876-02-8Relevant academic research and scientific papers
Preparation method for 4-methoxy-1,3-phthalic acid
-
Paragraph 0039; 0040; 0041; 0042, (2017/12/04)
The invention provides a preparation method for 4-methoxy-1,3-phthalic acid. 4-methoxy-1,3-phthalic acid is key intermediate for preparation of an anti-platelet aggregation drug picotamide (with a trade name of plactidil). According to the preparation method, 4-methoxy-1,3-phthalic acid is prepared from the starting raw material p-methylphenol or o-methylphenol through esterification, Fries rearrangement, methylation, oxidation and acidification. Compared with traditional preparation methods, the preparation method provided by the invention has the advantages of low equipment investment, simple operation, quick reaction, high yield, low synthesis cost, greatly reduced environmental pollution and the like, and is particularly suitable for large-scale industrial production.
Submicron ZnO raspberries as effective catalysts for Fries rearrangement
Ali, Mohammed,Rahaman, Hasimur,Pal, Sudip Kumar,Kar, Nikita,Ghosh, Sujit Kumar
, p. 41780 - 41785 (2015/05/27)
o-Xylene-in-water emulsion droplets have been exploited as soft templates for the synthesis of submicrometer-sized raspberry-like ZnO morphologies. The optical properties, structure and morphology of the microstructures have been characterised by absorption and fluorescence spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction and selected area electron diffraction analysis. It has been found that the microstructures could act as an environmentally benign and cost-effective alternative to conventional Lewis acid catalysts for the illustrious Fries rearrangement of o-methylphenyl acetate to 3-methyl-4-hydroxyacetophenone, employed as the model reaction and which has been probed by NMR spectroscopic studies.
Investigation on the substitution effects of the flavonoids as potent anticancer agents: A structure-activity relationships study
Wang, Xiao-Bing,Yang, Lei,Kong, Ling-Yi,Liu, Wei,Guo, Qing-Long
, p. 1833 - 1849,17 (2020/07/30)
Three series of flavonoid analogues substituted with different aminomethyl substitutions at C-6, C-7, and C-8 were designed and synthesized for the structure-activity relationship studies as potent anticancer agents. The prepared analogues were evaluated for their in vitro inhibitory activity against the growth of the hepatic cancer cell lines HepG2 and SMMC-7721. Structure-activity relationships indicated that not only the compounds with amino methyl groups were more active than those without the groups in the same series but also the compounds substituted by aminomethyl groups at position C-8 were more active than those at positions C-6 and C-7.
The phase change storage element and its manufacturing method
-
, (2007/10/10)
Disclosed are a phase change RAM device and a method for fabricating a phase change RAM device, which can efficiently lower intensity of current required for changing a phase of a phase change layer. The method includes the steps of providing a semiconductor substrate formed with an insulating interlayer including a tungsten plug, forming a first oxide layer on the semiconductor substrate, forming a pad-type bottom electrode, which makes contact with the tungsten plug, in the first oxide layer, forming a second oxide layer on the first oxide layer including the bottom electrode, and forming a porous polystyrene pattern on the second oxide layer such that a predetermined portion of the second oxide layer corresponding to a center portion of the bottom electrode is covered with the porous polystyrene pattern.
Effect of structurally constrained oxime-ether linker on PPAR subtype selectivity: Discovery of a novel and potent series of PPAR-pan agonists
Makadia, Pankaj,Shah, Shailesh R.,Pingali, Harikishore,Zaware, Pandurang,Patel, Darshit,Pola, Suresh,Thube, Baban,Priyadarshini, Priyanka,Suthar, Dinesh,Shah, Maanan,Giri, Suresh,Trivedi, Chitrang,Jain, Mukul,Patel, Pankaj,Bahekar, Rajesh
experimental part, p. 771 - 782 (2011/03/18)
A novel series of thaizole and oxazole containing phenoxy acetic acid derivatives is reported as PPAR-pan agonists. Incorporation of structurally constrained oxime-ether based linker in the chemotype of a potent PPARδ selective agonist GW-501516 was adapted as designing strategy. In vitro, selected test compounds 12a, 12c, 17a and 18a showed PPAR-pan agonists activities and among these four compounds tested, 12a emerged as highly potent and efficacious compound, while 17a exhibited moderate and balanced PPAR-pan agonistic activity. In vivo, selected test compounds 12a and 17a exhibited significant anti-hyperglycemic and anti-hyperlipidemic activities in relevant animal models. These results support our hypothesis that the introduction of structurally constrained oxime-ether linker between lipophilic tail and acidic head plays an important role in modulating subtype selectivity and subsequently led to the discovery of potent PPAR-pan agonists.
Improved alkylation and product stability in phosphotriester formation through quinone methide reactions with dialkyl phosphates
Bakke, Brian A.,McIntosh, Matthias C.,Turnbull, Kenneth D.
, p. 4338 - 4345 (2007/10/03)
Investigating reactions of functionalized p-quinone methides continues to advance our design of a reagent being developed for controlled, in situ modification of DNA via phosphodiester alkylation. Previously reported investigations of p-quinone methides derived from catechols allowed for trapping of isolable trialkyl phosphates for characterization and mechanistic information. However, lactone formation with these derivatives required long reaction times, resulting in an unfavorable mixture of trialkyl phosphate and hydrolysis products. To enhance the rate and efficacy of trialkyl phosphate formation and trapping, a phenol derived p-quinone methide has been designed to enforce a conformation favoring lactonization of the dialkyl phosphate alkylated intermediate. The relative rates of phosphodiester alkylation and subsequent trapping of the phosphotriester adduct have been examined by UV and 1H NMR analysis for p-quinone methide precursor 1 and the corresponding control, 1′. The incorporation of a methyl group at the meta-position of 1 (relative to 1′) significantly improves the rate of lactionization to provide a much higher yield of the desired product, lactonized phosphotriester 5. The control reaction with 1′ afforded only a minor amount of the corresponding lactonized trialkyl phosphate 5′.
Selective fries rearrangement catalyzed by zinc powder
Paul, Satya,Gupta, Monika
, p. 1789 - 1792 (2007/10/03)
Zinc powder in the presence of N,N-dimethylformamide efficiently catalyzes the selective Fries rearrangement of acetylated phenols under microwave heating or with conventional heating using an oil bath. In some cases different products were obtained using microwave heating and conventional heating. Selective migration of the acyl group has been noted with good yields.
2-aminopyridine derivatives and combinatorial libraries thereof
-
, (2008/06/13)
The present invention relates to novel 2-aminopyridine derivative compounds of the following formula: wherein R1to R5have the meanings provided herein. The invention further relates to combinatorial libraries containing two or more such compounds, as well as methods of preparing 2-aminopyridine derivative compounds.
Alumina in Methanesulfonic Acid (AMA) as a New Efficient Reagent for Direct Acylation of Phenol Derivatives and Fries Rearrangement. A Convenient Synthesis of o-Hydroxyarylketones
Sharghi, Hashem,Kaboudin, Babak
, p. 2678 - 2695 (2007/10/03)
Alumina in methanesulfonic acid (AMA) is used to prepare o-hydroxyaryl ketones by acylation of phenol and naphthol derivatives with carboxylic acids and the Fries rearrangement of phenolic esters. Mechanistic studies show that the acylation reaction in AMA occurred through an esterification followed by a Fries rearrangement of the phenolic ester by an intermolecular mechanism.
