Tag: 100-200

A Novel Reaction for Annulation onto α,β-Unsaturated Ketones: W(CO)₅·L Promoted Exo- and Endo-Selective Cyclizations of ω-Acetylenic Silyl Enol Ethers Prepared by 1,4-Addition of Propargyl Malonate to Enones was written by Iwasawa, Nobuharu;Maeyama, Katsuya;Kusama, Hiroyuki. And the article was included in Organic Letters in 2001.Quality Control of Diethyl 2-(prop-2-yn-1-yl)malonate This article mentions the following:

Tungsten carbonyl catalysts promoted five- and six-membered ring annulations onto α,β-unsaturated ketones via cyclizations of acetylenic silyl enol ether intermediates. Thus, 1,4-addition of di-Et propargylmalonate to α,β-unsaturated ketones, e.g. cycloalkenones I (0-3) or PhCOCH:CHR¹ (R¹ = Ph, Me), in the presence of silyl triflates gave siloxy enynes, e.g. II (R¹Si = Me₃CSiMe₂, i-Pr₃Si) and siloxyhepenynes III, in good yield. W(CO)₅·THF and W(CO)₆ catalyzed photochem. cyclization of these intermediates gave either exo-cyclized products, e.g. methylenecyclopentanes IV and V, or endo-cyclized products, e.g. bicyclic ketones VI and benzoylcyclohexenes VII, in good yields simply by changing the reaction solvent. In the experiment, the researchers used many compounds, for example, Diethyl 2-(prop-2-yn-1-yl)malonate (cas: 17920-23-9Quality Control of Diethyl 2-(prop-2-yn-1-yl)malonate).

Diethyl 2-(prop-2-yn-1-yl)malonate (cas: 17920-23-9) 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. 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.Quality Control of Diethyl 2-(prop-2-yn-1-yl)malonate

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

Bisarylureas based on 1H-Pyrazolo[3,4-d]pyrimidine scaffold as novel pan-RAF inhibitors with potent anti-proliferative activities: structure-based design, synthesis, biological evaluation and molecular modelling studies was written by Fu, Yu;Wang, Yuanyuan;Wan, Shanhe;Li, Zhonghuang;Wang, Guangfa;Zhang, Jiajie;Wu, Xiaoyun. And the article was included in Molecules in 2017.HPLC of Formula: 16413-26-6 This article mentions the following:

RAF (Ras activating factor) kinases are important and attractive targets for cancer therapy. With the aim of discovering RAF inhibitors that bind to DFG-out inactive conformation created by the movement of Asp-Phe-Gly (DFG), we conducted structure-based drug design using the X-ray cocrystal structures of BRAF (v-raf murine sarcoma viral oncogene homolog B1), starting from bisarylurea derivative based on 1H-pyrazolo[3,4-d]pyrimidine scaffold 1a. Most of the synthesized compounds showed good to excellent inhibitory activities against BRAF^V600E kinase, possessed moderate to potent anti-proliferative activities against four tumor cell lines (A375, HT-29, PC-3 and A549) and good selectivity towards cancer cells rather normal cells (Madin-Darby canine kidney, MDCK). The most promising compound, 1v, exhibited potent inhibitory activity against not only BRAF^V600E (half maximal inhibitory concentration, IC₅₀ = 23.6 nM) but also wild-type BRAF (IC₅₀ = 51.5 nM) and C-RAF (IC₅₀ = 8.5 nM), and effective cellular anti-proliferative activities against A375, HT-29, PC-3 and A549 cell lines as well as a very good selectivity profile. Moreover, compound 1v mainly arrested the A375 cell line in the G0/G1 stage, and showed significant suppression of MEK (mitogen-activated protein kinase kinase) phosphorylation in A375 and HT-29 cell lines. Taken together, the optimal compound 1v showed excellent in vitro potency as a pan-RAF inhibitor. In addition, the promise of compound 1v was further confirmed by mol. dynamics simulation and binding free energy calculations In the experiment, the researchers used many compounds, for example, 3-Cyanophenylisocyanate (cas: 16413-26-6HPLC of Formula: 16413-26-6).

