Tag: 100-200

In 2019,Food Research International included an article by Wu, Hualing; Huang, Wenjie; Chen, Zhongjian; Chen, Zhuang; Shi, Jingfang; Kong, Qian; Sun, Shili; Jiang, Xiaohui; Chen, Dong; Yan, Shijuan. Category: esters-buliding-blocks. The article was titled 《GC-MS-based metabolomic study reveals dynamic changes of chemical compositions during black tea processing》. The information in the text is summarized as follows:

The chem. composition of black tea during tea processing is in a state of flux. However, the dynamic changes of this sophisticated metabolic process are far from clear. GC-MS-based metabolomic analyses were performed to examine changes in volatile and non-volatile compounds throughout the five stages of tea processing. The results showed that the most striking differences were observed at the withering and rolling stages, during which 62 non-volatile and 47 volatile compounds were significantly changed. The levels of most monosaccharides decreased at the withering stage and increased in subsequent stages while di-saccharides decreased as the process progressed. Free amino acids increased sharply at the withering stage, and most kept increasing or remained stable afterwards. However, levels of catechin, epicatechin, epigallocatechin, and epigallocatechin gallate decreased after withering and remained at low levels afterwards. Among the 47 volatile compounds with altered levels, phenylpropanoids/benzenoids and carotenoid-derived volatiles, which contribute to the honey-like and rose-like fragrances and quality of Danxia2 tea, kept increasing during the processing, among them eight were newly produced. Furthermore, 19 volatiles with a grassy odor decreased during processing. This study provides a comprehensive profile of metabolic changes during black tea processing, which is potentially important for both quality control and improvement of the flavor of black teas. In the part of experimental materials, we found many familiar compounds, such as Methyl Salicylate(cas: 119-36-8Category: esters-buliding-blocks)

Methyl Salicylate(cas: 119-36-8) has been used: as a component of clarifying solution for treating Mongolian gerbil cochlea intact for immunofluorescence analysis, as a plant elicitor to test its effect on reducing the whitefly population from tomato plants.Category: esters-buliding-blocks

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

In 2017,Hsu, Wei-Shun; Tsai, Min-Huan; Barve, Indrajeet J.; Yellol, Gorakh S.; Sun, Chung-Ming published 《Synthesis of Aminofuran-Linked Benzimidazoles and Cyanopyrrole-Fused Benzimidazoles by Condition-Based Skeletal Divergence》.ACS Combinatorial Science published the findings.Electric Literature of C8H6FNO4 The information in the text is summarized as follows:

A condition-based skeletal divergent synthesis was explored to achieve skeletal diversity in two component condensation reaction. Cyanomethyl benzimidazole was reacted with α-bromoketone under thermal conditions to furnish 2-aminofuranyl-benzimidazoles, while the same reaction afforded 3-cyano-benzopyrrolo-imidazoles under microwave irradiation Two nonequivalent nucleophilic centers on benzimidazole moiety were manipulated elegantly by different reaction conditions to achieve the skeletal diversity. The experimental part of the paper was very detailed, including the reaction process of Methyl 4-fluoro-3-nitrobenzoate(cas: 329-59-9Electric Literature of C8H6FNO4)

Methyl 4-fluoro-3-nitrobenzoate(cas: 329-59-9) belongs to methyl benzoate. Methyl benzoate reacts at both the ring and the ester, depending on the substrate. Electrophiles attack the ring, illustrated by acid-catalysed nitration with nitric acid to give methyl 3-nitrobenzoate.Electric Literature of C8H6FNO4Methyl 4-fluoro-3-nitrobenzoate is used to prepare dimethyl 3-nitro-3′,4-oxydibenzoate by reacting with 3-hydroxy-benzoic acid methyl ester.

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

In 2016,Wang, Guangcheng; He, Dianxiong; Li, Xin; Li, Juan; Peng, Zhiyun published 《Design, synthesis and biological evaluation of novel coumarin thiazole derivatives as α-glucosidase inhibitors》.Bioorganic Chemistry published the findings.Category: esters-buliding-blocks The information in the text is summarized as follows:

