Tag: 100-200

Identification of key aroma-active compounds in beef tallow varieties using flash GC electronic nose and GC x GC-TOF/MS was written by Wang, Jing;Chen, Le;Liu, Ying;Olajide, Tosin Michael;Jiang, Yuanrong;Cao, Wenming. And the article was included in European Food Research and Technology in 2022.Application In Synthesis of 5-Ethyldihydrofuran-2(3H)-one This article mentions the following:

To uncover the integral flavor characteristics and individual odor active compounds in tallow derived from different beef fats: inguinal (IF), omental (OF), and perirenal fats (PF), we used flash GC electronic nose (flash GC E-nose) to analyze and characterize the samples. GC x GC-TOF/MS identified and quantified 195 volatile compounds with significant differences amongst the three kinds of fats. There were 45 important odorants (ROAV > 0.1) containing 23 key odorants (ROAV > 1), of which 43, 34, 35 important odorants were found in IF, OF, and PF, resp. Our results showed that the key odorants overall probably contribute to a fatty and sweat acid smell in IF, a meaty and slightly sweet taste in OF, and sweetness and slightly meaty taste in PF. Elucidating the distribution of key odorants in beef tallow from different parts of animals could provide a scientific basis for formulating and selecting raw materials of high-quality beef tallow flavor products. In the experiment, the researchers used many compounds, for example, 5-Ethyldihydrofuran-2(3H)-one (cas: 695-06-7Application In Synthesis of 5-Ethyldihydrofuran-2(3H)-one).

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, including apples, durians, pears, bananas, pineapples, and strawberries. 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.Application In Synthesis of 5-Ethyldihydrofuran-2(3H)-one

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

Preparation of some isothiocyanates was written by Cherbuliez, Emile;Weber, G.;Wyss, G.;Rabinowitz, J.. And the article was included in Helvetica Chimica Acta in 1965.Quality Control of 4-Fluorobenzylisothiocyanate This article mentions the following:

Isothiocyanates were prepared from amines and thiophosgene or by isomerization of benzyl thiocyanates. m-Trifluoromethylbenzonitrile and LiAlH₄ in ether gave 73% m-trifluoromethylbenzylamine, b₄₀ 95-7°. Vigorously stirred CSCl₂ in water treated with approx. an equimolar amount of RNH₂ yielded the following RNCS (R, b.p., and % yield listed): m-F₃CC₆H₄, b₁₂ 86-8°, 68; m-Fe₃CC₆H₄CH₂, b₈ 112-16°, 18; p-FC₆H₄(CH₂)₂, b₁₂ 135-9°, 27; p-O₂NC₆H₄, -, 85; p-BrC₆H₄, -, 71; PhCH₂, -, 60. p-Fluorobenzyl chloride and KSCN in Me₂NCHO or Me₂CO heated 4 hrs. at 40-60° gave 91% p-fluorobenzyl thiocyanate, b₁₂ 132-3°, which, heated 2 hrs. at 200°, yielded 70% p-fluorobenzyl isothiocyanate, b₉ 122-4°. p-Bromobenzyl bromide similarly gave 84% p-bromobenzyl thiocyanate, b₁₂ 172-5°, and 70% p-bromobenzyl isothiocyanate, b₉ 158-9°. 2-(p-Fluorophenyl)ethyl thiocyanate, b₁₂ 149-51°, obtained in 77% yield from the bromide, was not isomerized under these conditions. In the experiment, the researchers used many compounds, for example, 4-Fluorobenzylisothiocyanate (cas: 2740-88-7Quality Control of 4-Fluorobenzylisothiocyanate).

4-Fluorobenzylisothiocyanate (cas: 2740-88-7) 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. 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 4-Fluorobenzylisothiocyanate

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

Resonance effect in Hammett relation. IV. Linear free energy based on the normal substituent constants was written by Yukawa, Yasuhide;Tsuno, Yuho;Sawada, Masami. And the article was included in Bulletin of the Chemical Society of Japan in 1966.Recommanded Product: 587-88-2 This article mentions the following:

A set of normal substituent constants, σ0, was derived from the rates of alk. hydrolysis of m- and p-substituted Et phenylacetates in 60% Me2CO at 25.0°. The values of the σ0 constants obtained were generally identical with Taft’s values within exptl. uncertainty. On the basis of the derived σ0, substituent effects on the general electrophilic reactions were related excellently by the equation log k/k0 = ρ(σ0 + rΔ σR+), where ΔσR+ corresponds to the exaltation of Brown and Okamoto’s σ+ from σ0 (CA 53, 9120f). Similar treatment could also be applied to the nucleophilic reactions. The utility of this equation for the estimation of resonance contribution and for the consideration of reaction mechanisms is discussed. In the experiment, the researchers used many compounds, for example, Ethyl 2-(4-fluorophenyl)acetate (cas: 587-88-2Recommanded Product: 587-88-2).

Ethyl 2-(4-fluorophenyl)acetate (cas: 587-88-2) 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. 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.Recommanded Product: 587-88-2

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

Exploring the potential of wine industry by-products as source of additives to improve the quality of aquafeed was written by Camara, Jose S.;Lourenco, Silvia;Silva, Catarina;Lopes, Andre;Andrade, Carlos;Perestrelo, Rosa. And the article was included in Microchemical Journal in 2020.Electric Literature of C6H10O2 This article mentions the following:

The recent growing concern driven by consumer interest in the safety and quality of seafood, has boosted the search for healthy and functional aquafeeds. The current study represents the first approach to assess the potential of volatile composition of the wine industry by products (e.g., grape pomace, grape stems, lees), as additives for improving the quality of fish feeds in terms of organoleptic characteristics (e.g., aroma and flavor) and health benefits. Headspace solid-phase microextraction followed by gas chromatog.-mass spectrometry (HS-SPME/GC-MS) was used to establish the volatile profile of wine industry byproducts. A total of 153 volatile organic compounds (VOCs), which belong to different chem. families, comprising 36 esters, 31 carbonyl compound, 20 alcs., 18 terpenoids, 17 acids, 11 furanic compounds, four volatile phenols, two lactones, and 14 miscellaneous, were identified. Esters and terpenoids showed a pos. contribution to the aquafeeds aroma with fruity, sweet, green, fresh, and berry notes, whereas some acids (e.g., hexanoic acid) and terpenoids (e.g., limonene) could be used as antimicrobial, antioxidant and antiproliferative agents. Our findings confirmed the potential of wine industry byproducts as a rich source of essential compounds to enhance the quality of aquafeeds towards the valorization of winery waste based on the concept of circular economy. Further investigation on the extraction, isolation and purification of VOCs from a natural bio-source will guarantee the safety of the aquafeed and compliance with the requirements of the animal feed industry. In the experiment, the researchers used many compounds, for example, 5-Ethyldihydrofuran-2(3H)-one (cas: 695-06-7Electric Literature of C6H10O2).

5-Ethyldihydrofuran-2(3H)-one (cas: 695-06-7) 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.Electric Literature of C6H10O2

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

Erbium-Catalyzed Regioselective Isomerization-Cobalt-Catalyzed Transfer Hydrogenation Sequence for the Synthesis of Anti-Markovnikov Alcohols from Epoxides under Mild Conditions was written by Liu, Xin;Longwitz, Lars;Spiegelberg, Brian;Toenjes, Jan;Beweries, Torsten;Werner, Thomas. And the article was included in ACS Catalysis in 2020.Synthetic Route of C11H14O3 This article mentions the following:

