Month: December 2022

Vereshchagin, Anatoly N. published the artcileHighly diastereoselective four-component synthesis of polysubstituted 1,4,5,6-tetrahydropyridines, Formula: C6H10O3, the publication is Chemistry of Heterocyclic Compounds (New York, NY, United States) (2021), 57(9), 929-933, database is CAplus.

A novel four-component diastereoselective synthesis of polysubstituted tetrahydropyridines (4SR,6RS)-I (R = H, 3-F, 4-Me, 4-Cl, etc.; R¹ = Me, Et, Ph, 4-bromophenyl; R² = Me, Et) is reported. The Michael addition – Mannich reaction – cyclization – dehydration cascade of benzylidenemalononitriles RC₆H₄CH=C(CN)₂, esters of 3-oxocarboxylic acids R¹C(O)CH₂C(O)OR², aromatic aldehydes RC₆H₄CHO, and ammonium acetate in methanol provides convenient access to 2-substituted alkyl (4SR,6RS)-4,6-diaryl-5,5-dicyano-1,4,5,6-tetrahydropyridine- 3-carboxylates (4SR,6RS)-I with two stereocenters in 66-92% yields. The formation of products was highly stereoselective, with only one diastereomer formed. Ammonium acetate plays dual role acting as a base and as a nitrogen source. The formation of single diastereomer was confirmed by singe crystal X-ray diffraction studies.

Chemistry of Heterocyclic Compounds (New York, NY, United States) published new progress about 30414-53-0. 30414-53-0 belongs to esters-buliding-blocks, auxiliary class Aliphatic hydrocarbon chain,Ketone,Ester, name is Methyl 3-oxovalerate, and the molecular formula is C8H17Br, Formula: C6H10O3.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Cheshmedzhieva, Diana published the artcileHydrogen bonding probes electron density variations at the basic center in substituted alkyl benzoates: Theory and experiment, Formula: C11H15NO2, the publication is Journal of Physical Organic Chemistry (2021), 34(11), e4258, database is CAplus.

Theor. computations of charge d. parameters are juxtaposed to exptl. spectroscopic shifts induced by hydrogen bonding for a series of 21 substituted in the aromatic ring Et and Me benzoates. Strong correlations between at. charges at the proton accepting atom and the shifts of methanol O-H frequencies are established. Hirshfeld, Charge Model 5 (CM5), and natural population anal. (NPA) at. charges are evaluated using ωB97X-D/6-311++G(3df,2pd) and MP2/6-311++G(3df,2pd) computations. The results obtained reveal the power of hydrogen bond measurements in characterizing the variations of electron densities at the proton accepting center within a series of structurally related mols. The limits of application of the approach are outlined.

Journal of Physical Organic Chemistry published new progress about 10287-53-3. 10287-53-3 belongs to esters-buliding-blocks, auxiliary class Amine,Benzene,Ester, name is Ethyl 4-dimethylaminobenzoate, and the molecular formula is C11H15NO2, Formula: C11H15NO2.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Kolarevic, Ana published the artcileSynthesis and DNase I inhibitory properties of some 4-thiazolidinone derivatives, Synthetic Route of 19788-49-9, the publication is Journal of Cellular Biochemistry (2019), 120(1), 264-274, database is CAplus and MEDLINE.

Twelve new thiazolidinones were synthesized and, together with 41 previously synthesized thiazolidinones, evaluated for inhibitory activity against DNase I (DNase I) in vitro. Ten compounds inhibited com. bovine pancreatic DNase I with an IC50 below 200 μM and showed to be more potent DNase I inhibitors than crystal violet (IC50 = 365.90 ± 47.33 μM), used as a pos. control. Moreover, three compounds were active against DNase I in rat liver homogenate, having an IC50 below 200 μM. (3-Methyl-1,4-dioxothiazolidin-2-ylidene)-N-(2-phenylethyl)ethanamide (41) exhibited the most potent DNase I inhibition against both com. and rat liver DNase I with IC50 values of 115.96 ± 11.70 and 151.36 ± 15.85 μM, resp. Site Finder and mol. docking defined the thiazolidinones interactions with the most important catalytic residues of DNase I, including the H-acceptor interaction with residues His 134 and His 252 and/or H-donor interaction with residues Glu 39 and Asp 168. The three most active compounds against both com. and rat liver DNase I (31, 38, and 41) exhibited favorable physico-chem., pharmacokinetic, and toxicol. properties. These observations could be utilized to guide the rational design and optimization of novel thiazolidinone inhibitors. Thiazolidinones as novel DNase I inhibitors could have potential therapeutic applications due to the significant involvement of DNase I in the pathophysiol. of many disease conditions.

Journal of Cellular Biochemistry published new progress about 19788-49-9. 19788-49-9 belongs to esters-buliding-blocks, auxiliary class Thiol,Aliphatic hydrocarbon chain,Ester, name is Ethyl 2-mercaptopropanoate, and the molecular formula is C5H10O2S, Synthetic Route of 19788-49-9.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Sharma, G. V. M. published the artcileA Mild and Highly Selective Deprotective Method of Prenyl Ethers Using Ytterbium Triflate, Quality Control of 5205-11-8, the publication is Journal of Organic Chemistry (1998), 63(24), 9103-9104, database is CAplus.

A study of the deprotection of prenyl ethers with a catalytic amount of Yb(O₃SCF₃)₃ as Lewis acid catalyst is decribed. Thus coumarin I (R = CH₂CH:CMe₂) was treated with catalytic Yb(O₃SCF₃)₃ in MeNO₂ to give I (R = H) in 60% yield.

Journal of Organic Chemistry published new progress about 5205-11-8. 5205-11-8 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Benzene,Ester, name is 3-Methylbut-2-en-1-yl benzoate, and the molecular formula is C7H6N2O2S, Quality Control of 5205-11-8.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Kiselevsky, Dmitry B. published the artcileInvestigation of the Antioxidant Properties of the Quaternized Chitosan Modified with a Gallic Acid Residue Using Peroxidase that Produces Reactive Oxygen Species, Quality Control of 121-79-9, the publication is Biochemistry (Moscow) (2022), 87(2), 141-149, database is CAplus and MEDLINE.

Chitosan modified with a (2-hydroxy-3-trimethylammonium) Pr group and gallic acid residue, or quaternized chitosan with gallic acid (QCG), was synthesized. Antioxidant properties of the produced QCG have been investigated. Peroxidase in combination with NADH and salicyl hydroxamate (SHAM) caused consumption of oxygen and production of H₂O₂ in aqueous solution as a result of O₂ reduction in the peroxidase-oxidase reactions. The rates of O₂ consumption and H₂O₂ generation were reduced in the presence of QCG. The antioxidant Pr gallate (PG) and superoxide dismutase (SOD) had the same effect, but not the quaternized chitosan (QC) without gallic acid. The effect of chitosan derivatives on the production of reactive oxygen species (ROS) in the cells of pea leaf epidermis and on the cell death detected by the destruction of cell nuclei, was investigated. The QCG, QC, and SOD had no effect, while PG decreased the rate of ROS generation in the cells of the epidermis, which was induced by NADH with SHAM or by menadione. The QCG and QC prevented destruction of the guard cell nuclei in the pea leaf epidermis that was caused by NADH with SHAM or by KCN. The SOD had no effect on the destruction of nuclei, while the effect of PG depended on the inducer of the cell death. Suppression of the destruction of guard cell nuclei by chitosan derivatives was associated not with their antioxidant effect, but with the disruption of the plasma membrane of the cells. The results obtained have shown that QCG exhibits antioxidant properties in solutions, but does not prevent generation of ROS in the plant cells. The mechanism of antioxidant effect of QCG is similar to that of PG and SOD.

Biochemistry (Moscow) published new progress about 121-79-9. 121-79-9 belongs to esters-buliding-blocks, auxiliary class Natural product, name is Propyl 3,4,5-trihydroxybenzoate, and the molecular formula is C10H12O5, Quality Control of 121-79-9.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Garrido-Gonzalez, Jose J. published the artcileAn Enzyme Model Which Mimics Chymotrypsin and N-Terminal Hydrolases, SDS of cas: 1877-71-0, the publication is ACS Catalysis (2020), 10(19), 11162-11170, database is CAplus.

Enzymes are the most efficient and specific catalysts to date. Although they have been thoroughly studied for years, building a true enzyme mimic remains a challenging and necessary task. Here, we show how a three-dimensional geometry anal. of the key catalytic residues in natural hydrolases has been exploited to design and synthesize small-mol. artificial enzymes which mimic the active centers of chymotrypsin and N-terminal hydrolases. The optimized prototype catalyzes the methanolysis of the acyl enzyme mimic with a half-life of only 3.7 min at 20 °C, and it is also able to perform the transesterification of vinyl acetate at room temperature DFT studies and X-ray diffraction anal. of the catalyst bound to a transition state analog proves the similarity with the geometry of natural hydrolases.

ACS Catalysis published new progress about 1877-71-0. 1877-71-0 belongs to esters-buliding-blocks, auxiliary class Carboxylic acid,Benzene,Ester, name is 3-(Methoxycarbonyl)benzoic acid, and the molecular formula is C9H8O4, SDS of cas: 1877-71-0.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Ohiri, Reginald C. published the artcileSolvent based variations in yield of bioactive extracts from the sclerotium of Pleurotus tuber-regium, Synthetic Route of 110-34-9, the publication is Chemica Sinica (2019), 10(1), 773-791, database is CAplus.

Background: The therapeutic effectiveness of herbs and fungi used for medicinal purposes is not only a factor of their bioactive constituents but also a factor of both the extraction solvent and extraction method. Objective: The objective of this study is to extract and analyze the bioactive components in the sclerotum of Pleurotus tuber-regium using different solvents, as to ascertain the solvent that gives a better yield. Method: A quantity of 10.0 kg of fresh sclerotia of P. tuber-regium purchased at Zarama Market in Southern Nigeria was washed, peeled and the white inner parts were sliced using a sterilized knife. The sliced samples were dried at room temperature for fourteen days. After grinding, the bioactive components were extracted by weighing 10 g of sample into three well stopper bottles and each was extracted in 20 mL of specific extraction solvent (methanol, hexane and dichloromethane), while that of soxleth extraction was done in a soxleth apparatus, using ethanol as the solvent. The process was repeated twice and the combined aliquot obtained were concentrated to 5.0 mL and purified. Two milliliters of the extracts were used for gas chromatog. and mass spectroscopy anal. Result: The highest peak on the chromatogram for the methanol extract was observed at 32.644 min., while hexane, dichloromethane and soxhlet extracts had their highest peaks at 31.459 min., 14.254 min. and 18.060 min. resp. The highest bioactive component in methanol extract was (3aR,4R,7R)-1,4,9,9-Tetramethyl-3, 4,5,6,7,8-hexahydro2H-3a,7-methane with a value of 62.856%, while hexane, dichloromethane and soxhlet extracts had Hexasiloxane, tetradecamethyl-, Bis(2-ethylhexyl) phthalate and Phthalic acid, 3-chlorobenzyl Bu ester with values of 29.170%, 5.092% and 25.490% resp. Conclusion: Hexane and dichloromethane extracts yielded more bioactive components with better nutriceutical and medicinal properties and may be regarded as better solvents for mushroom and fungi extractions.

Chemica Sinica published new progress about 110-34-9. 110-34-9 belongs to esters-buliding-blocks, auxiliary class Aliphatic hydrocarbon chain,Ester, name is Isobutyl palmitate, and the molecular formula is C20H40O2, Synthetic Route of 110-34-9.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Matsumoto, Fumio published the artcileVolatile components of Hedychium coronarium Koenig flowers, Computed Properties of 5205-11-8, the publication is Journal of Essential Oil Research (1993), 5(2), 123-33, database is CAplus.

The solvent extract and the headspace of Hedychium coronarium flowers were investigated by GC and GC/MS. A volatile concentrate of the solvent extract which was obtained by simultaneous distillation and extraction (SDE) was fractionated by column chromatog. and analyzed by GC and GC/MS. Of the 175 compounds identified, linalool, Me benzoate, cis-jasmone, eugenol, (E)-isoeugenol, jasmin lactone, Me jasmonate, Me epi-jasmonate, indole, nitriles and oximes were found to make a great contribution to the scent of the flowers. A total of 113 compounds were identified in the headspace. The daily and the seasonal changes of the odor characteristics of H. coronarium flowers were considered. Qual. differences of the volatiles obtained by thermal and solvent desorption of the headspace traps were also discussed.

Journal of Essential Oil Research published new progress about 5205-11-8. 5205-11-8 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Benzene,Ester, name is 3-Methylbut-2-en-1-yl benzoate, and the molecular formula is C12H14O2, Computed Properties of 5205-11-8.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Al-Awadi, Nouria A. published the artcileEnaminones in a multicomponent synthesis of 4-aryldihydropyridines for potential applications in photoinduced intramolecular electron-transfer systems, Quality Control of 924-99-2, the publication is Beilstein Journal of Organic Chemistry (2012), 441-447, database is CAplus and MEDLINE.

An efficient three component reaction with enaminones, primary amines and aldehydes resulted in easy access to 1,4-dihydropyridines with different substituents at the 1-, 3-, 4- and 5-positions. Microwaves improved the reaction yield, reducing also considerably the reaction time and the amount of solvent used. Chiral primary amines gave chiral 1-substituted-1,4-dihydropyridines. The 4-(1-naphthyl) and 4-(phenanthren-9-yl)dihydropyridine derivatives exhibited an interesting photoluminescence behavior, which suggests their potential application as suitable photoinduced intramol. electron-transfer systems.

Beilstein Journal of Organic Chemistry published new progress about 924-99-2. 924-99-2 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Amine,Aliphatic hydrocarbon chain,Ester, name is Ethyl 3-(dimethylamino)acrylate, and the molecular formula is C7H13NO2, Quality Control of 924-99-2.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Behbehani, Haider published the artcileSynthetic Strategy for Pyrazolo[1,5-a]pyridine and Pyrido[1,2-b]indazole Derivatives through AcOH and O₂-Promoted Cross-dehydrogenative Coupling Reactions between 1,3-Dicarbonyl Compounds and N-Amino-2-iminopyridines, Safety of Methyl 3-oxovalerate, the publication is ACS Omega (2019), 4(12), 15289-15303, database is CAplus and MEDLINE.

An efficient method has been developed for the synthesis of uniquely substituted pyrazolo[1,5-a]pyridine and pyrido[1,2-b]indazole derivatives, which involves acetic acid and mol. oxygen promoted cross-dehydrogenative coupling reactions of resp. β-ketoesters and β-diketones (like Et acetoacetate, Et benzoylacetate, Me propionylacetate, acetylacetone, dimedone, 1,3-cyclohexanedione, and 1,3-cyclopentanedione) with N-amino-2-iminopyridines. The proposed tentative mechanism involves formal acetic acid-promoted oxidative C(sp³)-C(sp²) dehydrogenative coupling followed by dehydrative cyclization under a catalyst-free condition within high atom economy processes.

ACS Omega published new progress about 30414-53-0. 30414-53-0 belongs to esters-buliding-blocks, auxiliary class Aliphatic hydrocarbon chain,Ketone,Ester, name is Methyl 3-oxovalerate, and the molecular formula is C6H10O3, Safety of Methyl 3-oxovalerate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics