 118-61-6).

Ethyl 2-hydroxybenzoate (cas: 118-61-6) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials.Related Products of 118-61-6

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Pillar[5]arene-Based Polycationic Glyco[2]rotaxanes Designed as Pseudomonas aeruginosa Antibiofilm Agents was written by Mohy El Dine, Tharwat;Jimmidi, Ravikumar;Diaconu, Andrei;Fransolet, Maude;Michiels, Carine;De Winter, Julien;Gillon, Emilie;Imberty, Anne;Coenye, Tom;Vincent, Stephane P.. And the article was included in Journal of Medicinal Chemistry in 2021.Quality Control of (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate This article mentions the following:

Pseudomonas aeruginosa (P.A.) is a human pathogen belonging to the top priorities for the discovery of new therapeutic solutions Its propensity to generate biofilms strongly complicates the treatments required to cure P. A. infections. Herein, we describe the synthesis of a series of novel rotaxanes composed of a central galactosylated pillar[5]arene, a tetrafucosylated dendron, and a tetraguanidinium subunit. Besides the high affinity of the final glycorotaxanes for the two P. A. lectins LecA and LecB, potent inhibition levels of biofilm growth were evidenced, showing that their three subunits work synergistically. An antibiofilm assay using a double LecA and LecB mutant compared to the wild type demonstrated that the antibiofilm activity of the best glycorotaxane is lectin-mediated. Such antibiofilm potency had rarely been reached in the literature. Importantly, none of the final rotaxanes was bactericidal, showing that their antibiofilm activity does not depend on bacteria killing, which is a rare feature for antibiofilm agents. In the experiment, the researchers used many compounds, for example, (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4Quality Control of (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate).

(2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4) belongs to esters. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. Esters are more polar than ethers but less polar than alcohols. They participate in hydrogen bonds as hydrogen-bond acceptors, but cannot act as hydrogen-bond donors, unlike their parent alcohols. This ability to participate in hydrogen bonding confers some water-solubility.Quality Control of (2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Effect of roasting temperature and time on volatile compounds, total tocopherols, and fatty acids of flaxseed oil was written by Sun, Xuelian;Zhang, Bo;Han, Jiajia;Wei, Changqing;Liu, Wenyu. And the article was included in Journal of Food Science in 2022.Product Details of 695-06-7 This article mentions the following:

Roasting affects the physicochem. and nutritional qualities of flaxseed oil (FSO). The FSO samples were extracted from the roasting flaxseeds at 10-, 20-, and 30-min points and at different temperatures (140°C, 160°C, and 180°C). A total of 61 volatile compounds were identified, and the quantity of the volatile compounds increased significantly (p < 0.05) after roasting. The maximum aldehyde (25.83%) and heterocyclic content (29.26%) was obtained from the samples roasted at 200°C for 20 and 30 min, resp. The predominant fatty acid in FSO samples was linolenic acid (46.01%-49.35%), which changed dynamically during roasting. The loss of α-, γ-, and δ-tocopherol after roasting was 28.73, 109.78, and 6.67 mg/100 g, resp. The principal component anal. and hierarchical cluster anal. results showed good discrimination of the different FSO samples into three groups, which were mainly related to the roasting time. Therefore, it can be concluded that roasting time has a stronger effect on the volatile composition of FSO than the temperature during the roasting process. This work provides a basis for improving the aroma of FSO. The roasting process is used to extract flaxseed oil (FSO) from flaxseeds. Studying the physicochem. properties and quality characteristics of FSO under diverse roasting conditions is an important step in producing FSO in the food industry, which can give precise instructions to produce flaxseed oil in factories. The results of this study document the volatile constituents generated in FSO samples extracted from flaxseeds during roasting, which may help manufacturers, who are trying to develop natural and artificial FSO flavors. In the experiment, the researchers used many compounds, for example, 5-Ethyldihydrofuran-2(3H)-one (cas: 695-06-7Product Details of 695-06-7).

5-Ethyldihydrofuran-2(3H)-one (cas: 695-06-7) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits. Because of their lack of hydrogen-bond-donating ability, esters do not self-associate. Consequently, esters are more volatile than carboxylic acids of similar molecular weight.Product Details of 695-06-7

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Copper-Catalyzed Cascade Cyclization of Indolyl Homopropargyl Amides: Stereospecific Construction of Bridged Aza-[n.2.1] Skeletons was written by Tan, Tong-De;Zhu, Xin-Qi;Bu, Hao-Zhen;Deng, Guocheng;Chen, Yang-Bo;Liu, Rai-Shung;Ye, Long-Wu. And the article was included in Angewandte Chemie, International Edition in 2019.Quality Control of Methyl 2-thienylacetate This article mentions the following:

Catalytic cycloisomerization-initiated cascade cyclizations of terminal alkynes have received tremendous interest, and been widely used in the facile synthesis of a diverse array of valuable complex heterocycles. However, these tandem reactions have been mostly limited to noble-metal catalysis, and are initiated by an exo-cyclization pathway. Reported herein is an unprecedented copper-catalyzed endo-cyclization-initiated tandem reaction of indolyl homopropargyl amides, where copper catalyzes both the hydroamination and Friedel-Crafts alkylation process [e.g., I → II (85%)]. This method allows the practical and atom-economical synthesis of valuable bridged aza-[n.2.1] skeletons (n=3-6) with wide substrate scope, and excellent diastereoselectivity and enantioselectivity by a chirality-transfer strategy. Moreover, the mechanistic rationale for this novel cascade cyclization is also strongly supported by control experiments, and is distinctively different from the related gold catalysis. In the experiment, the researchers used many compounds, for example, Methyl 2-thienylacetate (cas: 19432-68-9Quality Control of Methyl 2-thienylacetate).

Methyl 2-thienylacetate (cas: 19432-68-9) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits, including apples, durians, pears, bananas, pineapples, and strawberries. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Quality Control of Methyl 2-thienylacetate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

NMR investigation into inter- and intramolecular interactions in substituted trifluoromethylphenylisocyanate, fluorophenylisocyanate, fluoroaniline, and fluoronitrobenzene was written by Kosfeld, R.;Henke, L.. And the article was included in Organic Magnetic Resonance in 1976.Application of 60221-81-0 This article mentions the following:

The effects of temperature and solvent (CCl4) concentration on the chem. shifts of 1H and F signal of the title compounds (I-IV, resp.) were investigated. In ortho substituted I the temperature effect on the F chem. shift arose from intramol. interaction of the CF3 group with the ortho substituent; rising temperature led to an increase in chem. shift. The temperature dependence of the electron distribution of meta and para substituted I was attributed to intermol. interactions; rising temperature thus led to a decrease in chem. shift. Protons showed a temperature dependence of the chem. shifts due to Van der Waals effects; increasing the amount of CCl4 led to a weakening of the anisotropy effect and an increase in the chem. shifts of both F and 1H signals. In the experiment, the researchers used many compounds, for example, 1-Fluoro-3-isocyanato-2-methylbenzene (cas: 60221-81-0Application of 60221-81-0).

1-Fluoro-3-isocyanato-2-methylbenzene (cas: 60221-81-0) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Esterification is the general name for a chemical reaction in which two reactants (typically an alcohol and an acid) form an ester as the reaction product. Esters are common in organic chemistry and biological materials.Application of 60221-81-0

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Chemical composition, antibiofilm, cytotoxic, and anti-acetylcholinesterase activities of Myrtus communis L. leaves essential oil was written by Caputo, Lucia;Capozzolo, Francesca;Amato, Giuseppe;De Feo, Vincenzo;Fratianni, Florinda;Vivenzio, Giovanni;Nazzaro, Filomena. And the article was included in BMC Complementary Medicine and Therapies in 2022.Application of 105-87-3 This article mentions the following:

The potential of essential oils (EOs) and of their principal constituents for eradication of biofilm and at the same time the research of new potential acetylcholinesterase inhibitors is gaining increasing interest in last years. The aims of this study were to determine the chem. composition and to evaluate the antibacterial, cytotoxic, and anti-acetylcholinesterase properties of Myrtus communis leaves essential oil and its main constituents. Essential oil was obtained by hydrodistillation of M. communis L. leaves and was analyzed by GC and GC-MS. The antimicrobial activity was carried out against both gram-neg. and gram-pos. bacteria. The microdilution method was used to estimate the min. inhibitory concentrations (MICs). Then, the capacity of essential oil and its main constituent to inhibit biofilm growth, with the method of OToole and Kolterand, and the metabolic activity of biofilm cells through the MTT colorimetric method were evaluated at different times. Moreover, was studied the potential cytotoxic activity against SH-SY5Y cell line with MTT assay and the anti-acetylcholinesterase activity using Ellmans assay. Myrtenyl-acetate, 1,8 cineole, α-pinene, and linalool were the main components in the EO. The myrtle EO, at the min. tested dose (0.4 mg/mL), inhibited S. aureus biofilm by 42.1% and was capable of inhibiting the biofilm cell metabolism in all tested strains, except Staphylococcus aureus. Moreover, the EO showed good cytotoxic and anti-acetylcholinesterase activities IC50 of 209.1 and 32.8μg/mL, resp. The results suggest that myrtle EO and its main constituents could be used as possible products that could act against the resistant pathogenic species E. coli, P. aeruginosa, L. monocytogenes and S. aureus, on the other hand, as possible coadjutants in the treatment of neurol. diseases. In the experiment, the researchers used many compounds, for example, (E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3Application of 105-87-3).

(E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Application of 105-87-3

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Aerobic oxygenation of olefinic compounds to the corresponding α-hydroxy ketones using an osmium tetroxide-nickel(II) complex catalyst system was written by Takai, Toshihiro;Yamada, Tohru;Mukaiyama, Teruaki. And the article was included in Chemistry Letters in 1991.HPLC of Formula: 19444-23-6 This article mentions the following:

In the presence of the catalyst system OsO₄-bis(3-methyl-2,4-pentanedionato)nickel(II), various olefinic compounds are directly converted to α-hydroxy ketones in good yields with O₂ and an aldehyde. In the experiment, the researchers used many compounds, for example, Benzyl 2-hydroxy-2-methylpropanoate (cas: 19444-23-6HPLC of Formula: 19444-23-6).

Benzyl 2-hydroxy-2-methylpropanoate (cas: 19444-23-6) belongs to esters. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. Acyl chlorides and acid anhydrides alcoholysis is another way to produce esters. Acyl chlorides and acid anhydrides react with alcohols to produce esters. Anydrous conditions are recommended since both acyl chlorides and acid anhydrides react with water.HPLC of Formula: 19444-23-6

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics