Month: February 2023

A new, modulated, oxidative ring-cleavage of α-nitro cycloalkanones by Oxone. Synthesis of α,ω-dicarboxylic acids and α,ω-dicarboxylic monomethyl esters was written by Ballini, Roberto;Curini, Massimo;Epifano, Francesco;Marcotullio, Maria Carla;Rosati, Ornelio. And the article was included in Synlett in 1998.COA of Formula: C13H24O4 This article mentions the following:

By the appropriate choice of the reaction conditions, Oxone produces the ring cleavage of α-nitro cycloalkanones affording good yields of α,ω-dicarboxylic acids and α,ω-dicarboxylic monomethyl esters, resp., regardless of the ring size and/or the presence of an alkyl group as substituent. In the experiment, the researchers used many compounds, for example, 12-Methoxy-12-oxododecanoic acid (cas: 3903-40-0COA of Formula: C13H24O4).

12-Methoxy-12-oxododecanoic acid (cas: 3903-40-0) 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.COA of Formula: C13H24O4

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

Selective monoesterification of the longer carbon chain in a mixture of dicarboxylic acids by adsorbing and aligning the acids on alumina was written by Ogawa, Haruo;Chihara, Teiji;Teratani, Shousuke;Taya, Kazuo. And the article was included in Journal of the Chemical Society, Chemical Communications in 1986.COA of Formula: C13H24O4 This article mentions the following:

When mixtures of dicarboxylic acids were absorbed on Al₂O₃ and treated with CH₂N₂ in vigorously agitated cyclohexane the longer carboxylic acid was selectively monomethylated. Thus, treating a mixture of HO₂C(CH₂)₁₀CO₂H and HO₂C(CH₂)₃CO₂H by the above procedure gave 89% MeO₂C(CH₂)₁₀CO₂H and 9% MeO₂C(CH₂)₃CO₂H. This selectivity is attributed to a perpendicular alignment of the acids with the Al₂O₃ surface that makes the nonabsorbed end of the longer acid more available to the CH₂N₂. In the experiment, the researchers used many compounds, for example, 12-Methoxy-12-oxododecanoic acid (cas: 3903-40-0COA of Formula: C13H24O4).

12-Methoxy-12-oxododecanoic acid (cas: 3903-40-0) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. 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: C13H24O4

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

Synthesis, Assembled Structures, and Optoelectronic Properties of Amphiphilic Block Copolymers Containing Anthracene Units in the Main Chain was written by Mori, Hideharu;Tanaka, Hiromi. And the article was included in Macromolecular Chemistry and Physics in 2011.Recommanded Product: 27249-90-7 This article mentions the following:

Novel amphiphilic block copolymers containing the anthracene unit in the main chain are synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of a cyclic monomer, 10-methylene-9,10-dihydroanthryl-9-spirophenylcyclopropane (MDS). A hydrophilic macro-chain transfer agent is prepared by RAFT polymerization of 2-hydroxyethyl acrylate (HEA). The polymerizations of MDS using the poly(HEA) afford amphiphilic block copolymers, in which the hydrophobic poly(MDS) segment has a perfectly alternating structure composed of an anthracene unit and a styrene unit, owing to the ring-opening polymerization system. Characteristic assembled structures and optoelectronic properties of the amphiphilic block copolymers are investigated in various selective solvents. In the experiment, the researchers used many compounds, for example, Benzyl benzodithioate (cas: 27249-90-7Recommanded Product: 27249-90-7).

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. 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.Recommanded Product: 27249-90-7

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

Chemical analysis of snus products from the United States and northern Europe was written by Lawler, Tameka S.;Stanfill, Stephen B.;Tran, Hang T.;Lee, Grace E.;Chen, Patrick X.;Kimbrell, J. Brett;Lisko, Joseph G.;Fernandez, Carolina;Caudill, Samuel P.;Rey de Castro, B.;Watson, Clifford H.. And the article was included in PLoS One in 2020.Synthetic Route of C9H10O3 This article mentions the following:

