Month: February 2023

The evaluation of solid phase micro-extraction fibre types for the analysis of organic components in unburned propellant powders was written by Dalby, Oliver;Birkett, Jason W.. And the article was included in Journal of Chromatography A in 2010.COA of Formula: C12H22O4 This article mentions the following:

This work describes the evaluation of various solid phase micro-extraction (SPME) fiber types for the detection of compounds originating from particles of unburned propellant powders. These compounds may also be found in association with organic gunshot residues (OGSR). Seven SPME fibers were assessed based on their ability to extract the compounds of interest (diphenylamine (DPA), 4-nitrodiphenylamine (4-NDPA), Et centralite (EC), nitroglycerin (NG) and di-Bu phthalate (DBP)) from four ammunition types across three calibres (9 mm, 5.56 mm and 7.62 mm). Extracts were analyzed by gas chromatog./mass spectrometry (GC/MS). The 65 μm polydimethylsiloxane/divinylbenzene (PDMS/DVB) was the most suitable fiber type for the extraction of these compounds across the ammunition types tested. Optimal extraction time parameters were also assessed with a 35-min period determined to be suitable. A number of previously unreported considerations for extracting propellant powders and potentially OGSR related materials are discussed. In the experiment, the researchers used many compounds, for example, Dimethyl decanedioate (cas: 106-79-6COA of Formula: C12H22O4).

Dimethyl decanedioate (cas: 106-79-6) 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. 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.COA of Formula: C12H22O4

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

Identification of aroma-active compounds in Cheddar cheese imparted by wood smoke was written by Rizzo, P. V.;Del Toro-Gipson, R. S.;Cadwallader, D. C.;Drake, M. A.. And the article was included in Journal of Dairy Science in 2022.Related Products of 695-06-7 This article mentions the following:

Cheddar cheese is the most popular cheese in the United States, and the demand for specialty categories of cheese, such as smoked cheese, are rising. The objective of this study was to characterize the flavor differences among Cheddar cheeses smoked with hickory, cherry, or apple woods, and to identify important aroma-active compounds contributing to these differences. First, the aroma-active compound profiles of hickory, cherry, and apple wood smokes were analyzed by solid-phase microextraction (SPME) gas chromatog.-olfactometry (GCO) and gas chromatog.-mass spectrometry (GC-MS). Subsequently, com. Cheddar cheeses smoked with hickory, cherry, or apple woods, as well as an unsmoked control, were evaluated by a trained sensory panel and by SPME GCO and GC-MS to identify aroma-active compounds Selected compounds were quantified with external standard curves. Seventy-eight aroma-active compounds were identified in wood smokes. Compounds included phenolics, carbonyls, and furans. The trained panel identified distinct sensory attributes and intensities among the 3 cheeses exposed to different wood smokes (P < 0.05). Hickory smoked cheeses had the highest intensities of flavors associated with characteristic “smokiness” including smoke aroma, overall smoke flavor intensity, and meaty, smoky flavor. Cherry wood smoked cheeses were distinguished by the presence of a fruity flavor. Apple wood smoked cheeses were characterized by the presence of a waxy, green flavor. Ninety-nine aroma-active compounds were identified in smoked cheeses. Phenol, guaiacol, 4-methylguaiacol, and syringol were identified as the most important compounds contributing to characteristic “smokiness.” Benzyl alc. contributed to the fruity flavor in cherry wood smoked cheeses, and 2-methyl-2-butenal and 2-ethylfuran were responsible for the waxy, green flavor identified in apple wood smoked cheeses. These smoke flavor compounds, in addition to diacetyl and acetoin, were deemed important to the flavor of cheeses in this study. from this study identified volatile aroma-active compounds contributing to differences in sensory perception among Cheddar cheeses smoked with different wood sources. In the experiment, the researchers used many compounds, for example, 5-Ethyldihydrofuran-2(3H)-one (cas: 695-06-7Related Products 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. 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.Related Products of 695-06-7

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

Geraniol and Citral as potential therapeutic agents targeting the HSP90 activity: An in silico and experimental approach was written by Gaonkar, Roopa;Singh, Jitender;Chauhan, Arushi;Avti, Pramod K.;Hegde, Gurumurthy. And the article was included in Phytochemistry (Elsevier) in 2022.Recommanded Product: (E)-3,7-Dimethylocta-2,6-dien-1-yl acetate This article mentions the following:

Lemongrass essential oil has antifungal and anti-cancerous properties. Heat-shock protein (HSP90), an ATP-dependent mol. chaperone found in eukaryotes, is involved in protein folding, stability, and disease, making it a promising research topic. Both in silico and in vitro approaches were used to provide a clear insight into the HSP90-ATPase 3D structures, activity, and their interaction with the essential oil constituents among various species such as fungi (S. cerevisiae), parasites (P. falciparum), and humans. For in silico studies, sequence alignment, docking (AutoDock), and absorption, distribution, metabolism, and excretion (ADME) properties were evaluated to obtain hit compounds specifically against each HSP90-ATPase. The hit compounds obtained were evaluated for their efficacy in the in vitro studies of S. cerevisiae. In vitro studies were carried out targeting HSP90-ATPases via lemongrass essential oil components individually and in combination as a function of concentration and various salt concentrations Results suggest that sequence alignment exists of over 75% among these three species. The best docking score was possessed by Geraniol and its constituent (geldanamycin â‰?-4.93 kcal/mol) (a known antifungal and antitumor against HSP90) in all the above species. Lemongrass oil and the combination of Geraniol and Citral at concentrations of 80μg/mL showed the maximum inhibition of ATPase and HSP90-ATPase activity compared to their individual treatment. Therefore, both in silico and in vitro studies provide clear evidence of specific inhibitory action of lemongrass oil, Geraniol, and Citral against the ATPase and HSP90-ATPase activities and might show potential as antifungal and antitumor drugs. In the experiment, the researchers used many compounds, for example, (E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3Recommanded Product: (E)-3,7-Dimethylocta-2,6-dien-1-yl acetate).

(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. 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.Recommanded Product: (E)-3,7-Dimethylocta-2,6-dien-1-yl acetate

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

Strategy for Good Dispersion of Well-Defined Tetrapods in Semiconducting Polymer Matrices was written by Lim, Jaehoon;Borg, Lisa zur;Dolezel, Stefan;Schmid, Friederike;Char, Kookheon;Zentel, Rudolf. And the article was included in Macromolecular Rapid Communications in 2014.Computed Properties of C14H12S2 This article mentions the following:

The morphol. or dispersion control in inorganic/organic hybrid systems is studied, which consist of monodisperse CdSe tetrapods (TPs) with grafted semiconducting block copolymers with excess polymers of the same type. Tetrapod arm-length and amount of polymer loading are varied in order to find the ideal morphol. for hybrid solar cells. Addnl., polymers without anchor groups are mixed with the TPs to study the effect of such anchor groups on the hybrid morphol. A numerical model is developed and Monte Carlo simulations to study the basis of compatibility or dispersibility of TPs in polymer matrixes are performed. The simulations show that bare TPs tend to form clusters in the matrix of excess polymers. The clustering is significantly reduced after grafting polymer chains to the TPs, which is confirmed exptl. Transmission electron microscopy reveals that the block copolymer-TP mixtures (“hybrids”) show much better film qualities and TP distributions within the films when compared with the homopolymer-TP mixtures (“blends”), representing massive aggregations and cracks in the films. This grafting-to approach for the modification of TPs significantly improves the dispersion of the TPs in matrixes of “excess” polymers up to the arm length of 100 nm. In the experiment, the researchers used many compounds, for example, Benzyl benzodithioate (cas: 27249-90-7Computed Properties of C14H12S2).

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. 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.Computed Properties of C14H12S2

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

Volatile Composition of Juniperus pingii var. wilsonii and Its Inhibitory Effect on Nitric Oxide Production of Macrophage Cells was written by Zhu, Mengxia;Ling, Lijun;De, Ji;Lu, Yan;Chen, Daofeng. And the article was included in Journal of Essential Oil-Bearing Plants in 2018.Quality Control of Isopentyl 3-methylbutanoate This article mentions the following:

The leaves and twigs of Juniperus pingii var. wilsonii (Cupressaceae) smell aromatic and are traditionally used as the Tibetan medicine Xuba. Their essential oil obtained by ultrasonic-assisted hydrodistillation and volatiles collected by GC headspace technique were analyzed and compared by GC-MS. The analyses revealed the presence of thirty-nine components in the essential oil, representing 95.8% in content of the total oil, mainly including sabinene (22.6%), elemol (15.5%) and (-)-terpinen-4-ol (9.6%). Thirty-eight components accounting for 99.4% of the headspace volatiles were identified, mainly including sabinene (32.5%), β-pinene (21.9%) and α-thujene (10.3%). The compositions of the oil and headspace volatiles were quite similar, and twenty-five compounds identified were in common, which was 91.3% of the oil and 96.0% of the headspace volatiles in content. The essential oil could obviously inhibit Nitric oxide production in LPS-stimulated RAW 264.7 cells with no significant effect on cell viability, indicating its good anti-inflammatory activity. In the experiment, the researchers used many compounds, for example, Isopentyl 3-methylbutanoate (cas: 659-70-1Quality Control of Isopentyl 3-methylbutanoate).

Isopentyl 3-methylbutanoate (cas: 659-70-1) 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 contain a carbonyl center, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Quality Control of Isopentyl 3-methylbutanoate

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

Oligoamides from dodecanedioic acid and 4,4′-methylenedicyclohexylamine. (Oligoamides of the “Qiana” type) was written by Hahn, Guenther Erhard;Kusch, Peter;Rossbach, Volker;Zahn, Helmut. And the article was included in Makromolekulare Chemie in 1985.Formula: C13H24O4 This article mentions the following:

Pure isomers of cyclic monomeric amides were synthesized by cyclocondensation of 1,10-dodecanedioyl dichloride  [4834-98-4] and trans,trans– [6693-29-4], cis,trans– [6693-30-7], and cis,cis-4,4‘-methylenedicyclohexylamine  [6693-31-8] and were characterized by ¹H NMR, IR and mass spectroscopy, as well as by HPLC and x-ray diffraction. The content of these cyclic amides in Qiana nylon fibers was determined by fractionated extraction and sublimation. Synthesis and properties of monomeric linear condensation products containing dodecanedioyl and methylenedicyclohexylamine units (dicarboxylic acid-type with blocked and free end groups) were also described. In the experiment, the researchers used many compounds, for example, 12-Methoxy-12-oxododecanoic acid (cas: 3903-40-0Formula: C13H24O4).

12-Methoxy-12-oxododecanoic acid (cas: 3903-40-0) 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. Esters contain a carbonyl center, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. Formula: C13H24O4

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

Combining Inducible Lectin Expression and Magnetic Glyconanoparticles for the Selective Isolation of Bacteria from Mixed Populations was written by Petch, Joshua E.;Gurnani, Pratik;Yilmaz, Gokhan;Mastrotto, Francesca;Alexander, Cameron;Heeb, Stephan;Camara, Miguel;Mantovani, Giuseppe. And the article was included in ACS Applied Materials & Interfaces in 2021.Synthetic Route of C16H22O11 This article mentions the following:

The selective isolation of bacteria from mixed populations has been investigated in varied applications ranging from differential pathogen identification in medical diagnostics and food safety to the monitoring of microbial stress dynamics in industrial bioreactors. Selective isolation techniques are generally limited to the confinement of small populations in defined locations, may be unable to target specific bacteria, or rely on immunomagnetic separation, which is not universally applicable. In this proof-of-concept work, we describe a novel strategy combining inducible bacterial lectin expression with magnetic glyconanoparticles (MGNPs) as a platform technol. to enable selective bacterial isolation from cocultures. An inducible mutant of the type 1 fimbriae, displaying the mannose-specific lectin FimH, was constructed in Escherichia coli allowing for “on-demand” glycan-binding protein presentation following external chem. stimulation. Binding to glycopolymers was only observed upon fimbrial induction and was specific for mannosylated materials. A library of MGNPs was produced via the grafting of well-defined catechol-terminal glycopolymers prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization to magnetic nanoparticles. Thermal anal. revealed high functionalization (â‰?5% polymer by weight). Delivery of MGNPs to cocultures of fluorescently labeled bacteria followed by magnetic extraction resulted in efficient depletion of type 1 fimbriated target cells from wild-type or afimbriate E. coli. Extraction efficiency was found to be dependent on the mol. weight of the glycopolymers utilized to engineer the nanoparticles, with MGNPs decorated with shorter Dopa-(ManAA)₅₀ mannosylated glycopolymers found to perform better than those assembled from a longer Dopa-(ManAA)₂₀₀ analog. The extraction efficiency of fimbriated E. coli was also improved when the counterpart strain did not harbor the genetic apparatus for the expression of the type 1 fimbriae. Overall, this work suggests that the modulation of the genetic apparatus encoding bacterial surface-associated lectins coupled with capture through MGNPs could be a versatile tool for the extraction of bacteria from mixed populations. 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: 4163-60-4Synthetic Route of C16H22O11).

(2S,3R,4S,5S,6R)-6-(Acetoxymethyl)tetrahydro-2H-pyran-2,3,4,5-tetrayl tetraacetate (cas: 4163-60-4) 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. 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.Synthetic Route of C16H22O11

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

Exploring the regional typicality of Australian Shiraz wines using untargeted metabolomics was written by Li, S.;Blackman, J. W.;Schmidtke, L. M.. And the article was included in Australian Journal of Grape and Wine Research in 2021.COA of Formula: C9H10O3 This article mentions the following:

Shiraz is the most widely planted winegrape cultivar in Australia. Sensory studies have indicated that different grapegrowing regions in Australia produce distinct styles of Shiraz wines that differ in flavor characteristics. The current project aimed to characterize the underlying volatile composition associated with regional Shiraz wine styles. Wines were selected from six geog. distinct regions and the volatile compounds were analyzed using gas chromatog. time-of-flight mass spectrometry to provide a comprehensive and holistic overview of the wine volatilome. A suite of R language based software enabled feature extraction and importance ranking, following an untargeted metabolomics approach. A classification model based on the random forests algorithm using the 80 most important compounds correctly associated all samples to regions. A range of these compounds, including terpenoids, benzenoids, esters, furan derivatives and aliphatic alcs., has been associated with grape composition, winemaking influences and the ageing process. The results suggest that the regional compositional differences in varietal wines may be influenced by all processes in the entire wine production chain. The current study highlighted the chem. basis underlying the regional typicality of Australian Shiraz wines, and identified specific volatile compounds that may be associated with a region. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxybenzoate (cas: 118-61-6COA of Formula: C9H10O3).

Ethyl 2-hydroxybenzoate (cas: 118-61-6) 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. 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.COA of Formula: C9H10O3

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

Visible-Light-Promoted Carbene Insertion and Decarbonylation for the Synthesis of α-Substituted γ-Ketoesters was written by Li, Weina;Yang, Yingying;Tang, Zhiliang;Yu, Xianglin;Lin, Jun;Jin, Yi. And the article was included in Journal of Organic Chemistry in 2022.Related Products of 584-74-7 This article mentions the following:

Herein, a blue visible-light-promoted approach to prepare a variety of α-substituted γ-ketoesters derivatives RC(O)CH₂C(COOR¹)R²R³ [R = Ph, 3-FC₆H₄, 4-MeC₆H₄, etc.; R¹ = Me, Et; R² = H, CHO; R³ = Ph, 4-ClC₆H₄, 3-thienyl, etc.] through carbene insertion and the decarbonylation of enaminones and diazoesters was reported. These reactions used readily available starting materials, as well as transition-metal-free, eco-friendly procedures that were amenable to gram-scale synthesis and wide functional group tolerance. This methodol. might be useful for constructing polysubstituted heterocycles with potential biol. activity. In the experiment, the researchers used many compounds, for example, Ethyl 2-fluorophenylacetate (cas: 584-74-7Related Products of 584-74-7).

Ethyl 2-fluorophenylacetate (cas: 584-74-7) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. 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.Related Products of 584-74-7

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

Synthesis of Heterobiaryl 4-Aryl Furans through a Base-Promoted Decarboxylative Propargylation/Cycloisomerization Annulation was written by Wang, Sasa;Song, Meimei;Li, Xiuguang;Huang, Yunhong;Zhao, Tingxiang;Wei, Zhuoji;Lan, Yanyun;Tan, Haibo. And the article was included in Organic Letters in 2020.Reference of 13669-10-8 This article mentions the following:

A transition-metal-free synthesis of heterobiaryl 4-aryl furans through a base-promoted decarboxylative propargylation/cycloisomerization annulation of ethynyl benzoxazinanones and readily accessible β-keto esters or 1,3-diketones has been developed. A series of novel heterobiaryl 4-aryl furans were accessed efficiently in the presence of base under mild reaction conditions. This protocol is significant for probing the reaction mechanism of ethynyl benzoxazinanones and even other propargylic compounds In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Reference of 13669-10-8).

Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8) 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. 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.Reference of 13669-10-8

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