1193-92-6Relevant articles and documents
Isoxazoles: Synthesis, evaluation and bioinformatic design as acetylcholinesterase inhibitors
Gutiérrez, Margarita,Matus, María Francisca,Poblete, Tomas,Amigo, Jessica,Vallejos, Gabriel,Astudillo, Luis
, p. 1796 - 1804 (2013)
Objectives Inhibition of acetylcholinesterase (AChE) is a common treatment for early stages of Alzheimer's disease. In this study, nine isoxazoles derivatives were tested for their in-vitro AChE activity. The molecular docking showed the interaction of the compounds with the active site. Methods The isoxazoles were synthesized using 1,3-dipolar cycloaddition in the presence of sodium hypochlorite. They were also isolated and characterized by spectroscopic methods. The in-vitro activity was measured by an adapted version of Ellman's assay. Key findings The isoxazoles are described as inhibitors of AChE. The most potent compound in the series exhibited a moderate inhibitory activity (50% inhibitory concentration = 134.87 μm). The design of new compounds was created by using the RACHEL module of the SYBYL software. Conclusions Our research provided enough evidence of the efficacy of isoxazoles as AChE inhibitors. The isoxazoles were synthesized and evaluated as inhibitors of AChE. The docking study based on a novel series of complexes isoxazole with AChE from Electroporus electricus has demonstrated that the ligand bind is similar to the compounds used as reference. To find new candidates with the isoxazole core that act as inhibitors of AChE, part of the structure of the compound 9 was used for de-novo design. Molecular docking models of the ligand-AChE complexes suggest that the compound 10 is located on the periphery of the AChE active site.
AN IMPROVED PROCESS FOR PREPARATION OF PURE ALDOXIME
-
Page/Page column 14-15, (2021/06/22)
The present invention relates to an improved process for preparing aldoximes of formula (I) with high purity and high yield. The improved process for preparing aldoxime is fast, simple, highly efficient, and reproducible. The improved process for the preparation of aldoxime, which is synthesized in the higher yield under oximation reaction of aldehyde with hydroxylamine hydrochloride merely in aqueous medium using of in situ heat generation.
Electrochemical synthesis of 1,2,4-oxadiazoles from amidoximes through dehydrogenative cyclization
Hu, Aixi,Jiang, chan,Li, mingfang,Xu, Leitao,Ye, Jiao,Yi, Yangjie
supporting information, p. 10611 - 10616 (2021/12/27)
A convenient and efficient method for the generation of the iminoxy radical through anodic oxidation was developed for the synthesis of 3,5-disubstituted 1,2,4-oxadiazoles fromN-benzyl amidoximes. The transformation proceeds through 1.5-Hydrogen Atom Transfer (1,5-HAT) and intramolecular cyclization. The process features simple operation, mild conditions, broad substrate scope and high functional group compatibility, and provides a facile and practical way for the preparation of 1,2,4-oxadiazoles.
PROCESS FOR REGENERATING A LIQUID ABSORBENT
-
, (2020/11/12)
The invention provides a process for regenerating a liquid absorbent, comprising: contacting the liquid absorbent with a hydrophobic medium, wherein the liquid absorbent comprises at least one amine of Formula (I) and degradation product thereof comprising at least one imine of Formula (II), wherein each Ar is independently an aromatic group and each R is independently selected from hydrogen, an organyl group and NH2; and selectively extracting the degradation product into or through the hydrophobic medium.
1,3-Dipolar Cycloaddition, HPLC Enantioseparation, and Docking Studies of Saccharin/Isoxazole and Saccharin/Isoxazoline Derivatives as Selective Carbonic Anhydrase IX and XII Inhibitors
D'Ascenzio, Melissa,Secci, Daniela,Carradori, Simone,Zara, Susi,Guglielmi, Paolo,Cirilli, Roberto,Pierini, Marco,Poli, Giulio,Tuccinardi, Tiziano,Angeli, Andrea,Supuran, Claudiu T.
, p. 2470 - 2488 (2020/03/31)
Two series of saccharin/isoxazole and saccharin/isoxazoline hybrids were synthesized by 1,3-dipolar cycloaddition. The new compounds showed to be endowed with potent and selective inhibitory activity against the cancer-related human carbonic anhydrase (hCA) IX and XII isoforms in the nanomolar range, while no affinity was encountered for off-targets, such as hCA I and II. Successive enantioseparation on a milligram scale of the most representative compounds led to the discovery that (S)-isomers were more potent than their corresponding (R)-enantiomers. Lastly, molecular modeling studies were conducted to define those structural requirements that were responsible for the discrimination among selected human isoforms of carbonic anhydrases. Two nanomolar hCA IX and XII inhibitors were also screened for their selective toxicity against non tumoral primary cells (fibroblasts) and against a breast adenocarcinoma cell line (MCF7) in hypoxic environment. The efficacious combination of these compounds with doxorubicin on MCF7 cells was demonstrated after 72 h of treatment.
Chlorotropylium Promoted Conversions of Oximes to Amides and Nitriles
Xu, Jiaxi,Gao, Yu,Li, Zhenjiang,Liu, Jingjing,Guo, Tianfo,Zhang, Lei,Wang, Haixin,Zhang, Zhihao,Guo, Kai
, p. 311 - 315 (2020/01/25)
Chlorotropylium chloride as a catalyst for the transformations of oximes, ketones, and aldehydes to their corresponding amides and nitriles in excellent yields (up to 99 %) and in short reaction times (mostly 10–15 min). Oximes were electrophilically attacked on the hydroxyl oxygen by chlorotropylium. The produced tropylium oxime ethers were the key intermediates, of which the ketoxime ether led to amide through Beckmann rearrangement, and the aldoxime ether led to nitrile by nitrogen base DBU assisted formal dehydration. This chlorotropylium activation protocol offered general, mild, and efficient avenues bifurcately from oximes to both amides and nitriles by one organocatalyst.