3-Cyanophenylisocyanate (cas: 16413-26-6) 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.HPLC of Formula: 16413-26-6

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

Identification of changes in the volatile compounds of robusta coffee beans during drying based on HS-SPME/GC-MS and E-nose analyses with the aid of chemometrics was written by Zhang, Ke;Cheng, Jinhuan;Hong, Qidi;Dong, Wenjiang;Chen, Xiaoai;Wu, Guiping;Zhang, Zhenzhen. And the article was included in LWT–Food Science and Technology in 2022.Related Products of 118-61-6 This article mentions the following:

In this study, headspace solid-phase microextraction/gas chromatog.-mass spectrometry (HS-SPME/GC-MS) and electronic-nose (E-nose) analyses were performed to examine the comprehensive flavor profiles of robusta coffee during heat air drying. A total of 62 volatile compounds were identified by HS-SPME/GC-MS, the level of acids, aldehydes, alcs. and esters decreased during drying process, however, the relative content of hydrocarbons and acids increased. Principal component anal. of the E-nose results clearly differentiated the samples related to drying time, and it was found that samples of initial stages (0 h, 3 h, and 6 h) had strong pos. with different sensors. Partial least squares-discriminant anal. (PLS-DA) indicated that alcs., ketones, and esters were the main contributing compounds to the flavor of coffee beans. The VIP score of PLS-DA larger than one illustrated that T30/1, T70/2, PA/2, and P30/2 were pos. with ketones, sulfur compounds, and esters. These results could provide theor. evidence about the change rule in volatile compounds of coffee beans during drying process, and could be applied to other thermally sensitive tropical agricultural products. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxybenzoate (cas: 118-61-6Related Products of 118-61-6).

Ethyl 2-hydroxybenzoate (cas: 118-61-6) 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. 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.Related Products of 118-61-6

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

Alcohol assisted C-C bond breaking: copper-catalyzed deacetylative α-arylation of β-keto esters and amides was written by Ke, Jie;He, Chuan;Liu, Huiying;Xu, Huan;Lei, Aiwen. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2013.Recommanded Product: 587-88-2 This article mentions the following:

A method of alc.-assisted copper-catalyzed highly selective deacetylative α-arylation of β-keto esters and amides has been demonstrated, which illustrated an efficient example of achieving α-aryl esters and amides. From the synthetic point of view, this arylation protocol is general and practical, representing a simple way to produce α-arylated carbonyl compounds from basic starting materials at low cost. In the experiment, the researchers used many compounds, for example, Ethyl 2-(4-fluorophenyl)acetate (cas: 587-88-2Recommanded Product: 587-88-2).

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: 587-88-2

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

Substituted 3-diazoacetylpyridine and some transformation products. Preparation of β-homoquinolinic and β-homonicotinic acids was written by Miescher, K.;Kagi, H.. And the article was included in Helvetica Chimica Acta in 1941.Related Products of 14667-47-1 This article mentions the following:

2-Aminonicotinic acid (50 g.) was added to 100 g. PCl₅ in 100 cc. AcCl. After 4 h. at room temperature the yellow crystalline precipitate of 2-aminonicotinyl chloride-HCl (I) was collected on a fritted glass filter and washed wih CH₂Cl₂. Yield 93% of theor. When I was dissolved in water at 0° and treated with K₂-CO₃ in the presence of Et₂O the freed 2-aminonicotinyl chloride (II) went into the Et₂O layer. II is a yellow crystalline powder, decomposing at about 110°. Heated with MeOH it gave the Me ester, m. 85°. To 75 g. CH₂N₂ in 4 l. of CH₂Cl₂ 70 g. of I was slowly added with stirring and cooling. 2-Amino-3-diazoacetylpyridine (III) (47.5 g.) was obtained as a yellow crystalline powder, decomposing at 163°. III treated with N H₂SO₄ slowly lost N₂ and was converted partly into 2-amino-3-hydroxyacetylpyridine, brown platelets, m. 139.5°, soluble in water and EtOH; and partly into 2-amino-3-hydroxyacetylpyridine monosulfuric ester, C₇H₈N₂O₅S, white crystals m. above 350°, sparingly soluble in water. III with HCl lost N and, after addition of AcONa as a buffer, 2-amino-3-chloroacetylpyridine precipitated It crystallized from MeOH as a yellow powder, m. 146° (decomposition). In like manner III with HBr gave 2-amino-3-bromoacetylpyridine (IV), a yellow microcrystalline powder, m. 113°. The HBr salt of IV formed yellow needles, soluble in water, m. 217° (decomposition). IV with hexamethylenetetramine in CHCl₃ gave 98% of yellow 2-amino-3-aminoacetylpyridine (V). The di-HBr salt of V is yellow, nearly insoluble in water or MeOH, and decomposes 254°. III warmed with anhydrous HCO₂H lost N and, after neutralization with Na₂CO₃, gave the ester, 2-amino-3-formyloxyacetylpyridine, as a brown powder, m. 143° (decomposition). In like manner III with AcOH gave 2-amino-3-acetoxyacetylpyridine. It crystallized from water in colorless leaflets, m. 139°. This same compound was also prepared by boiling IV with aqueous AcONa. To 1 l. of CH₂Cl₂ containing 19 g. CH₂N₂ and cooled to -10°, 40 g. of quinolinic acid 2-Me ester 3-chloride was slowly added. This converted the 3-COCl group to -COCH:N₂, forming 2-carbomethoxy-3-diazoacetylpyridine (VI) which, after solution in MeOH and precipitation by Et₂O, was obtained as a yellow powder, m. 68-70°, and losing N at about 100°. VI, dissolved in MeOH and shaken with Ag₂O, slowly lost N and was converted into β-homoquinolinic acid di-Me ester (yield 50-70%), a yellow oil, b_0.05 105°, soluble in water. Heated with 5 N aqueous NaOH, then acidified with HCl, this ester gave β-homoquinolinic acid, white glistening crystals, m. 182-3°. This acid when heated to 180° in PhNMe₂ lost CO₂, forming β-homonicotinic acid, m. 144°. This in turn, at high temperature, lost CO₂, forming 2-picoline. In the experiment, the researchers used many compounds, for example, Methyl 2-aminonicotinate (cas: 14667-47-1Related Products of 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. 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.Related Products of 14667-47-1

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

Essential oils and volatile emission of eight South African species of Helichrysum grown in uniform environmental conditions was written by Najar, B.;Cervelli, C.;Ferri, B.;Cioni, P. L.;Pistelli, L.. And the article was included in South African Journal of Botany in 2019.Related Products of 659-70-1 This article mentions the following:

This paper reported for the first time the aroma profile and essential oil composition of eight species of Helichrysum endemic in South Africa but grown in Italy (CREA-Sanremo collection). The volatiles of all the studied Helichrysum were dominated by monoterpene hydrocarbons, except for H. basalticum, where sesquiterpene hydrocarbons was the main class of compounds with β-caryophyllene (13.7%) and α-guaiene (11.9%) as major components.Despite the great diversity of compounds obtained in the volatile emission (more than 130), only four compounds were responsible for at least 34% of the identified fraction. These compounds were: sabinene (16.0%), β-caryophyllene and α-guaiene in H. basalticum; sabinene (57.7%) in H. foetidum; (Z)-β-ocimene (34.6%), tricyclene (16.2%) and myrcene (10.0%) in H. incanatum; myrcene (29.3%), tricyclene (21.5%) and limonene in H. indicum; tricyclene (32.1%) and (E)-3-hexanol acetate (20.1%) in H. montanum; limonene (10.3%), sabinene (8.9%), 1-decene (7.6%) and 1-hexanol (7.0%) in H. mutabile; α- and β-pinene in H. patulum (27.6% and 44.9%, resp.) and α-pinene (36.3%) and α-fanchene(15.6%) in H. setosum.The EOs composition of these species was also different from each other with sesquiterpene compounds as the prevalent class. Valerianol (16.3%, os, in H. basalticum), ledol (16.3%, os, in H. foetidum), β-caryophyllene (11.0% and 13.4%, sh, in H. indicum and H. patulum, resp.), viridiflorol (18.3%, os, in H. montanum) and valerianol (30.1%, os in H. setosum) were found to be the main constituents. It is worthy to highlighting that the H. incarnatum EO showed a similar behavior to that of the spontaneous emission with a predominance of monoterpene hydrocarbons (60.7% in EO vs 81.4% in VOC), both represented by (Z)-β-ocimene as main constituent. In the experiment, the researchers used many compounds, for example, Isopentyl 3-methylbutanoate (cas: 659-70-1Related Products of 659-70-1).

