Month: February 2023

Oxidative rearrangement of alkynes to carboxylic acid esters by [hydroxy(tosyloxy)iodo]benzene in methanol was written by Moriarty, Robert M.;Vaid, Radhe K.;Duncan, Michael P.;Vaid, Beena K.. And the article was included in Tetrahedron Letters in 1987.Safety of Methyl 2-thienylacetate This article mentions the following:

RR¹CHCO₂Me (I; R = Pr, Bu, Ph, C₆H₄Ac-4, thienyl; R¹ = H, Me, Et) were prepared by oxidative rearrangement of RCCR¹ with [hydroxy(tosyloxy)iodo]benzene in MeOH. Hydrolysis of I gave RR¹CHCO₂H. In the experiment, the researchers used many compounds, for example, Methyl 2-thienylacetate (cas: 19432-68-9Safety of Methyl 2-thienylacetate).

Methyl 2-thienylacetate (cas: 19432-68-9) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. 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 Methyl 2-thienylacetate

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

Improved synthesis of 3-methylpyrrole was written by Lancaster, Roscoe E. Jr.;VanderWerf, Calvin A.. And the article was included in Journal of Organic Chemistry in 1958.Name: Ethyl 4-methyl-1H-pyrrole-3-carboxylate This article mentions the following:

Pure 3-methylpyrrole (I) was synthesized in 37.8% yield starting with K phthalimide (II) by condensation of aminoacetone (III) with di-Et oxalacetate (IV) and subsequent hydrolysis and decarboxylation of the product, 2-carboxy-3-carbethoxy-4-methylpyrrole (V). The chief improvement is the method for in situ synthesis of III and in the improvement of the subsequent steps as well as the more complete characterization of I. II (250 g.) with 200 g. ClCH₂Ac heated gently until reaction started, the reaction allowed to go to completion at room temperature, and the product isolated gave 269 g. N-acetonylphthalimide (VI), m. 116.0-16.8° (H₂O). Concentrated HCl (150 ml.) and 75 ml. H₂O refluxed 4 hrs. with 50 g. crude VI, cooled, the pH brought to 1.5, the filtrate slowly added to 45 g. IV Na salt in 400 ml. H₂O while the temperature was maintained at 75° and the pH at 5 with small additions of NaOH solution, the mixture cooled, the precipitate removed, the pH of the filtrate adjusted to 8, the solution heated 0.5 hr. at 75°, reacidified, and separated gave 25.5 g. V, m. 195.7-6.8°. V (67 g.) refluxed 24 hrs. with 440 g. KOH in 1250 ml. H₂O, the pH adjusted to 9, cooled, and collected gave after acidification of the filtrate 42.5 g. 3-carbethoxy-4-methylpyrrole (VII), m. 152.6-3.7°. VII (22 g.) on dry distillation gave 10.6 g. I, b₇₄₀ 142-3°, n²⁰_D 1.4970, n²⁵_D 1.4949. The absorption bands in the infrared spectra of I and 2-methylpyrrole (II) were compared in a table and the infrared spectra of 12.25% solutions of I and II in CHCl₃ taken and the curves shown in figures. In the experiment, the researchers used many compounds, for example, Ethyl 4-methyl-1H-pyrrole-3-carboxylate (cas: 2199-49-7Name: Ethyl 4-methyl-1H-pyrrole-3-carboxylate).

Ethyl 4-methyl-1H-pyrrole-3-carboxylate (cas: 2199-49-7) 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.Name: Ethyl 4-methyl-1H-pyrrole-3-carboxylate

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

A high-throughput HPLC method for simultaneous quantification of pyrethroid and pyriproxyfen in long-lasting insecticide-treated nets was written by Walker, Kyle J.;Williams, Christopher T.;Oladepo, Folasade O.;Lucas, John;Malone, David;Paine, Mark J. I.;Ismail, Hanafy M.. And the article was included in Scientific Reports in 2022.COA of Formula: C20H26O4 This article mentions the following:

Long-lasting insecticide-treated nets (LLINs) play a crucial role in preventing malaria transmission. LLINs should remain effective for at least three years, even after repeated washings. Currently, monitoring insecticides in LLINs is cumbersome, costly, and requires specialized equipment and hazardous solvents. Our aim was to develop a simple, high-throughput and low-resource method for measuring insecticides in LLINs. To extract insecticides, polyethylene-LLIN samples were heated at 85 °C for 45 min in a non-hazardous solvent mix containing dicyclohexylphthalate as an internal standard The extraction solvent was reduced from 50 to 5 mL using a 0.2 g sample, 90% smaller than the recommended sample size. By optimizing HPLC chromatog., we simultaneously detected pyrethroid and pyriproxyfen insecticides with high sensitivity in LLIN′s extract The method can quantify levels â‰?0.0015% permethrin, 0.00045% alpha-cypermethrin and 0.00025% pyriproxyfen (weight/weight) in polyethylene, allowing for insecticide tracking before and after the use of LLINs. This method can be used to assess LLINs with 1% pyriproxyfen (pyriproxyfen-LLIN) or 2% permethrin (Olyzet Net), 1% pyriproxyfen and 2% permethrin (Olyzet Duo), or 0.55% pyriproxyfen and 0.55% alpha-cypermethrin (Royal Gaurd). One can run 120 samples (40 nets) simultaneously with high precision and accuracy, improving throughput and reducing labour, costs, and environmental impact. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7COA of Formula: C20H26O4).

Dicyclohexyl phthalate (cas: 84-61-7) 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. 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.COA of Formula: C20H26O4

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

Sour beer production in India using a coculture of Saccharomyces pastorianus and Lactobacillus plantarum: optimization, microbiological, and biochemical profiling was written by Mahanta, Sachin;Sivakumar, P. S.;Parhi, Pankaj;Mohapatra, Ranjan K.;Dey, Gargi;Panda, Smita H.;Sireswar, Srijita;Panda, Sandeep K.. And the article was included in Brazilian Journal of Microbiology in 2022.Recommanded Product: 5-Hexyldihydrofuran-2(3H)-one This article mentions the following:

The study’s objective was to develop a co-fermentation process with appropriate fermentation parameters to produce a sour beer (similar to a Belgium sour beer) with an ethanol content of 6-8% (volume/volume) using a coculture of Saccharomyces pastorianus and Lactobacillus plantarum. Statistical optimization was conducted to determine fermentation conditions to produce a sour beer with âˆ?3 mg/mL of lactic acid, similar to the traditional sour beer levels. Studies were conducted on the microbial dynamics and volatile compounds produced during this fermentation and aging process. GC-MS studies revealed the generation of novel bioactive compounds as well as the depletion of some volatile compounds during co-fermentation The study detailed a 5-day co-fermentation process of S. pastorianus and L. plantarum and a 21-day aging process to prepare a sour beer with biochem. properties along the lines of traditional lambic beers. The interrelationship between the two microorganisms and the biochem. changes in the sour beer fermentation process was elucidated and the sensorial attributes have been described. In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Recommanded Product: 5-Hexyldihydrofuran-2(3H)-one).

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

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

Exploring in vitro to in vivo extrapolation for exposure and health impacts of e-cigarette flavor mixtures was written by Chang, Xiaoqing;Abedini, Jaleh;Bell, Shannon;Lee, K. Monica. And the article was included in Toxicology In Vitro in 2021.Synthetic Route of C10H18O2 This article mentions the following:

In vitro to in vivo extrapolation (IVIVE) leverages in vitro biol. activities to predict corresponding in vivo exposures, therefore potentially reducing the need for animal safety testing that are traditionally performed to support the hazard and risk assessment. Interpretation of IVIVE predictions are affected by various factors including the model type, exposure route and kinetic assumptions for the test article, and choice of in vitro assay(s) that are relevant to clin. outcomes. Exposure scenarios are further complicated for mixtures where the in vitro activity may stem from one or more components in the mixture In this study, we used electronic cigarette (EC) aerosols, a complex mixture, to explore impacts of these factors on the use of IVIVE in hazard identification, using open-source pharmacokinetic models of varying complexity and publicly available data. Results suggest in vitro assay selection has a greater impact on exposure estimates than modeling approaches. Using cytotoxicity assays, high exposure estimates (>1000 EC cartridges (pods) or > 700 mL EC liquid per day) would be needed to obtain the in vivo plasma levels that are corresponding to in vitro assay data, suggesting acute toxicity would be unlikely in typical usage scenarios. When mechanistic (Tox21) assays were used, the exposure estimates were much lower for the low end, but the range of exposure estimate became wider across modeling approaches. These proof-of-concept results highlight challenges and complexities in IVIVE for mixtures In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Synthetic Route of C10H18O2).

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

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

High-throughput screening of 756 chemical contaminants in aquaculture products using liquid chromatography/quadrupole time-of-flight mass spectrometry was written by Bai, Mingkai;Tang, Ruixue;Li, Guorong;She, Wenhai;Chen, Gangjun;Shen, Hongmei;Zhu, Suqin;Zhang, Hongwei;Wu, Haohao. And the article was included in Food Chemistry: X in 2022.Reference of 84-61-7 This article mentions the following:

A high-throughput screening method embracing 756 multiclass chem. contaminants in aquaculture products was developed using modified QuEChERS extraction coupled with liquid chromatog./quadrupole time-of-flight mass spectrometry. A mega-database with retention time/accurate mass data for 524 pesticides, 182 veterinary drugs, 32 persistent organic pollutants and 18 marine toxins was established for compound identification via retrospective library searching. In the four representative matrixes (muscle tissues of tilapia and grouper, and edible portions of oyster and scallop), all the database compounds showed acceptable recovery and repeatability with the screening detection limit and limit of quantification below 0.01 mg/kg for >90% of them. The matrix-matched calibration revealed acceptable quant. property of the method in terms of linear range, linearity, and matrix effect, and fish muscle samples showed stronger matrix effect than shellfish samples. Anal. of 64 real-life samples from aquaculture farms and retail markets evidenced applicability of the proposed method to high-throughput screening scenarios. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Reference of 84-61-7).

Dicyclohexyl phthalate (cas: 84-61-7) 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. 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.Reference of 84-61-7

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

Synthesis and characterization of tin oxide-modified mesoporous SBA-15 molecular sieves and catalytic activity in trans-esterification reaction was written by Shah, Pallavi;Ramaswamy, Arumugamangalam V.;Lazar, Karoly;Ramaswamy, Veda. And the article was included in Applied Catalysis, A: General in 2004.Reference of 1190-39-2 This article mentions the following:

Mesoporous silica mol. sieve SBA-15 has been synthesized and incorporated with various amounts of tin via incipient-wetness impregnation using tin chloride in ethanol followed by calcination. Characterization was done by x-ray fluorescence spectrophotometry (XRF), powder x-ray diffraction (PXRD), nitrogen adsorption, diffuse reflectance UV (DRUV), scanning and transmission electron microscopy (SEM, TEM), FTIR, ²⁹Si and ¹¹⁹Sn MAS NMR, and Sn-Moessbauer spectroscopic techniques to understand the chem. nature of incorporated tin. The silanol groups on the internal walls of SBA-15 are suggested to be the sites for tin incorporation. Bulk structural characterization techniques (x-ray diffraction and BET) are used to demonstrate that the hexagonal structure is maintained during impregnation. Tin oxide exists as a thin film anchored inside the mesopores of SBA-15. Complementarily, ¹¹⁹Sn NMR and Moessbauer spectroscopies are used to investigate the microstructure of the Sn centers grafted to the mesoporous walls. Sn-Moessbauer spectroscopic studies reveal that Sn²⁺ may form upon reductive treatments and can probably be stabilized atomically in the pore wall, whereas Sn⁴⁺ is stabilized as large entities. While SBA-15 itself shows some activity in transesterification of di-Et malonate with various alcs., Sn-SBA-15 samples are found to possess enhanced catalytic activity for the same. In the experiment, the researchers used many compounds, for example, malonic acid dibutyl ester (cas: 1190-39-2Reference of 1190-39-2).

malonic acid dibutyl ester (cas: 1190-39-2) 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.Reference of 1190-39-2

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

Anti-inflammatory effect of essential oil from Amomum Tsaoko Crevost et Lemarie was written by Liao, Liangkun;Yang, Shengtao;Li, Ruyi;Zhou, Wei;Xiao, Yu;Yuan, Yuan;Cha, Yunsheng;He, Guifang;Li, Jihua. And the article was included in Journal of Functional Foods in 2022.SDS of cas: 105-87-3 This article mentions the following:

Amomum Tsaoko Crevost et Lemarie is a kind of spices and traditional Chinese medicines with great com. value. Traditional treatment often uses essential oils from Amomum Tsaoko in aromatherapy. In this study, researchers analyzed the composition of steam-distilled essential oil from Amomum tsaoko (ATEO) and evaluated its potential antioxidant and anti-inflammatory activity. GC-MS identified a total of 33 volatile compounds, the majority of which were alc. (1,8-cineole and nerol) and aldehyde ((2E)-2-decenal) compounds Addnl., ATEO showed great anti-inflammatory activity in LPS-induced RAW 264.7 macrophages. ATEO markedly inhibited the nitric oxide (NO) release, and decreased the expression level of TNF-α, IL-1β, IL-6 and monocyte chemotactic protein-1 (MCP-1) in a dose-dependent manner. Furthermore, ATEO significantly reduced the expression of iNOS, COX-2, NF-κB p-p65 and p-ERK. These results suggested that ATEO has great anti-inflammatory activity in LPS-induced RAW 264.7 cells, which will facilitate the development of ATEO as a functional food. In the experiment, the researchers used many compounds, for example, (E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3SDS of cas: 105-87-3).

(E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. 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.SDS of cas: 105-87-3

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

Producing beef flavors in hydrolyzed soybean meal-based Maillard reaction products participated with beef tallow hydrolysates was written by Ye, Yongkang;Ye, Shuangshuang;Wanyan, Zhangxiang;Ping, Hao;Xu, Zixun;He, Shudong;Cao, Xiaodong;Chen, Xiangyang;Hu, Wanwan;Wei, Zhaojun. And the article was included in Food Chemistry in 2022.Electric Literature of C10H18O2 This article mentions the following:

This work investigated the effect of oxidized beef tallow on the volatile compositions and sensory properties of soybean meal-based Maillard reaction products (MRPs). Various tallow oxidation methods included thermal treatment (TT), enzymic hydrolysis (ET) and enzymic hydrolysis combined with mild thermal (ETT) treatment. Results showed that all these oxidized tallow contained more types of volatile compounds than those of untreated tallow. Moreover, the composition of almost all types of volatile substances was greatly increased with the addition of the oxidized beef tallow into the hydrolyzed soybean meal-based Maillard reaction system. More importantly, the composition of oxygen-containing heterocycles (63.89 μg/mL), sulfur-containing compounds (76.64 μg/mL), and nitrogen-containing heterocycles (19.81 μg/mL) that contribute pos. to sensory properties in ETT-MRPs was found to be the highest among all the MRPs. Correlation assessment revealed that ETT was closely related to the most typical volatile products and sensory attributes, indicating this approach can effectively enhance the sensory and flavor of hydrolyzed soybean meal derived MRPs. In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Electric Literature of C10H18O2).

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

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

Synthesis of New C-2 Triazole-Linked Analogs of Triterpenoid Pentacyclic Saponins was written by Spivak, A. Yu.;Galimshina, Z. R.;Nedopekina, D. A.;Odinokov, V. N.. And the article was included in Chemistry of Natural Compounds in 2018.Related Products of 4163-60-4 This article mentions the following:

C-2 mono- and bis-1,2,3-triazole-linked analogs, e.g., I, of lupane, ursane, and oleane triterpenoid saponins were synthesized for the first time using regioselective Cu(I)-catalyzed 1,3-dipolar cycloaddition (CuAAC) of peracetylated sugar azides and C-2 propynyl derivatives of triterpene acids. Cytotoxic activity of the synthesized compounds was studied in vitro at the National Cancer Institute (USA). Several of the synthesized compounds exhibited weak cytotoxic activity. 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: 4163-60-4Related Products of 4163-60-4).

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

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