Month: February 2023

Immobilization of the acylase from Escherichia coli on glyoxyl-agarose gives efficient catalyst for the synthesis of cephalosporins was written by Estruch, Ilona;Tagliani, Auro R.;Guisan, Jose Manuel;Fernandez-Lafuente, Roberto;Alcantara, Andres R.;Toma, Lucio;Terreni, Marco. And the article was included in Enzyme and Microbial Technology in 2008.Electric Literature of C7H8O2S This article mentions the following:

The catalytic properties of penicillin G acylase (PGA) from Escherichia coli, when used in kinetically controlled N-acylation (kcNa) of cephalosporanic nuclei, can be strongly influenced by the moiety in 3-position of the cephem structure. In the synthesis of Cefonicid (1c), the adsorption of the cephalosporanic nucleus (7-SACA) in the PGA active site appeared sensitively increased by a pos. ionic interaction between an arginine (ArgA145) in the enzyme active site and the sulfonic group of the β-lactam structure. Interestingly, when PGA was immobilized on solid supports, any effect depending on the substrate structure resulted minimized; the catalytic properties of this enzyme were affected with different outcomes depending on the type of matrix and binding chem. The PGA immobilized on glyoxyl-agarose (hydrophilic support activated with aldehyde groups) resulted in a good catalyst when used in kinetically controlled N-acylation of different cephalosporanic nuclei. This derivatives allow much better Vs/Vh₁ (defined as the ratio between the rate of synthesis and the rate of hydrolysis of the acylating agent) than the same enzyme immobilized on Eupergit C, an acrylic hydrophobic supports activated with epoxy groups. The synthetic performances of the Eupergit derivative vs. different nuclei were always much poorer if compared with glyoxyl-agarose or the soluble protein. The use of PGA immobilized on glyoxyl-agarose allowed the development of efficient processes for the preparation of Cefazolin in high yield and purity. The results obtained in the optimization of this process are presented. In the experiment, the researchers used many compounds, for example, Methyl 2-thienylacetate (cas: 19432-68-9Electric Literature of C7H8O2S).

Methyl 2-thienylacetate (cas: 19432-68-9) 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 C7H8O2S

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

Intramolecular trapping of ammonium ylides with N-benzoylbenzotriazoles in aqueous medium: direct access to the pseudoindoxyl scaffold was written by Devi, Lalita;Shukla, Rashmi;Rastogi, Namrata. And the article was included in Organic & Biomolecular Chemistry in 2019.Application of 587-88-2 This article mentions the following:

The present work documents an operationally simple, clean and practical method for accessing the 2,2-disubstituted indolin-3-one (pseudoindoxyl) scaffold. The rhodium carbenoid mediated reaction between N-o-alkylamino benzoylbenzotriazoles and aryl diazoacetates occurs smoothly in water and exploits the leaving group ability of the benzotriazole moiety to install the carbonyl function in the product. Other highlights of the methodol. are a wide substrate scope and exptl. practicality given the re-use of the benzotriazole byproduct for starting material preparation In the experiment, the researchers used many compounds, for example, Ethyl 2-(4-fluorophenyl)acetate (cas: 587-88-2Application of 587-88-2).

Ethyl 2-(4-fluorophenyl)acetate (cas: 587-88-2) 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.Application of 587-88-2

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

Bio-based aliphatic/aromatic poly(trimethylene furanoate/sebacate) random copolymers: Correlation between mechanical, gas barrier performances and compostability and copolymer composition was written by Zubkiewicz, Agata;Szymczyk, Anna;Sablong, Rafael J.;Soccio, Michelina;Guidotti, Giulia;Siracusa, Valentina;Lotti, Nadia. And the article was included in Polymer Degradation and Stability in 2022.Formula: C12H22O4 This article mentions the following:

Highly promising fully biobased random copolyesters, poly(trimethylene 2,5-furandicarboxylate-co-trimethylene sebacate) (PTFcoPTSeb), were synthesized by using bio derived 1,3-propanediol, di-Me ester of 2,5- furandicarboxylic acid, and sebacic acid, through eco-friendly polycondensation in the melt. Copolymers with high mol. weight containing 5, 15, 25 mol % of PTSeb were obtained, and their chem. structure confirmed by ¹H NMR and FTIR spectroscopy. The thermal, tensile and gas barrier properties and composability were studied in relation to the copolymer supramol. structure. As expected, introduction of PTSeb co-units results in lowering of glass transition temperature of copolymers and improves their flexibility. Besides, all copolymers showed outstanding gas barrier properties to O₂ and CO₂, with copolymer containing 15 mol % of PTSeb showing exceptional gas barrier properties, better than those of PTF and comparable to those of EVOH, currently used in multilayer packaging films. The same copolymer exhibited temperature induced shape memory behavior. It was found that low amounts (15-25 mol %) of PTSeb in copolymer significantly modifies PTF thermal, mech. and barrier properties and renders the final material compostable. Copolyesters containing 15 and 25 mol % of PTSeb can compete in some applications with com. available compostable Ecoflex polymer, but with markedly improved barrier properties. In the experiment, the researchers used many compounds, for example, Dimethyl decanedioate (cas: 106-79-6Formula: C12H22O4).

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

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

Copper-Catalyzed Anomeric O-Arylation of Carbohydrate Derivatives at Room Temperature was written by Verdelet, Tristan;Benmahdjoub, Sara;Benmerad, Belkacem;Alami, Mouad;Messaoudi, Samir. And the article was included in Journal of Organic Chemistry in 2019.Synthetic Route of C16H22O11 This article mentions the following:

Direct and practical anomeric O-arylation of sugar lactols with substituted arylboronic acids has been established. Using copper catalysis at room temperature under an air atm., the protocol proved to be general, and a variety of aryl O-glycosides have been prepared in good to excellent yields. Furthermore, this approach was extended successfully to unprotected carbohydrates, including α-mannose, and it was demonstrated here how the interaction between carbohydrates and boronic acids can be combined with copper catalysis to achieve selective anomeric O-arylation. 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 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.Synthetic Route of C16H22O11

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

Quality, sensory and volatile profiles of fresh-cut big top nectarines cold stored in air or modified atmosphere packaging was written by Cozzolino, Rosaria;Cefola, Maria;Pace, Bernardo;Malorni, Livia;Martignetti, Antonella;Montemurro, Nicola;Pellicano, Mario Paolo. And the article was included in International Journal of Food Science and Technology in 2018.COA of Formula: C10H20O2 This article mentions the following:

Solid-phase microextraction (SPME) GC-MS was used to investigate the volatile organic compound (VOC) profile of fresh-cut ‘Big Top’ nectarine samples, stored in unsealed bags (AIR) or packed in active modified atm. (MAP) after 8 days of cold storage. Nectarine slices were also subjected to sensory and quality anal. after harvest and at the end of the storage. MAP preserved the overall quality, the appearance and the olfactory properties of nectarine slices during storage, while AIR samples showed symptoms of dehydration and browning. Sixty VOCs were identified in total in the headspace of the fresh nectarines and cold-stored fruit slices samples. Principal component anal. performed on VOCs allowed to differentiate fresh nectarines from cold-stored samples, with lactones and terpenes mainly related to fresh samples, and ester compounds pos. correlated to AIR or MAP samples. Partial least square regression models allowed to identify a pool of VOC predictors of olfactory sensory descriptors. In the experiment, the researchers used many compounds, for example, Isopentyl 3-methylbutanoate (cas: 659-70-1COA of Formula: C10H20O2).

Isopentyl 3-methylbutanoate (cas: 659-70-1) 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. COA of Formula: C10H20O2

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

Comparative study on the effect of two drying methods on the guest encapsulation behavior of osmanthus flavor-2-hydroxypropyl-β-cyclodextrin inclusion complex was written by Hu, Jing;Du, Peiting;Liu, Shanshan;Liu, Qinghe;Deng, Weijun. And the article was included in Flavour and Fragrance Journal in 2021.Name: 5-Hexyldihydrofuran-2(3H)-one This article mentions the following:

In this study, osmanthus flavor (OF) and HP-β-CD were used to prepare OF and HP-β-CD inclusion complex (OF-CD). OF-CD powders were obtained with oven-drying and freeze-drying, sep. The effect of drying methods was investigated with the morphol. and odor evaluation first. The chem. structure and flavor loading ratio of OF-CDs were determined by Fourier transform IR spectroscopy (FTIR) and Gas chromatog.-mass spectrometry (GC-MS). The flavor was successfully be encapsulated by HP-β-CD forming OF-CD inclusion complex. Oven-drying led to compact blocky solid, while freeze-drying resulted in porous morphol. The amount of flavor in OF-CD with oven-drying (48.61 μg[n.8260]g) was found lower than that in OF-CD with freeze-drying (58.1 μg[n.8260]g). In particular, the content of alcoholics in OF-CD with oven-drying (11.8 μg[n.8260]g) was much lower than that in OF-CD with freeze-drying (19.04 μg[n.8260]g). Thermogravimetric anal. (TGA) showed that the average activation energy of OF-CD with oven-drying (66.3-135.4 kJ mol-1) was higher than OF-CD with freeze-drying (53.0-100.7 kJ mol-1) by 13.3-34.7 kJ mol-1. More intermol. hydrogen bonds in OF-CD with freeze-drying led to high encapsulation of partial components; however, they are not thermostable, resulting in fast release at high temperature The better thermal stability of OF-CD with oven-drying makes itself a better candidate for flavor encapsulation for cooking at high temperature In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Name: 5-Hexyldihydrofuran-2(3H)-one).