Snus is an oral tobacco product that originated in Sweden. Snus products are available as fine-cut loose tobacco or in pre-portioned porous “pouches.” Some snus products undergo tobacco pasteurization during manufacturing, a process that removes or reduces nitrite-forming microbes, resulting in less tobacco-specific nitrosamine content in the product. Some tobacco companies and researchers have suggested that snus is potentially less harmful than traditional tobacco and thus a potential smoking cessation aid or an alternative to continued cigarette consumption. Although snus is available in various countries, limited information exists on snus variants from different manufacturers. Moisture, pH, nicotine, and tobacco-specific N’-nitrosamines (TSNAs) were quantified in 64 snus products made by 10 manufacturers in the United States and Northern Europe (NE). Reported means, standard errors, and differences are least-square (LS) estimates from bootstrapped mixed effects models, which accounted for correlation among repeated measurements. Minor alkaloids and select flavors were also measured. Among all product types, moisture (27.4%-59.5%), pH (pH 5.87-9.10), total nicotine (6.81-20.6 mg/g, wet), unprotonated nicotine (0.083-15.7 mg/g), and total TSNAs (390-4,910 ng/g) varied widely. The LS-mean unprotonated nicotine concentration of NE portion (7.72 mg/g, SE = 0.963) and NE loose (5.06 mg/g, SE = 1.26) snus were each significantly higher than US portion snus (1.00 mg/g, SE = 1.56). Concentrations of minor alkaloids varied most among products with the highest total nicotine levels. The LS-mean NNN+NNK were higher in snus sold in the US (1360 ng/g, SE = 207) than in NE (836 ng/g, SE = 132) countries. The most abundant flavor compounds detected were pulegone, eucalyptol, and menthol. Phys. and chem. characteristics of US and NE products labeled as snus can vary considerably and should not be considered “equivalent”. Our findings could inform public health and policy decisions pertaining to snus exposure and potential adverse health effects associated with snus. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxybenzoate (cas: 118-61-6Synthetic Route of C9H10O3).

Ethyl 2-hydroxybenzoate (cas: 118-61-6) 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. 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.Synthetic Route of C9H10O3

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

Solvent selection for extractive distillation processes to separate close-boiling polar systems was written by Sprakel, Lisette M. J.;Kamphuis, Peter;Nikolova, Anna L.;Keijsper, Dylan J.;Schuur, Boelo. And the article was included in Chemical Engineering Research and Design in 2019.Recommanded Product: Methyl2-methylbutyrate This article mentions the following:

Solvent selection is key in extractive distillation process development and solvent effects are often predicted based on the activity coefficients at infinite dilution For close-boiling polar systems with strong or specific interacting species, standard simulation tools, e.g. using UNIFAC or COSMO-RS, often predict poor as the activity coefficients at infinite dilution not always reflect the selectivity in the process. For these systems, a heuristic solvent selection method in which mol. properties such as acidity, hydrogen bonding and polarity are applied is desired as first estimate in the solvent selection. To explore the key parameters for such a first selection, solvent effects on the relative volatility (α) were measured for three different industrially relevant polar mixtures, valeric acid – 2-methylbutyric acid, diethylmethylamine – diisopropylether, and 2-butanol – 2-butanone. For each of the cases the effect of potential solvents on α was measured in an ebulliometer. For the acids, the difference in pK_a of 0.1 was too small to sep. based on acidity with a moderately basic solvent. Stronger basic solvents resulted in thermal and chem. instability. Although the solvent methyl-2-Me butyrate is not suitable as a solvent because of reactivity, this structurally similar solvent showed selectivity, indicating also in extractive distillation the like dissolves like phenomenon can be applied to induce selectivity. A larger difference in basicity of the mixture components (amine-ether mixture) and a difference in hydrogen bonding affinity between the mixture components (ketone-alc. mixture) allowed for increasing α based on differences in acidity and hydrogen bonding, resp. In the experiment, the researchers used many compounds, for example, Methyl2-methylbutyrate (cas: 868-57-5Recommanded Product: Methyl2-methylbutyrate).

Methyl2-methylbutyrate (cas: 868-57-5) 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.Recommanded Product: Methyl2-methylbutyrate

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

Elution behavior of a 3D-printed, milled and conventional resin-based occlusal splint material was written by Wedekind, Lennart;Gueth, Jan-Frederik;Schweiger, Josef;Kollmuss, Maximilian;Reichl, Franz-Xaver;Edelhoff, Daniel;Hoegg, Christof. And the article was included in Dental Materials in 2021.Application of 84-61-7 This article mentions the following:

The elution of unpolymerized (co-)monomers and additives from methacrylic resin-based materials like polymethyl methacrylate (PMMA) can cause adverse side effects, such as mutagenicity, teratogenicity, genotoxicity, cytotoxicity and estrogenic activity.The aim of this study was to quantify the release and the cytotoxicity of residual (co-)monomers and additives from PMMA-based splint materials under consideration of real splint sizes. Three different materials used for additive (3D printing), subtractive (milling) and conventional (powder and liquid) manufacturing were examinedThe splint materials SHERAprint-ortho plus (additive), SHERAeco-disk PM20 (subtractive) and SHERAORTHOMER (conventional) were analyzed. 16 (n = 4) sample disks of each material (6 mm diameter and 2 mm height) were polished on the circular and one cross-section area and then eluted in both distilled water and methanol. The disks were incubated at 37°C for 24 h or 72 h and subsequently analyzed by gas chromatog./mass spectrometry (GC/MS) for specifying and quantifying released compounds XTT-based cell viability assays with human gingival fibroblasts (HGFs) were performed for Tetrahydrofurfuryl methacrylate (THFMA), 1,4-Butylene glycol dimethacrylate (BDDMA) and Tripropylenglycol diacrylate (TPGDA). In order to project the disk size to actual splint sizes in a worst-case scenario, lower and upper jaw occlusal splints were designed and volumes and surfaces were measured.For SHERAeco-disk PM20 and for SHERAORTHOMER no elution was determined in water. SHERAprint-ortho plus eluted the highest THFMA concentration of 7.47μ mol/l ±2,77μmol/l after 72 h in water. Six (co-)monomers and five additives were detected in the methanol eluates of all three materials tested. The XTT-based cell viability assays resulted in a EC50 of 3006 ± 408μmol/l for THFMA, 2569.5 ± 308μmol/l for BDDMA and 596.7 ± 88μmol/l for TPGDA.With the solvent methanol, released components from the investigated splint materials exceeded cytotoxic concentrations in HGFs calculated for a worst-case scenario in splint size. In the water eluates only the methacrylate THFMA could be determined from SHERAprint-ortho plus in concentrations below cytotoxic levels in HGFs. In the experiment, the researchers used many compounds, for example, Dicyclohexyl phthalate (cas: 84-61-7Application of 84-61-7).

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

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

Combined use of analyte protectants and precolumn backflushing for a robust, high-throughput quantitative determination of aroma compounds in cigarette mainstream smoke by gas chromatography-tandem mass spectrometry was written by Guo, Qiong;Pan, Lining;Qin, Yaqiong;Xie, Fuwei;Wang, Xiaoyu;Zhao, Xiaodong;Chen, Li;Wang, Bing;Cai, Junlan;Liu, Huimin. And the article was included in Microchemical Journal in 2022.Electric Literature of C6H12O2 This article mentions the following:

Trace anal. of multi-targets in complex matrixes such as cigarette smoke has always been a great challenge for analysts. In this paper, a high-throughput qual. and quant. method was developed and validated to determine 559 aroma compounds in mainstream smoke using gas chromatog.-tandem mass spectrometry. Among four commonly used extraction solvents, dichloromethane showed obvious advantages in extracting the target aroma compounds with different polarity. An analyte protectant mixture consisting of 3-methoxy-1,2-propanediol, 1,2-octandiol, 1,2-nonanediol, and 1,2-tetradecanediol was first presented to compensate for the matrix effect, which was suitable for solvents of a wide polarity range such as hexane, dichloromethane, acetone, acetonitrile, and methanol. Moreover, the introduction of precolumn backflushing markedly improved the instrument robustness in analyzing complex cigarette smoke. The results showed that the system retained good stability after 30 days of injection. The proposed method performed well in terms of key validation parameters: accuracy (70.3-118.8% for 552 compounds), inter/intraday precision (0.1-10.7% and 0.2-18.2%), and sensitivity (limit of detection 0.12-102.54 ng/mL). Finally, this method was successfully applied to analyze 12 different com. cigarette brands. The proposed method has good application prospects based on its robustness and may be used as a potential tool to transfer the cigarette design from an experience-dependent mode to a digital design mode. This method also shows potential in assaying aroma compounds in essentials, food or plant-based substrates. In the experiment, the researchers used many compounds, for example, Methyl2-methylbutyrate (cas: 868-57-5Electric Literature of C6H12O2).

Methyl2-methylbutyrate (cas: 868-57-5) 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.Electric Literature of C6H12O2

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

Synthesis of 4-(4-acetyl-5-methyl-1h-pyrrol-2-yl)-2′,3′,4′-trihydroxybutyl cinnamate and its application in unblended cigarette was written by Qi, Ling-kai;Wang, Jian-ling;Ji, Xiao-ming;Zhao, Ming-qin;Fu, Pei-pei. And the article was included in Jingxi Huagong in 2013.Application In Synthesis of Methyl 2-thienylacetate This article mentions the following:

Under alk. conditions and in aqueous solution, 2-methyl-3-acetyl-5-1′, 2′, 3′, 4′-tetrahydroxy Bu pyrrole was obtained by the reaction of D-glucosamine hydrochloride with acetyl acetone at reflux for 8 h. Then, this chem. compound was taken as raw material to react with cinnamic acid to synthesize the 4- (4-acetyl-5-methyl-1H-pyrrol-2-yl)-2′,3′,4′-trihydroxybutyl cinnamate in the presence of DCC which was used as dehydrating agent. Its structure was characterized and verified by ¹HNMR, ¹³CNMR, IR, and HRMS spectral anal. The pyrolysis of the target product was studied at 300°C, 600°C, and 900°C resp., and the application of the product in cigarette flavoring was studied as well. The results show that such aroma components as benzaldehyde, 2-Me pyridine and farnesol were detected at the three temperatures It is proved that when 0.2% of the target product was added in tobacco, it could play an important role in enhancing the aroma quality and volume of smoke, reducing irritancy and improving the aftertaste. In the experiment, the researchers used many compounds, for example, Methyl 2-thienylacetate (cas: 19432-68-9Application In Synthesis of Methyl 2-thienylacetate).

Methyl 2-thienylacetate (cas: 19432-68-9) 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. 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 In Synthesis of Methyl 2-thienylacetate

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

Peptide inhibitors of IκB protease: modification of the C-termini of Z-LLF-CHO was written by Suto, Mark J.;Sullivan, Robert W.;Ransone, Lynn J.. And the article was included in Bioorganic & Medicinal Chemistry Letters in 1996.Formula: C16H24N2O4 This article mentions the following:

A series of tripeptides (Z-Leu-Leu-Phe-R; where R is a modified C-terminus) were synthesized and evaluated for their ability to prevent the activation of NF-κB (nuclear factor κB) through the inhibition of IκB protease. Of the compounds evaluated, only the C-terminal aldehydes, Z-Leu-Leu-Phe-CHO and Z-Leu-Leu-D-Phe-CHO, were active in the Jurkat T-cell based assay. Z-Leu-Leu-Phe-CHO also decreased IL-2 and IL-8 levels in these cells indicating that inhibitors of IκB protease can have an effect on various signaling pathways. In the experiment, the researchers used many compounds, for example, (S)-tert-Butyl (1-(methoxy(methyl)amino)-1-oxo-3-phenylpropan-2-yl)carbamate (cas: 87694-53-9Formula: C16H24N2O4).

(S)-tert-Butyl (1-(methoxy(methyl)amino)-1-oxo-3-phenylpropan-2-yl)carbamate (cas: 87694-53-9) 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.Formula: C16H24N2O4

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

Noncovalent Organocatalytic Synthesis of Enantioenriched Terminal Aziridines with a Quaternary Stereogenic Center was written by De Fusco, Claudia;Fuoco, Tiziana;Croce, Gianluca;Lattanzi, Alessandra. And the article was included in Organic Letters in 2012.Application In Synthesis of Ethyl 3-oxo-3-(m-tolyl)propanoate This article mentions the following:

A high-yielding and enantioselective access to novel N-Boc terminal aziridines, bearing a quaternary stereogenic center, has been developed via an aza-Michael initiated ring-closure (aza-MIRC) reaction of α-acyl acrylates with an N-tosyloxy tert-Bu carbamate catalyzed by a chiral amino thiourea. The feasibility of the aziridine regioselective ring-opening to valuable α,α-disubstituted α-amino acid esters has been demonstrated. In the experiment, the researchers used many compounds, for example, Ethyl 3-oxo-3-(m-tolyl)propanoate (cas: 33166-79-9Application In Synthesis of Ethyl 3-oxo-3-(m-tolyl)propanoate).

Ethyl 3-oxo-3-(m-tolyl)propanoate (cas: 33166-79-9) 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. 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 Ethyl 3-oxo-3-(m-tolyl)propanoate

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