Synthesis of 1-Palmitoyl-2-((E)-9- and (E)-10-nitrooleoyl)-sn-glycero-3-phosphatidylcholines

Synthesis ◽  
2019 ◽  
Vol 51 (17) ◽  
pp. 3295-3304
Author(s):  
Alexander Lehr ◽  
Andrea Frank ◽  
Winfried Münch ◽  
Ulrich Dietz ◽  
Udo Nubbemeyer

Extensive investigation of nitrated phospholipids in connection with various biologically important processes requires reliable access to suitable material. A selective chemical synthesis introducing a defined nitrofatty acid at the sn-2 position of a 2-lyso sn-glycero-3-phosphatidylcholine was developed. Given that the nitroalkene moiety of both reactant nitrofatty acid derivative and the product esters is characterised by particular sensitivity to nucleophile addition and, depending on the intermediate, subsequent olefin isomerisation and retro-Henry-type reaction, a reliable two-step ester formation was introduced. The activation of the nitrofatty acid succeeded after reaction with trichlorobenzoyl chloride, and the mixed anhydride could be isolated via extractive work-up. Subsequent reaction with 1-palmitoyl-2-lyso-sn-glycero-3-phosphatidylcholine enabled the sn-2 esterification to be achieved with high yield by using a minimum of reagents, avoiding the formation of side products and facilitating final isolation and purification.

2020 ◽  
Vol 17 (9) ◽  
pp. 709-716
Author(s):  
Ebrahim Saeedian Moghadam ◽  
Shahrzad Ghafary ◽  
Mohsen Amini

With regard to the importance of quinazoline as a privileged scaffold, herein we report the synthesis of twenty seven 2,4-disubstitute quinazoline derivatives in a new catalyst free condition. In the current work, poly ethylene glycol (PEG1000) as an inexpensive, very simple commercially available, ecofriendly and low melting point solvent was used. Air bubbling, a green oxidant, for oxidation purpose was also used. This is the first report about using PEG1000 as a solvent simultaneously with air bubbling as oxidant in quinazoline synthesis. All of the compounds 1-27 were synthesized in high yield with very simple work up and purification process without using column chromatography. All the structures were confirmed using 1H NMR, 13C NMR, IR, MS and elemental analysis.


2020 ◽  
Vol 17 (8) ◽  
pp. 654-660
Author(s):  
Shermineh Sadat Ghalehbandi ◽  
Dadkhoda Ghazanfari ◽  
Sayed Ali Ahmadi ◽  
Enayatollah Sheikhhosseini

Introduction: We developed a simple, fast and new method for the Fries rearrangement of aryl esters. Materials and Methods: 4-Hydroxy pyridinium triflate functionalized silica is a very efficient, reusable and economically available catalyst for the Fries rearrangement in solvent-free condition and under microwave irradiation. Results and Discussion: Also, a notable selectivity was observed in the presence of 4-hydroxy pyridinium triflate functionalized silica. Conclusion: Selectivity, shorter reaction time, high yield, and easy work-up are advantages of this synthetic method.


Organics ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 17-25
Author(s):  
Wenhong Lin ◽  
Shea T. Meyer ◽  
Shawn Dormann ◽  
John D. Chisholm

2-(Trimethylsilyl)ethyl 2,2,2-trichloroacetimidate is readily synthesized from 2-trimethylsilylethanol in high yield. This imidate is an effective reagent for the formation of 2-trimethylsilylethyl esters without the need for an exogenous promoter or catalyst, as the carboxylic acid substrate is acidic enough to promote ester formation without an additive. A deuterium labeling study indicated that a β-silyl carbocation intermediate is involved in the transformation.


2016 ◽  
Vol 5 (4) ◽  
Author(s):  
Ramadan Ahmed Mekheimer ◽  
Abdullah Mohamed Asiri ◽  
Afaf Mohamed Abdel Hameed ◽  
Reham R. Awed ◽  
Kamal Usef Sadek

AbstractStarting from readily available 2-naphthol, aldehydes, aryl and alkylamines, a variety of Betti bases were efficiently synthesized utilizing a catalytic amount of cerium (IV) ammonium nitrate (CAN) at room temperature. This protocol has advantages of high yield, mild reaction conditions, no environmental pollution, diversity of reactants and simple work up procedure.


2017 ◽  
Vol 41 (2) ◽  
pp. 75-78
Author(s):  
Yulan Ren ◽  
Hang Song

A series of sixteen 2,2′-(arylmethylene)bis(3-hydroxy-6-methyl-4H-pyran-4-ones) have been prepared in high yield via an ammonium acetate-catalysed three-component reaction of an aromatic aldehyde (1 equiv.) and allomaltol (2 equiv.) in an ionic liquid [bmim+][BF4–]. The reaction work-up is simple and the ionic liquid can be easily separated from the product and reused.


2019 ◽  
Vol 140 ◽  
pp. 02007
Author(s):  
Larisa Popova ◽  
Anzhelika Tsyrulnikova ◽  
Sergey Vershilov ◽  
Julia Bazarnova ◽  
Ekaterina Aronova ◽  
...  