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. 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.Name: 5-Hexyldihydrofuran-2(3H)-one

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

Decoding the Specific Roasty Aroma Wuyi Rock Tea (Camellia sinensis: Dahongpao) by the Sensomics Approach was written by Wang, Jing;Li, Mengru;Wang, Hui;Huang, Wenjing;Li, Fang;Wang, Lili;Ho, Chi-Tang;Zhang, Yanyan;Zhang, Liang;Zhai, Xiaoting;Wan, Xiaochun. And the article was included in Journal of Agricultural and Food Chemistry in 2022.Application of 868-57-5 This article mentions the following:

Aroma extract dilution anal. was performed on volatile fractions extracted from a freshly prepared Dahongpao (DHP) tea infusion using solvent-assisted flavor evaporation, yielding 65 odor-active domains with flavor dilution factors ranging between 32 and 32,768. In addition, six aromatic substances were captured by headspace anal. Quantitation of 54 compounds by an internal standard method and stable isotope dilution assays revealed that the concentrations of 32 odorants exceeded their resp. orthonasal odor threshold values in tea infusion. The results of odor activity values (OAVs) suggested that 2-metylbutanal (malty) and γ-hexalactone (coconut-like) had the highest OAVs (248 and 154). Eight odorants including γ-hexalactone (OAV 154), Me 2-methylbutanoate (59), phenylacetic acid (7.2), acetylpyrazine (5.7), 2-methoxyphenol (3.4), p-cresol (2.7), 2,6-diethylpyrazine (2.7), and vanillin (1.8) were newly identified as key odorants in DHP tea infusion. An aroma recombination model in a non-volatile matrix extracted from tea infusion satisfactorily mimicked the overall aroma of DHP tea infusion, thereby confirming the identification and quant. experiments Omission experiments verified the obvious significance of 6-methyl-5-hepten-2-one (OAV 91), 2-ethyl-3,5-dimethylpyrazine (19), 4-hydroxy-2,5-dimethylfuran-3(2H)-one (13), and acetylpyrazine (5.7) as key odorants for the special roasty and caramel-like aroma of DHP tea. In the experiment, the researchers used many compounds, for example, Methyl2-methylbutyrate (cas: 868-57-5Application of 868-57-5).

Methyl2-methylbutyrate (cas: 868-57-5) 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. Application of 868-57-5

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

Microwave-assisted synthesis of 5-substituted 2-aminothiophenes starting from arylacetaldehydes was written by Revelant, Germain;Dunand, Sandrine;Hesse, Stephanie;Kirsch, Gilbert. And the article was included in Synthesis in 2011.Category: esters-buliding-blocks This article mentions the following:

An easy three-step pathway for the synthesis of arylacetaldehydes from the corresponding carboxylic acids in very high yields is described. Their use as precursors of 5-substituted-2-aminothiophenes, e.g. I (R = CO₂Et, CN, CONH₂), is illustrated via a microwave-assisted Gewald reaction. This method allows obtaining the expected compounds in a shorter time and with better yields and purities than the classical procedures. In the experiment, the researchers used many compounds, for example, Methyl 2-thienylacetate (cas: 19432-68-9Category: esters-buliding-blocks).

Methyl 2-thienylacetate (cas: 19432-68-9) 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. Category: esters-buliding-blocks

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

Rational design of 4,5-disubstituted-5,7-dihydro-pyrrolo[2,3-d]pyrimidin-6-ones as a novel class of inhibitors of epidermal growth factor receptor (EGF-R) and Her2(p185^erbB) tyrosine kinases was written by Sun, Li;Cui, Jean;Liang, Congxin;Zhou, Yong;Nematalla, Asaad;Wang, Xueyan;Chen, Hui;Tang, Cho;Wei, James. And the article was included in Bioorganic & Medicinal Chemistry Letters in 2002.Application of 2199-49-7 This article mentions the following:

A novel class of 4,5-disubstituted-5,7-dihydro-pyrrolo[2,3-d]pyrimidin-6-ones has been discovered as potent and selective inhibitors of the EGF-R tyrosine kinase family. These compounds selectively inhibit EGF-R kinase activity at low nanomolar concentration and tyrosine autophosphorylation in cells expressing EGF-R or Her2 (p185^erbB). Structure-activity relationships (SARs) for this class of compounds are presented. In the experiment, the researchers used many compounds, for example, Ethyl 4-methyl-1H-pyrrole-3-carboxylate (cas: 2199-49-7Application of 2199-49-7).

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. 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 2199-49-7

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

Investigations of the Thermal Responsiveness of 1,4,2-Oxathiazoles was written by Hewitt, Russell J.;Ong, Michelle Jui Hsien;Lim, Yi Wee;Burkett, Brendan A.. And the article was included in European Journal of Organic Chemistry in 2015.HPLC of Formula: 27249-90-7 This article mentions the following:

The first systematic study of the thermal rearrangement/fragmentation of 5,5-disubstituted 1,4,2-oxathiazoles into isothiocyanates is reported. Structure-activity relations reveal that the choice of substituent at the 5-position of the 1,4,2-oxathiazoles is the predominant factor to influence the ease of fragmentation. 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. 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. 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