A new series of coumarin thiazole derivatives 7a-7t were synthesized, characterized by 1H NMR, 13C NMR and element anal., evaluated for their α-glucosidase inhibitory activity. The majority of the screened compounds displayed potent inhibitory activities with IC50 values in the range of 6.24 ± 0.07-81.69 ± 0.39 μM, when compared to the standard acarbose (IC50 = 43.26 ± 0.19 μM). Structure-activity relationship (SAR) studies suggest that the pattern of substitution in the Ph ring is closely related to the biol. activity of this class of compounds Among all the tested mols., compound 7e (IC50 = 6.24 ± 0.07 μM) was found to be the most active compound in the library of coumarin thiazole derivatives Enzyme kinetic studies showed that compound 7e is a non-competitive inhibitor with a Ki of 6.86 μM. Furthermore, the binding interactions of compound 7e with the active site of α-glucosidase were confirmed through mol. docking. This study has identified a new class of potent α-glucosidase inhibitors for further investigation. In the experiment, the researchers used many compounds, for example, Ethyl 2-amino-2-thioxoacetate(cas: 16982-21-1Category: esters-buliding-blocks)

Ethyl 2-amino-2-thioxoacetate(cas: 16982-21-1) belongs to anime. Reduction of nitro compounds, RNO2, by hydrogen or other reducing agents produces primary amines cleanly (i.e., without a mixture of products), but the method is mostly used for aromatic amines because of the limited availability of aliphatic nitro compounds. Reduction of nitriles and oximes (R2C=NOH) also yields primary amines.Category: esters-buliding-blocks

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

In 2016,Chen, Li-Hsun; Chung, Tsai-Wen; Narhe, Bharat D.; Sun, Chung-Ming published 《A Novel Mechanistic Study on Ultrasound-Assisted, One-Pot Synthesis of Functionalized Benzimidazo[2,1-b]quinazolin-1(1H)-ones》.ACS Combinatorial Science published the findings.Safety of Methyl 4-fluoro-3-nitrobenzoate The information in the text is summarized as follows:

Ultrasound-assisted synthesis of benzimidazo[2,1-b]quinazolin-1(1H)-ones was achieved via piperidine-catalyzed three-component reaction of 2-aminobenzimidazoles, an aromatic aldehyde, and 1,3-dione in aqueous isopropanol. This mechanism was first suspected following our identification of unusual reaction intermediates in a one-pot reaction. An unprecedented coupling reaction, it involved a nucleophilic attack by 2-aminobenzimidazole on in situ generated Michael adduct, followed by electrocyclic ring formation reaction. In contrast to the commonly accepted mechanism, that the direct reaction of 2-amino benzimidazole with a Knoevenagel adduct cannot deliver target compounds In the part of experimental materials, we found many familiar compounds, such as Methyl 4-fluoro-3-nitrobenzoate(cas: 329-59-9Safety of Methyl 4-fluoro-3-nitrobenzoate)

Methyl 4-fluoro-3-nitrobenzoate(cas: 329-59-9) belongs to methyl benzoate. Methyl benzoate reacts at both the ring and the ester, depending on the substrate. Electrophiles attack the ring, illustrated by acid-catalysed nitration with nitric acid to give methyl 3-nitrobenzoate.Safety of Methyl 4-fluoro-3-nitrobenzoateMethyl 4-fluoro-3-nitrobenzoate is used to prepare dimethyl 3-nitro-3′,4-oxydibenzoate by reacting with 3-hydroxy-benzoic acid methyl ester.

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

In 2012,Munack, Steffi; Leroux, Vincent; Roderer, Kathrin; Oekvist, Mats; van Eerde, Andre; Gundersen, Lise-Lotte; Krengel, Ute; Kast, Peter published 《When Inhibitors Do Not Inhibit: Critical Evaluation of Rational Drug Design Targeting Chorismate Mutase from Mycobacterium tuberculosis》.Chemistry & Biodiversity published the findings.Reference of Methyl 4-fluoro-3-nitrobenzoate The information in the text is summarized as follows:

Tuberculosis (TB) is a devastating disease that claims millions of lives every year. Hindered access or non-compliance to medication, especially in developing countries, led to drug resistance, further aggravating the situation. With current standard therapies in use for over 50 years and only few new candidates in clin. trials, there is an urgent call for new TB drugs. A powerful tool for the development of new medication is structure-guided design, combined with virtual screening or docking studies. Here, we report the results of a drug-design project, which we based on a publication that claimed the structure-guided discovery of several promising and highly active inhibitors targeting the secreted chorismate mutase (*MtCM) from Mycobacterium tuberculosis. We set out to further improve on these compounds and synthesized a series of new derivatives Thorough evaluation of these mols. in enzymic assays revealed, to our dismay, that neither the claimed lead compounds, nor any of the synthesized derivatives, show any inhibitory effects against *MtCM. The results came from multiple reactions, including the reaction of Methyl 4-fluoro-3-nitrobenzoate(cas: 329-59-9Reference of Methyl 4-fluoro-3-nitrobenzoate)