Based on the unsaturated derivatives of polyfluoroalkanols chemical products are used to protect solid and fibrous materials surface from the effects of water, oils and other pollutants. A method for obtaining allyl ethers of polyfluoroalkanols (polyfluoroalkoxypropenes) is based on the Williamson ether reaction. This method is a heterophase process. The use of solvents to improve mass transfer requires complementary measures to ensure industrial and environmental safety. It is more preferable to obtain the target ethers in water with PTC. A series of experiments using different chain length polyfluoroalkanols was studied by GLC. Kovats retention indexes of the target ethers were determined. It was found that in the case of lower homologues (CF3CH2OH, (CF3)2CHOH, HCF2CF2CH2OH), the addition of 5-15 vol.% 1,4-dioxane as a solubilizer provides a high yield of products. The application of PTC (tetrabutylammonium bromide) is indispensable for using polyfluoroalkanols with a longer carbon chain (C≥5). PTC invariably provides the almost complete conversion of polyfluoroalkanols. The decomposition process of TBAB becomes noticeable (GLC method) upon completion of the main reaction. Polyfluoroalkoxypropenes form azeotrope with water, which can be used in the work up process.


2019 ◽  
Vol 31 (4) ◽  
pp. 829-833
Author(s):  
D.S. Bhagat ◽  
S.G. Pande ◽  
M.V. Katariya ◽  
R.P. Pawar ◽  
P.S. Kendrekar

One-pot efficient protocol to the synthesis of 2-amino-5-oxo-4,5-dihydropyrano(3,2-c)chromene-3-carbonitrile derivatives via condensation of various aryl aldehydes, dicyanomethane and 4-hydroxycoumarin in presence of Emim hydroxide as an excellent homogeneous liquid catalyst. The key advantages of this methodology are mild reaction conditions, novel catalyst, short reaction time, eco-friendly, easy work-up procedure and high yield of isolation of derivatives.


1952 ◽  
Vol 5 (4) ◽  
pp. 728
Author(s):  
JM Swan

Linear anhydrides are formed by the action of acetic anhydride on p-toluene-sulphonylglycine and carbobenzyloxy-glycine, -phenylalanine, and -β-alanine. The anhydrides from the first two acids yield the corresponding 2-thiohydantoin with ammonium thiocyanate in acetic acid. Other methods for the preparation of l-p-toluenesulphonylglycine anhydride, and its 2-thiohydantoin, are also given. Hippuric acid, with ethyl chlorocarbonate and triethylamine yields ethyl hippurate, probably via the mixed anhydride and 2-phenyloxazol-5-one. The inclusion of ammonium thiocyanate gives 1-benzoyl-2-thiohydantoin in high yield. The N-carboxy anhydride of phenylalanine (4-benzyloxazolid-2,5-dione) also reacts with ammonium thiocyanate to give carbon dioxide and 5-benzyl-2-thiohydantoin.


Piperine was discovered in 1819 by Hans Christian, who isolated it from the fruits of Piper nigrum, the source plant of both the black and white pepper grains [1]. Fluckiger and Hanbury found piperine in Piper longum and Piper officinarum Piperine, along with its isomer chavicine, is the alkaloid[1b] responsible for the pungency of black pepper and long pepper [2]. Piperine is extracted from black pepper using dichloromethane [3]. Aqueous hydrotropes can be used in the extraction to result in high yield and selectivity [4]. The amount of piperine varies from 1-2% in long pepper, to 5-10% in commercial white and black peppers [5]. Further, it may be prepared by treating the solvent-free residue from an alcoholic extract of black pepper, with a solution of potassium hydroxide to remove resin (said to contain chavicine, an isomer of piperine) and solution of the washed, insoluble residue in warm alcohol, from which the alkaloid crystallises on cooling [6]. It has been used in some forms of traditional medicine. Piperine, a major alkaloid in black pepper is one of the most gifted bioenhancers till date. Additional methods used for its isolation suffer disadvantages such as poor extraction efficiency, tedious and pricey isolation methodology, piperine photode gradation, etc. Hence a simple, rapid and well-organized method has been developed for the extraction of piperine from the fruits of Piper nigrum. The methods under study involve extraction of piperine with various solvents such as ethanol, propionic acid and dichloromethane. Then isolation and purification were followed by separate classical methods for respective extracts. Compared to other two methods, the novel method using propionic acid proved to be valuable in isolating piperine with higher yield and in higher purity. Hence extract derived using propionic acid was further subjected to alkali wash and passing out through small silicagel bed. Then identification of the compound was confirmed by various analytical methods TLC, melting point, UV-visible spectrophotometer, FT-IR, HPLC and compared it with authentic piperine which resulted into better pure piperine crystals as that of authentic piperine.


Author(s):  
Rameshwar R. Magar ◽  
Ganesh T. Pawar ◽  
Sachin P. Gadekar ◽  
Machhindra Karbhari Lande

The Ce-ZSM-11 zeolite has been used as an efficient catalyst for the one pot synthesis of 1,8-dioxo-octahydroxanthene derivatives from aromatic aldehyde and 5,5-dimethyl-cyclohexane-1,3-dione under reflux condition. The catalyst was characterized by Powder X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmer-Teller (BET) surface area analysis, and Temperature Programmed Desorption (TPD) techniques. This method provides several advantageous such as use of inexpensive catalyst, simple work-up procedure, high yield of desired product and reusability of catalyst. Copyright © 2018 BCREC Group. All rights reservedReceived: 5th January 2018; Revised: 25th May 2018; Accepted: 27th May 2018How to Cite: Magar, R.R., Pawar, G.T., Gadekar, S.P., Lande, M.K. (2018). An Efficient Synthesis of  1,8-Dioxo-Octahydroxanthenes Derivatives Using Heterogeneous Ce-ZSM-11 Zeolite Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 436-446 (doi:10.9767/bcrec.13.3.2062.436-446)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2062.436-446 


Sign in / Sign up

Export Citation Format

Share Document