Isopentyl 3-methylbutanoate (cas: 659-70-1) 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.Related Products of 659-70-1

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

Antioxidant activity, and volatile and phytosterol contents of Strobilanthes crispus dehydrated using conventional and vacuum microwave drying methods was written by Chua, Lisa Yen Wen;Chua, Bee Lin;Figiel, Adam;Chong, Chien Hwa;Wojdylo, Aneta;Szumny, Antoni;Choong, Thomas Shean Yaw. And the article was included in Molecules in 2019.Computed Properties of C9H10O3 This article mentions the following:

The preservation of active constituents in fresh herbs is affected by drying methods. An effective drying method for Strobilanthes crispus which is increasingly marketed as an important herbal tea remains to be reported. This study evaluated the e ects of conventional and new drying technologies, namely vacuum microwave drying methods, on the antioxidant activity and yield of essential oil volatiles and phytosterols. These drying methods included convective drying (CD) at 40 °C, 50 °C, and 60 °C; vacuum microwave drying (VMD) at 6, 9, and 12 W/g; convective pre-drying and vacuum microwave finish drying (CPD-VMFD) at 50 °C and 9 W/g; and freeze-drying (FD). GC-MS revealed 33 volatiles, and 2-hexen-1-ol, 2-hexenal, 1-octen-3-ol, linalool, and benzaldehyde were major constituents. The compounds β-sitosterol and α-linolenic acid were the most abundant phytosterol and fatty acid, resp., in fresh S. crispus. The highest phenolic content was achieved with CD at 60 °C. The highest antioxidant activity was obtained with CD at 40 °C and VMD at 9 W/g. On the contrary, the highest total volatiles and phytosterols were detected with CD at 50 °C and VMD at 9 W/g, resp. This study showed that CD and VMD were effective in producing highly bioactive S. crispus. A suitable drying parameter level, irresp. of the drying method used, was an important influencing factor. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxybenzoate (cas: 118-61-6Computed Properties 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. 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.Computed Properties of C9H10O3

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

Synthesis of Hydantoins and Thiohydantoins Spiro-Fused to Pyrrolidines: Druglike Molecules Based on the 2-Arylethyl Amine Scaffold was written by Blanco-Ania, Daniel;Hermkens, Pedro H. H.;Sliedregt, Leo A. J. M.;Scheeren, Hans W.;Rutjes, Floris P. J. T.. And the article was included in Journal of Combinatorial Chemistry in 2009.Related Products of 16413-26-6 This article mentions the following:

The synthesis of a 144-compound library of hydantoins and thiohydantoins spiro-fused to pyrrolidines, e.g. I (R = Et, t-Bu, phenethyl, etc.), is described. These compounds are synthesized from β-aryl pyrrolidines, providing products with the 2-arylethyl amine moiety, a structural feature often encountered in compounds active in the central nervous system. All possible stereoisomers of the two-stereocenter products are synthesized. The 80-membered hydantoin sublibrary was obtained with yields ranging from 58 to 100% (87% average) and purities from 51 to 100% (87% average) and the 64-membered thiohydantoin sublibrary was obtained with yields ranging from 65 to 100% (89% average) and purities from 67 to 100% (93% average). In the experiment, the researchers used many compounds, for example, 3-Cyanophenylisocyanate (cas: 16413-26-6Related Products of 16413-26-6).

3-Cyanophenylisocyanate (cas: 16413-26-6) 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.Related Products of 16413-26-6

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

Characterization of Key Aroma Compounds in Tartary Buckwheat (Fagopyrum tataricum Gaertn.) by Means of Sensory-Directed Flavor Analysis was written by Shi, Jie;Tong, Guoqiang;Yang, Qiang;Huang, Mingquan;Ye, Hong;Liu, Yuancai;Wu, Jihong;Zhang, Jinglin;Sun, Xiaotao;Zhao, Dongrui. And the article was included in Journal of Agricultural and Food Chemistry in 2021.Application In Synthesis of 5-Hexyldihydrofuran-2(3H)-one This article mentions the following:

The key odorants of tartary buckwheat (TB) were researched by a sensory-directed flavor anal. approach for the first time. After the volatiles of TB were isolated by solvent-assisted flavor evaporation (SAFE), 49 aroma-active components with flavor dilution (FD) factors in the range of 1-2187 were identified using gas chromatog.-olfactometry-mass spectrometry (GC-O-MS) combined with aroma extract dilution anal. (AEDA). Geranylacetone, phenethyl alc., and β-damascone showed the highest FD factors of 2187. All 49 odorants were further quantitated by the internal standard curve method, and their odor activity values (OAVs) were obtained. The overall aroma of TB was successfully simulated (similarity > 98.16%) by mixing 16 odorants (OAV ≥ 1) with their natural concentrations The omission tests revealed that geosmin, α-isomethylionone, α-methylionone, β-ionone, linalool, β-damascone, geranylacetone, guaiacol, Et hexanoate, geraniol, vanillin, tetrahydrolinalool, and 2,5-dimethyl-4-hydroxy-3-(2H)-furanone were the key odorants of TB. Chiral anal. showed that tetrahydrolinalool and linalool existed as racemics in the com. TB. The relative content of R-enantiomers of α-isomethylionone and α-methylionone was slightly higher than that of their S-enantiomers. The odor thresholds of R- and S-enantiomer of tetrahydrolinalool were first detected as 0.029 and 3.8μg/L in air, resp. In the experiment, the researchers used many compounds, for example, 5-Hexyldihydrofuran-2(3H)-one (cas: 706-14-9Application In Synthesis of 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. 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.Application In Synthesis of 5-Hexyldihydrofuran-2(3H)-one

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

Investigation of volatile organic compounds in museum storage areas was written by Alvarez-Martin, Alba;Wilcop, Mary;Anderson, Rachel;Wendt, Diane;Barden, Richard;Kavich, Gwenaelle M.. And the article was included in Air Quality, Atmosphere & Health in 2021.Formula: C9H10O3 This article mentions the following:

This study investigates the complex mixture of volatile organic compounds (VOCs) released by and accumulated within a collection of historic medicinal, pharmaceutical, and cosmetic artifacts housed at the National Museum of American History (Smithsonian Institution). In recent years, staff have become concerned, both for the safety of the objects and for personnel working in the collection, about strong unremediated odors accumulating within several storage cabinets. Museum staff also wondered if non-odorous off-gassing might need remediation. Solid-phase microextraction combined with gas chromatog.-mass spectrometry anal. (SPME-GC-MS) was used to identify VOCs present in the storage room housing the collection. Over 160 compounds were detected and identified overall. Among these, 49 appeared to be directly related to ingredients used in the manufacture of many collection items. The results of the study suggest that SPME-GC-MS can be a strong tool for the rapid screening of multicomponent museum collections exhibiting off-gassing problems, before the pursuit of other more tedious anal. approaches. Addnl., the study reveals valuable insight into the characteristic volatile emission of historic medicinal, pharmaceutical, and cosmetic artifacts, increasing understanding of, and decision-making for, similar collections of objects. Eventually, it is hoped that this information can be used to inform mitigation strategies for the capture and reduction of VOCs in collections storage areas. In the experiment, the researchers used many compounds, for example, Ethyl 2-hydroxybenzoate (cas: 118-61-6Formula: C9H10O3).

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

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