Methyl 4-fluoro-3-nitrobenzoate(cas: 329-59-9) belongs to methyl benzoate. Methyl benzoate reacts at both the ring and the ester, depending on the substrate. Electrophiles attack the ring, illustrated by acid-catalysed nitration with nitric acid to give methyl 3-nitrobenzoate.Reference of Methyl 4-fluoro-3-nitrobenzoate

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

In 2011,Guernon, Jason M.; Wu, Yong-Jin published 《3-Bromocyclohexane-1,2-dione as a useful reagent for Hantzsch synthesis of thiazoles and the synthesis of related heterocycles》.Tetrahedron Letters published the findings.Name: Ethyl 2-amino-2-thioxoacetate The information in the text is summarized as follows:

The authors describe the use of 3-bromocyclohexane-1,2-dione, an air stable, versatile reagent for the Hantzsch thiazole synthesis and the synthesis of other closely related heterocycles. For example, cyclocondensation of 3-bromocyclohexane-1,2-dione with RC(S)NH2 (R = Ph, 4-pyridyl, t-Bu, etc.) gave I. After reading the article, we found that the author used Ethyl 2-amino-2-thioxoacetate(cas: 16982-21-1Name: Ethyl 2-amino-2-thioxoacetate)

Ethyl 2-amino-2-thioxoacetate(cas: 16982-21-1) belongs to anime. The reaction of alkyl halides, R―X, where X is a halogen, or analogous reagents with ammonia (or amines) is useful with certain compounds. Not all alkyl halides are effective reagents; the reaction is sluggish with secondary alkyl groups and fails with tertiary ones. Its usefulness is largely confined to primary alkyl halides (those having two hydrogen atoms on the reacting site).Name: Ethyl 2-amino-2-thioxoacetate

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

Xia, Qi; Li, Xiang; Fu, Xi; Zhou, Yaxuan; Peng, Yanqing; Wang, Jiayi; Song, Gonghua published an article in Journal of Organic Chemistry. The title of the article was 《Copper-Catalyzed Three-Component Reactions of α-Ketoaldehyde, 1,3-Dicarbonyl Compound, and Organic Boronic Acid in Water: A Route to 1,4-Diketones》.Quality Control of Methyl 3-oxovalerate The author mentioned the following in the article:

A novel three-component reaction of α-ketoaldehydes, 1,3-dicarbonyl compounds, and organic boronic acids catalyzed by CuO in water has been developed to give a wide range of products containing 1,3/1,4-diketones. The method has some advantages such as the use of readily available starting materials, wide substrate scopes, excellent yields, gram-scale synthesis, and mild reaction conditions. After reading the article, we found that the author used Methyl 3-oxovalerate(cas: 30414-53-0Quality Control of Methyl 3-oxovalerate)

Methyl 3-oxovalerate(cas: 30414-53-0) belongs to ketone compounds. Ketone compounds have important physiological properties. They are found in several sugars and in compounds for medicinal use, including natural and synthetic steroid hormones. Molecules of the anti-inflammatory agent cortisone contain three ketone groups.Quality Control of Methyl 3-oxovalerate

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

Wang, Yun-Peng; Fang, Kun; Tu, Yong-Qiang; Yin, Jun-Jie; Zhao, Qi; Ke, Tian published their research in Nature Communications on December 31 ,2022. The article was titled 《An efficient approach to angular tricyclic molecular architecture via Nazarov-like cyclization and double ring-expansion cascade》.Category: esters-buliding-blocks The article contains the following contents:

A modular and efficient method for constructing angular tri-carbocyclic architectures containing quaternary carbon center(s), e.g., I (R = Me) from 1,3-dicycloalkylidenyl ketones, e.g., II is established, which involves an unconventional synergistic cascade of a Nazarov cyclization and two ring expansions. It features high selectivity, mild conditions and convenient operation, wide scope and easy availability of substrate. Substitution at the 4πe-system with electron-donating group favors this reaction, while that with electron-withdrawing group or proton disfavors. The electron-donating group directs the initial ring expansion at its own site, while the p-π- or n-π- associated substituent favors selectively the later ring expansion near its location because of the beneficial maintenance of an original conjugated system. The stereoselectivity has proved to be governed by either the steric effect at the expanded rings, or the migration ability of the migrating atom. D. Functional Theory calculation suggests that the initial Nazarov cyclization would be the rate-determining step. A racemic total synthesis of the natural (±)-waihoensene is realized in 18 steps by use of this methodol. In the experiment, the researchers used many compounds, for example, Methyl 3-oxovalerate(cas: 30414-53-0Category: esters-buliding-blocks)

Methyl 3-oxovalerate(cas: 30414-53-0) belongs to ketone compounds. Ketone compounds have important physiological properties. They are found in several sugars and in compounds for medicinal use, including natural and synthetic steroid hormones. Molecules of the anti-inflammatory agent cortisone contain three ketone groups.Category: esters-buliding-blocks

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

Ruzi, Rehanguli; Liu, Kai; Zhu, Chengjian; Xie, Jin published their research in Nature Communications on December 31 ,2020. The article was titled 《Upgrading ketone synthesis direct from carboxylic acids and organohalides》.Synthetic Route of C9H8O4 The article contains the following contents:

A photoredox, nickel and phosphoranyl radical synergistic cross-electrophile coupling of com. available chems., aromatic acids RCO2H (R = 4-methylphenyl, thiophen-3-yl, naphthalen-2-yl, etc.) and aryl/alkyl bromides R1Br (R1 = 6-(trifluoromethyl)pyridin-3-yl, 2-cyanoethyl, quinolin-3-yl, etc.) was reported. This allows for concise synthesis of highly functionalized ketones RC(O)R1directly, without the preparation of activated carbonyl intermediates or organometallic compounds, and thus complements the conventional Weinreb ketone synthesis. Use of the appropriate photocatalyst, ligand amount and solvents can match the reaction rate required by any simple catalytic cycle. The practicality and synthetic robustness of the reaction are illustrated by the facile synthesis of complex ketones from readily available feedstock chems. In the experiment, the researchers used many compounds, for example, 3-(Methoxycarbonyl)benzoic acid(cas: 1877-71-0Synthetic Route of C9H8O4)

3-(Methoxycarbonyl)benzoic acid(cas: 1877-71-0) belongs to esters. 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. Synthetic Route of C9H8O4

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

《Physically mixed catalytic system of amino and sulfo-functional porous organic polymers as efficiently synergistic co-catalysts for one-pot cascade reactions》 was written by Sun, Zunming; Liu, Fuyao; Yang, Xinyue; Huang, Xianpei; Zhang, Mengmeng; Bian, Guomin; Qi, Yonglin; Yang, Xinlin; Zhang, Wangqing. Quality Control of Ethyl 3-oxopentanoateThis research focused onvinylsulfonate vinylbenzylamine polymer phys mixture recyclable catalyst; cyclohexenone arylidenecyanoacetate arylidenemalononitrile preparation; polymer mixture recyclable catalyst deacetalization Knoevenagel rearrangement reaction; dimethoxymethylbenzene tandem deacetalization Knoevenagel reaction recyclable polymer mixture catalyst; pyrancarboxylate rearrangement recyclable polymer mixture catalyst. The article conveys some information:

In this article, acid/base bi-functional polymeric materials were prepared using phys. mixed porous poly(divinylbenzene-co-4-vinylbenzenesulfonic acid) (P(DVB-VBS)) with sulfonic acid groups and poly(divinylbenzene-co-4-vinylbenzyl amine) (P(DVB-VBA)) with amino groups, which were synthesized by solvothermal polymerization of crosslinker DVB with either Ph 4-vinylbenzenesulfonate (PVBS) or 4-vinylbenzyl amine hydrochloride (VBAH) functional monomers together with subsequent hydrolyzation or alk. treatment. The bi-functional polymeric materials were utilized as a synergistic catalytic system for one-pot cascade reactions including deacetalization-Henry condensation reaction, deacetalization-Knoevenagel condensation reaction and the transformation of 3,4-dihydropyran derivatives to α-ester cyclohexenone compounds The crosslinked polymeric frameworks effectively isolated sulfonic acid and primary amine groups to ensure their roles as both acid and base catalyst simultaneously in a one-pot system. The hierarchical porosity of a phys. mixed acid/base co-catalyst system provided the possibility for the multi-step transformation of more complex substrates. The results came from multiple reactions, including the reaction of Ethyl 3-oxopentanoate(cas: 4949-44-4Quality Control of Ethyl 3-oxopentanoate)

Ethyl 3-oxopentanoate(cas: 4949-44-4) belongs to ketone compounds. They are most widely used as solvents, especially in industries manufacturing explosives, lacquers, paints, and textiles. Ketones are also used in tanning, as preservatives, and in hydraulic fluids.Quality Control of Ethyl 3-oxopentanoate

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