Herein, we report an efficient isomerization-transfer hydrogenation reaction sequence based on a cobalt pincer catalyst (1 mol%), which allows the synthesis of a series of anti-Markovnikov alcs. from terminal and internal epoxides under mild reaction conditions (≤55°, 8 h) at low catalyst loading. The reaction proceeds by Lewis acid (3 mol % Er(OTf)₃)-catalyzed epoxide isomerization and subsequent cobalt-catalyzed transfer hydrogenation using ammonia borane as the hydrogen source. The general applicability of this methodol. is highlighted by the synthesis of 43 alcs. from epoxides. A variety of terminal (23 examples) and 1,2-disubstituted internal epoxides (14 examples) bearing different functional groups are converted to the desired anti-Markovnikov alcs. in excellent selectivity and yields of up to 98%. For selected examples, it is shown that the reaction can be performed on a preparative scale up to 50 mmol. Notably, the isomerization step proceeds via the most stable carbocation. Thus, the regiochem. is controlled by stereoelectronic effects. As a result, in some cases, rearrangement of the carbon framework is observed when tri- and tetra-substituted epoxides (6 examples) are converted. A variety of functional groups are tolerated under the reaction conditions even though aldehydes and ketones are also reduced to the resp. alcs. under the reaction conditions. Mechanistic studies and control experiments were used to investigate the role of the Lewis acid in the reaction. Besides acting as the catalyst for the epoxide isomerization, the Lewis acid was found to facilitate the dehydrogenation of the hydrogen donor, which enhances the rate of the transfer hydrogenation step. These experiments addnl. indicate the direct transfer of hydrogen from the amine borane in the reduction step. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0Synthetic Route of C11H14O3).

Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0) 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.Synthetic Route of C11H14O3

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

Electrochemical Synthesis of 1-Naphthols by Intermolecular Annulation of Alkynes with 1,3-Dicarbonyl Compounds was written by He, Mu-Xue;Mo, Zu-Yu;Wang, Zi-Qiang;Cheng, Shi-Yan;Xie, Ren-Ren;Tang, Hai-Tao;Pan, Ying-Ming. And the article was included in Organic Letters in 2020.Safety of Ethyl 3-oxo-3-(thiophen-2-yl)propanoate This article mentions the following:

C-centered radical cyclization under electrochem. conditions is a feasible strategy for constructing cyclic structures. Reported herein is the electrochem. synthesis of highly functionalized 1-naphthols using alkynes and 1,3-dicarbonyl compounds by (4 + 2) annulation of C-centered radical. Electrolysis was conducted with Cp₂Fe as redox catalyst, thereby eliminating the use of oxidants and transition-metal catalysts. The synthesized 1-naphthol compounds showed good antitumor activity in vitro, and further studies indicated that compound I induced tumor cell apoptosis. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8Safety of Ethyl 3-oxo-3-(thiophen-2-yl)propanoate).

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

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

Stereoselective Synthesis of Vinylboronates by Rh-Catalyzed Borylation of Stereoisomeric Mixtures was written by Li, Shenhuan;Li, Jie;Xia, Tianlai;Zhao, Wanxiang. And the article was included in Chinese Journal of Chemistry in 2019.Reference of 19432-68-9 This article mentions the following:

The stereoselective preparation of vinylboronates via rhodium-catalyzed borylation of E/Z mixtures of vinyl acetates is described, and this method was also extended to synthesis of vinyldiboronates. These transformations feature high functional group compatibility and mild reaction conditions. Control experiments support a mechanism that involved a Rh-catalyzed borylation-isomerization sequence. The isomerization of (Z)-vinylboronates to (E)-isomers was also demonstrated. In the experiment, the researchers used many compounds, for example, Methyl 2-thienylacetate (cas: 19432-68-9Reference of 19432-68-9).

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. 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.Reference of 19432-68-9

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

Effect of microbial communities on the quality characteristics of northeast soybean paste: Correlation between microorganisms and metabolites was written by Yao, Di;Ma, Lixue;Wu, Mengna;Wang, Xiaoyu;Xu, Lei;Yu, Qiaoru;Wang, Changyuan. And the article was included in LWT–Food Science and Technology in 2022.Category: esters-buliding-blocks This article mentions the following:

To systematically explore the impact of microbial community composition on the quality characteristics of northeast soybean paste, the microbial community structure was determined by high-throughput sequencing technol. and the flavor substance, free amino acid (FAA) and biogenic amine (BA) contents were determined by HS-SPME-GC-MS and HPLC. Furthermore, the correlation between microorganisms and metabolites was investigated. The results indicated that the core bacteria mainly included Tetragenococcus, Bacillus and Lactobacillus; Candida_f__norank, Wickerhamomyces and Aspergillus were the dominant fungi. A total of 139 flavor compounds were detected in all samples, and decamethylcyclopentasiloxane, isoamyl phenylacetate and octamethylcyclotetrasiloxane accounted for the highest proportion. A total of 24 FAAs were detected in the soybean paste. Pantoea, Kroppenstedtia and Kocuria were significantly pos. correlated with most FAAs (p < 0.05). Addnl. 5 BAs were detected in the soybean paste, and the contents of BAs in Y4 were highest, which was affected by different microbes. This study provided relevant information for the microbial community composition and metabolites of northeast soybean paste, which was of great significance for understanding the characteristics and safety of soybean paste. In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Category: esters-buliding-blocks).

5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9) 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. 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.Category: esters-buliding-blocks

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

Changes of Sensory Quality, Flavor-Related Metabolites and Gene Expression in Peach Fruit Treated by Controlled Atmosphere (CA) under Cold Storage was written by Liu, Hongru;He, Hui;Liu, Chenxia;Wang, Chunfang;Qiao, Yongjin;Zhang, Bo. And the article was included in International Journal of Molecular Sciences in 2022.COA of Formula: C10H18O2 This article mentions the following:

Controlled atm. (CA) has been used to alleviate chilling injury (CI) of horticultural crops caused by cold storage. However, the effects of CA treatment on peach fruit sensory quality and flavor-related chems. suffering from CI remain largely unknown. Here, we stored peach fruit under CA with 5% O₂ and 10% CO₂ at 0°C up to 28 d followed by a subsequent 3 d shelf-life at 20°C (28S3). CA significantly reduced flesh browning and improved sensory quality at 28S3. Though total volatiles declined during extended cold storage, CA accumulated higher content of volatile esters and lactones than control at 28S3. A total of 14 volatiles were pos. correlated with consumer acceptability, mainly including three C6 compounds, three esters and four lactones derived from the fatty acid lipoxygenase (LOX) pathway. Correspondingly, the expression levels of genes including PpLOX1, hyperoxide lyase PpHPL1 and alc. acyltransferase PpAAT1 were pos. correlated with the change of esters and lactones. CA elevated the sucrose content and the degree of fatty acids unsaturation under cold storage, which gave us clues to clarify the mechanism of resistance to cold stress. The results suggested that CA treatment improved sensory quality by alleviating CI of peach fruits under cold storage. In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9COA of Formula: C10H18O2).

5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9) 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. 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: C10H18O2

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

Cooperative Catalysis for the Highly Diastereo- and Enantioselective [4+3]-Cycloannulation of ortho-Quinone Methides and Carbonyl Ylides was written by Suneja, Arun;Loui, Henning Jakob;Schneider, Christoph. And the article was included in Angewandte Chemie, International Edition in 2020.SDS of cas: 13669-10-8 This article mentions the following:

Herein a highly diastereo- and enantioselective [4+3]-cycloannulation of ortho-quinone methides and carbonyl ylides to furnish functionalized oxa-bridged dibenzooxacines with excellent yields and stereoselectivity in a single synthetic step is described. The combination of rhodium and chiral phosphoric acid catalysis working in concert to generate both transient intermediates in situ provides direct access to complex bicyclic products with two quaternary and one tertiary stereogenic centers. The products may be further functionalized into valuable and enantiomerically highly enriched building blocks. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(thiophen-2-yl)propanoate (cas: 13669-10-8SDS of cas: 13669-10-8).

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

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