Tag: 100-200

Chemicals tested as space repellents against yellow-fever mosquitoes. I. Esters was written by Gouck, Harry K.;McGovern, Terence P.;Beroza, Morton. And the article was included in Journal of Economic Entomology in 1967.Reference of 15399-05-0 This article mentions the following:

A total of 242 esters were tested for effectiveness as space repellents by applying them to netting with openings large enough to allow yellow-fever mosquitoes, Aedes aegypti, to pass through, and determining the number of days the netting prevented passage of >10% of the mosquitoes to a human arm. The 5 compounds that were effective >100 days were: dipentyl, diisopentyl, and bis(1-methylbutyl) malate, hexyl p-isopropylmandelate, and bis(2-ethylhexyl) fumarate. Esters with a hydroxyl group appeared to be more effective than those without this group. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0Reference of 15399-05-0).

Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0) 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.Reference of 15399-05-0

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

Effect of different cooking methods on flavor compounds of Chinese traditional condiment Wuxiang powder was written by Bi, Jicai;Li, Yang;Lin, Zeyuan;Yang, Zhen;Chen, Fusheng;Liu, Sixin;Li, Congfa. And the article was included in Journal of Food Processing and Preservation in 2022.Formula: C12H20O2 This article mentions the following:

The Wuxiang powder is a Chinese traditional condiment with a strong aroma and flavor. Moreover, it is suitable for dishes prepared using several cooking methods. Gas chromatog.-ion mobility spectrometry was used to analyze the changes in the flavor of the original Wuxiang powder, the air-fried Wuxiang powder and the stewed Wuxiang powder. A total of 49 volatile compounds were studied, including 17 aldehydes, 9 alkenes, 9 esters, 7 alcs., 2 ethers, 2 furans, 1 acid, 1 ketone and 1 phenol. The contents of aldehydes, hydrocarbons, esters and alcs. were higher than others. The principal component anal. elucidated significant differences in the aroma among different cooking methods of the Wuxiang powder. According to the relative odor activity value, the major flavor compounds that contributed to the difference in the aroma among different cooking methods were (Z, Z)-2, 4-decadienal, anethole, decanal, 3-methylbutanal, β-caryophyllene, α-pinene, linalool, eugenol, octanal, heptanal, and hexanal. In the experiment, the researchers used many compounds, for example, (E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3Formula: C12H20O2).

(E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3) 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.Formula: C12H20O2

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

Total synthesis and absolute configuration of the antibiotic oligopeptide (4S)-(+)-anthelvencin A and its 4R-(-) enantiomer was written by Lee, Moses;Coulter, Diane M.;Lown, J. William. And the article was included in Journal of Organic Chemistry in 1988.Safety of Ethyl 4-nitro-1H-pyrrole-2-carboxylate This article mentions the following:

The total syntheses of (4S)-(+)-anthelvencin A (I) (the naturally occurring isomer) and its (4R)-(-) enantiomer are described. The absolute configuration of natural anthelvencin A is thereby unambiguously assigned. The two enantiomers bind to duplex calf thymus DNA. In the experiment, the researchers used many compounds, for example, Ethyl 4-nitro-1H-pyrrole-2-carboxylate (cas: 5930-92-7Safety of Ethyl 4-nitro-1H-pyrrole-2-carboxylate).

Ethyl 4-nitro-1H-pyrrole-2-carboxylate (cas: 5930-92-7) 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. 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.Safety of Ethyl 4-nitro-1H-pyrrole-2-carboxylate

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

Synergistic antibacterial mechanism of different essential oils and their effect on quality attributes of ready-to-eat pakchoi (Brassica campestris L. ssp. chinensis) was written by Zhang, Lihui;Zhang, Min;Ju, Ronghua;Mujumdar, Arun S.;Liu, Kun. And the article was included in International Journal of Food Microbiology in 2022.Formula: C12H20O2 This article mentions the following:

The mixture of garlic essential oil (GEO), ginger essential oil (GIEO) and litsea cubeba essential oil (LCEO) was prepared and its effect on the antibacterial activity of E. coli, S. aureus and P. aeruginosa, as well as properties of ready-to-eat pakchoi during storage were assessed. GEO, GIEO or LCEO treatment significantly enhanced the accumulation of reactive oxygen species (ROS) levels, resulting in disruption of the permeability of cell membrane, the leakage of cytoplasmic contents, and the alteration of the secondary structure of bacterial proteins. Meanwhile, GEO, GIEO or LCEO treatment repressed the key enzyme in tricarboxylic acid (TCA) and Hexose monophosphate pathway (HMP) cycle of E. coli, S. aureus and P. aeruginosa. Essential oil treatments (p < 0.05) could significantly prolong the shelf life of pakchoi, total bacterial count (TBC) values and chlorophyll content of GEO/GIEO/LCEO sample were 3.47 log cfu/g and 0.82 mg/g, resp., after storage for 7 days. E. coli, S. aureus and P. aeruginosa counts in GEO/GIEO/LCEO samples decreased by 56.76%, 70.10%, 73.95% compared to CK (no essential oil) samples. The comprehensive results from the sensory (flavor and color) and microbial anal. (especially TBC) showed that GEO/GIEO/LCEO could extend the shelf life of ready-to-eat pakchoi from 4 d to 7 d. As compared with GEO, GIEO or LCEO individually, the combination of GEO, GIEO and LCEO exhibited synergistic effect and more pronouncedly antibacterial activity to improve quality of ready-to-eat pakchoi. In the experiment, the researchers used many compounds, for example, (E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3Formula: C12H20O2).

(E)-3,7-Dimethylocta-2,6-dien-1-yl acetate (cas: 105-87-3) 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.Formula: C12H20O2

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

Synthesis and x-ray structure of stable 2H-isoindoles was written by Murashima, Takashi;Tamai, Ryuji;Nishi, Keiji;Nomura, Kentaroh;Fujita, Ken-ichi;Uno, Hidemitsu;Ono, Noboru. And the article was included in Perkin 1 in 2000.Computed Properties of C7H8N2O4 This article mentions the following:

Stable 2H-isoindoles with electron-withdrawing groups were prepared by reaction of meta-dinitrobenzenes with isocyanoacetate in the presence of DBU. The use of MeCN as the solvent or a phosphazene base (BTPP) as a non-ionic base improved the yields. The structure was confirmed by x-ray crystallog. anal. of tert-Bu 7-cyano-5-nitro-2H-isoindole-1-carboxylate. According to the x-ray anal., this substance existed in the solid phase only as the 2H-isomer. In the experiment, the researchers used many compounds, for example, Ethyl 4-nitro-1H-pyrrole-2-carboxylate (cas: 5930-92-7Computed Properties of C7H8N2O4).

Ethyl 4-nitro-1H-pyrrole-2-carboxylate (cas: 5930-92-7) 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. 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.Computed Properties of C7H8N2O4

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

1-Aryl-3-azabicyclo[3.1.0]hexanes, a new series of nonnarcotic analgesic agents was written by Epstein, Joseph W.;Brabander, Herbert J.;Fanshawe, William J.;Hofmann, Corris M.;McKenzie, Thomas C.;Safir, Sidney R.;Osterberg, Arnold C.;Cosulich, D. B.;Lovell, F. M.. And the article was included in Journal of Medicinal Chemistry in 1981.Recommanded Product: Ethyl 2-(4-fluorophenyl)acetate This article mentions the following:

The title analgesics I (R = organo substituent) were prepared by insertion reaction of RC₆H₄CHBrCO₂R with acrylate esters followed by cyclocondensation of the resultant cyclopropanedicarboxylic acid derivatives with urea, than reduction of the resultant amides. The more potent I are the para-substituted derivatives In the experiment, the researchers used many compounds, for example, Ethyl 2-(4-fluorophenyl)acetate (cas: 587-88-2Recommanded Product: Ethyl 2-(4-fluorophenyl)acetate).

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

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

Influence of Freezing and Different Drying Methods on Volatile Profiles of Strawberry and Analysis of Volatile Compounds of Strawberry Commercial Jams was written by Abouelenein, Doaa;Mustafa, Ahmed M.;Angeloni, Simone;Borsetta, Germana;Vittori, Sauro;Maggi, Filippo;Sagratini, Gianni;Caprioli, Giovanni. And the article was included in Molecules in 2021.Category: esters-buliding-blocks This article mentions the following:

Strawberry is the most consumed berry fruit worldwide due to its unique aroma and flavor. Drying fruits to produce a powder represents one of the possible conservation methods to extend their shelf-life. The aim of the present study was to compare the influence of freezing and different drying methods on the volatile profile of strawberry using the HS-SPME/GC-MS method, in addition to anal. of strawberry jam volatiles. A total of 165 compounds were identified, accounting for 85.03-96.88% of the total volatile compositions Results and PCA showed that freezing and each drying process affected the volatile profile in a different way, and the most remarkable representative differential volatiles were Et hexanoate, hexyl acetate, (E)-2-hexenyl acetate, mesifurane, (E)-nerolidol, γ-decalactone, 1-hexanol, and acetoin. Shade air-dried, frozen, freeze-dried, and oven-dried 45°C samples retained more of the fruity and sweet aromas of strawberry, representing more than 68% of the total aroma intensity according to the literature. In contrast, the microwave-drying method showed drastic loss of fruity esters. Strawberry jams demonstrated complete destruction of esters and alcs. in most jams, while terpenes were significantly increased. These findings help better understand the aroma of strawberry and provide a guide for the effects of drying, freezing, and jam processing. In the experiment, the researchers used many compounds, for example, 5-Ethyldihydrofuran-2(3H)-one (cas: 695-06-7Category: esters-buliding-blocks).

5-Ethyldihydrofuran-2(3H)-one (cas: 695-06-7) 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.Category: esters-buliding-blocks

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

Constituents of aromatic importance in Biancolella wine: an analytical study by gas chromatography/olfactometry was written by Moio, Luigi;Etievant, Patrick;Addeo, Francesco. And the article was included in Vignevini in 1993.Category: esters-buliding-blocks This article mentions the following:

Flavor components (54), such as alcs., esters, ketones, lactones, S compounds, and volatile phenols, were determined in 2 types of Biancolella wine. Some components were correlated with organoleptically-determined flavors and with the charm value (Acree, T. E., et al., 1984). In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0Category: esters-buliding-blocks).

Ethyl 2-hydroxy-3-phenylpropanoate (cas: 15399-05-0) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. 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. Category: esters-buliding-blocks

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

Pyrido[2,3-d]pyrimidines. II. Synthesis of ribonucleosides of 4-oxo- and 2,4-dioxopyrido[2,3-d]pyrimidines was written by Rizkalla, Boshra H.;Broom, Arthur D.;Stout, Mason G.;Robins, Roland K.. And the article was included in Journal of Organic Chemistry in 1972.Recommanded Product: 14667-47-1 This article mentions the following:

Synthesis of 1-β-D-ribofuranosyl-4-oxopyrido[2,3-d]pyrimidine and 1- and 8-β-D-ribofuranosyl-2,4-dioxopyrido[2,3-d]pyrimidine are described. The site of ribosylation in each case is assigned by uv and PMR comparisons with requisite N-Me model compounds The assignment of anomeric configuration is based upon PMR spectroscopy. A facile N-8 â†?N-1 ribosyl rearrangement is described. In the experiment, the researchers used many compounds, for example, Methyl 2-aminonicotinate (cas: 14667-47-1Recommanded Product: 14667-47-1).

Methyl 2-aminonicotinate (cas: 14667-47-1) 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.Recommanded Product: 14667-47-1

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

Effects of electron-beam irradiation on volatile flavor compounds of salmon fillets by the molecular sensory science technique was written by Guo, Hongxia;Feng, Tao;Qi, Wenyuan;Kong, Qiulian;Yue, Ling;Wang, Haihong. And the article was included in Journal of Food Science in 2021.Computed Properties of C10H18O2 This article mentions the following:

Vacuum-packed salmon was treated by electron beam irradiation preservation technol., to study the effects of electron-beam irradiation on odor active compounds of salmon by two types of methods for extraction: headspace-solid phase micro extraction (HS-SPME) and solvent assisted flavor evaporation (SAFE). Volatile flavor compounds examined by gas chromatog.-mass spectrometry (GC-MS) and gas chromatog.-olfactometry (GC-O), combined with aroma extract dilution method (AEDA) and odor activity value (OAV) for identification of important odorants. In addition, the correlation between sensory attributes and volatile compounds of salmon irradiated at different doses was analyzed by partial least squares regression (PLSR). The results showed that after SPME and SAFE extraction, a total of 49 and 70 volatile flavor compounds were detected in salmon before and after electron beam irradiation AEDA and OAV were further identified, among which 10 odorants were considered as important volatile flavor compounds and played an important role in the formation of aroma contours such as meaty, fatty, and grassy in salmon. In addition, methanethiol, 3-Me butyraldehyde, 3-Me Pr aldehyde, di-Me disulfide, di-Me trisulfide, and 2-pentyl furan were identified as the important volatile flavor compounds in salmon irradiated with 4 kGy, and were also the unique compounds that constituted irradiation off-odor. In general, salmon irradiated with 1 kGy showed the best aroma profile. Practical Application : SPME and SAFE were used as two types of extraction methods for volatile compounds of salmon, which complemented each other. Addnl., combined with AEDA and OAV, characteristic flavor compounds were identified. Furthermore, the odor fingerprint of salmon with E-beam irradiation was established for the first time. In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Computed Properties of C10H18O2).

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. 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 C10H18O2

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