Synthetic method for nicotinamide
-
Sheet 0028; 0029; 0031; 0032; 0034; 0035, (2018/09/11)
The invention belongs to the field of organic chemistry, and discloses a synthetic method for nicotinamide. The method comprises the following steps: using ethanol as a solvent, using 3-methylpyridineas a raw material, introducing a dried nitrosyl chloride gas, performing a photonitrosation-isomerization reaction under irradiation of visible light at temperature of 0-30 DEG C, after the reactionis completed, introducing a nitrogen gas, adding an alkali to adjust pH of the reaction solution to be 6-9, and performing filtration to obtain a filtrate; and adding a copper salt and a nitrile intothe filtrate as a catalyst, performing heating, performing reflux, performing an aldoxime Beckmann rearrangement reaction, after the reaction is completed, adding ethyl acetate crystals into the reaction solution, performing filtration to obtain a crude product of the nicotinamide, and performing recrystallization on the crude product of the nicotinamide to obtain a pure product of the nicotinamide. The synthetic method provided by the invention has mild reaction conditions, a simple process and a high yield, can obtain the high-purity nicotinamide product, has less three waste (waste water, waster gas and solid waste) and high economy, and is suitable for industrialized large-scale production.
Synthesis and biological evaluation of (3-arylisoxazol-5-yl)methyl 6-fluoro-4-oxo-4H-chromene-2-carboxylates as antioxidant and antimicrobial agents
Battula, Kumaraswamy,Narsimha, Sirassu,Nagavelli, Vasudeva Reddy,Rao, Mutheneni Srinivasa
, p. 1 - 12 (2017/02/15)
A series of novel (3-arylisoxazol-5-yl)methyl 6-fluoro-4-oxo-4H- -chromene-2-carboxylate derivatives (C1-C12) were synthesized by the Cu(I)- -catalyzed reaction of in situ generated nitrile oxides with prop-2-ynyl 6-fluoro- 4-oxo-4H-chromene-2-carboxylate in good yields and their antioxidant and antimicrobial activities were investigated. Among all the synthesized compounds, C1 (IC50: 16.43±0.57 μM) and C12 (IC50:15.98±0.72 μM) registered good antioxidant activity as compared to the standard drug trolox. Compounds C1, C3 and C6 registered very good inhibition against all the tested Gram-positive and Gram-negative bacterial strains with MIC values ranging from 9.375 to 37.5 μg mL-1. Compounds C7-C11 registered good inhibition against Bacillus subtilis and Staphylococcus aureus with MIC values ranging from 18.75 to 37.5 μg mL-1. Compounds C10 and C11 against Pseudomonas aeroginosa showed more prominent activity than the standard drug penicillin (MIC: 12.5 μg mL-1) with an MIC value of 9.375 μg mL-1 (≈ 1.33-fold more potent than penicillin). Compounds C7-C9 registered good to moderate antifungal activity against the four tested fungal strains with MIC values ranging from 18.75 to 37.5 μg mL-1.
Catalytic Enantioselective [3 + 2] Cycloaddition of α-Keto Ester Enolates and Nitrile Oxides
Bartlett, Samuel L.,Sohtome, Yoshihiro,Hashizume, Daisuke,White, Peter S.,Sawamura, Miki,Johnson, Jeffrey S.,Sodeoka, Mikiko
supporting information, p. 8661 - 8666 (2017/07/06)
An enantioselective [3 + 2] cycloaddition reaction between nitrile oxides and transiently generated enolates of α-keto esters has been developed. The catalyst system was found to be compatible with in situ nitrile oxide-generation conditions. A versatile array of nitrile oxides and α-keto esters could participate in the cycloaddition, providing novel 5-hydroxy-2-isoxazolines in high chemical yield with high levels of diastereo- and enantioselectivity. Notably, the optimal reaction conditions circumvented concurrent reactions via O-imidoylation and hetero-[3 + 2] pathways.
Asymmetric Nitrone Synthesis via Ligand-Enabled Copper-Catalyzed Cope-Type Hydroamination of Cyclopropene with Oxime
Li, Zhanyu,Zhao, Jinbo,Sun, Baozhen,Zhou, Tingting,Liu, Mingzhu,Liu, Shuang,Zhang, Mengru,Zhang, Qian
supporting information, p. 11702 - 11705 (2017/09/07)
We report realization of the first enantioselective Cope-type hydroamination of oximes for asymmetric nitrone synthesis. The ligand promoted asymmetric cyclopropene "hydronitronylation" process employs a Cu-based catalytic system and readily available starting materials, operates under mild conditions and displays broad scope and exceptionally high enantio- and diastereocontrol. Preliminary mechanistic studies corroborate a CuI-catalytic profile featuring an olefin metalla-retro-Cope aminocupration process as the key C-N bond forming event. This conceptually novel reactivity enables the first example of highly enantioselective catalytic nitrone formation process and will likely spur further developments that may significantly expedite chiral nitrone synthesis.
