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An Overview of Helminthiasis
Published in Venkatesan Jayaprakash, Daniele Castagnolo, Yusuf Özkay, Medicinal Chemistry of Neglected and Tropical Diseases, 2019
Leyla Yurttaș, Betül Kaya Çavușoğlu, Derya Osmaniye, Ulviye Acar Çevik
Levamisole (11) is a large-spectrum anthelmintic agent that is effective against ascardiasis and hookworm infections. It is a nicotinic receptor agonist and lead to spastic paralysis. The side effects of levamisole are mild and include nausea, headache, dizziness, skin rash and gastrointestinal disturbance. For the synthesis of levamisole, styrene oxide is initially reacted with ethanolamine followed by subsequent replacement of the hydroxyl groups using thionyl chloride to give 2-chloro-N-(2-chloroethyl)-2- phenylethan-1-amine. Acidic hydrolysis followed by reaction with thiourea led to a thiazolidine ring. The reaction of the latter molecule with thionyl chloride and alkaline treatment affords the racemic tetramizol, which is in turn separated into its dextro- and levo-isomers. Levamisole is the levo isomer of tetramizol (Akgün et al. 2013). The synthesis of Levamisole (11).
Chemical Weapons Holdings and Their Internationally Verified Destruction
Published in Brian J. Lukey, James A. Romano, Salem Harry, Chemical Warfare Agents, 2019
Libya is currently implementing, with EU financial support, an environmental survey and cleanup project at the Ruwagha site. Environmental problems stem from the incineration and hydrolysis products of pre-2016 sulfur mustard destruction operations (which possibly comprise several metric tons of contaminated salts). In addition, a number of the older tanks filled with phosphorus trichloride and thionyl chloride were badly corroded and probably leaked. Russia has requested the OPCW to report on the discrepancy between declared chemicals at the Ruwagha site and the amounts shipped to GEKA in 2016. These destruction operations were completed in January 2018 (Federal Foreign Office (Germany), “Vernichtung von Restbeständen des libyschen Chemiewaffenprogramms in Deutschland erfolgreich beendet” [Successful completion of the destruction in Germany of the remnants of Libya’s chemical weapon program], Press release, 5 January 2018, www.auswaertiges-amt.de/de/newsroom/libysche-chemiewaffen/1210838).
Chemistry
Published in Stephen P. Coburn, The Chemistry and Metabolism of 4′-Deoxypyridoxine, 2018
Muhlradt and Snell348 and Korytnyk et al.253 both used alpha4-3-O-isopropylidene pyridoxine to protect the 3 and 4′-positions. The 5′-position was then chlorinated with thionyl chloride followed by hydrogenation and hydrolysis. The procedure was also presented in detail by Korytnyk and Ikawa.251 We have used the latter procedure successfully with the exception that we found it necessary to reflux the thionyl chloride reaction for 2 hr in order to get a satisfactory yield of the chloride.
Novel positive allosteric modulators of A2B adenosine receptor acting as bone mineralisation promoters
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2021
Elisabetta Barresi, Chiara Giacomelli, Laura Marchetti, Emma Baglini, Silvia Salerno, Giovanni Greco, Federico Da Settimo, Claudia Martini, Maria Letizia Trincavelli, Sabrina Taliani
An excess of thionyl chloride (0.28 ml, 3.86 mmol) was added at 0 °C to a suspension of the acids 18-20 (1.93 mmol) in dry toluene (2 ml). The mixture was refluxed for 3 h and then the excess of thionyl chloride was distilled off under reduced pressure and the residue was washed three times with dry toluene. The oily residue obtained was dissolved in 10 ml of anhydrous THF, cooled at 0 °C and added with triethylamine (0.29 ml, 2.12 mmol). Then, a solution of the appropriate amine (benzylamine for 8 and 10, 4-chlorobenzylamine for 9, 1.93 mmol) in 2 ml of dry THF was added. The reaction mixture was left under stirring at room temperature for 24–48 h (TLC analysis; petroleum ether 60–80 °C/ethyl acetate in ratio 7:3 as eluting system). After filtering off the triethylamine hydrochloride, the solution was concentrated to dryness. The residue was triturated with diluted hydrochloric acid and then with saturated sodium hydrogen carbonate aqueous solution, washed with water and collected to give a crude product, which was purified by recrystallization from the appropriate solvent.
Can nanotechnology help in the fight against COVID-19?
Published in Expert Review of Anti-infective Therapy, 2020
Gabriela Palestino, Ileana García-Silva, Omar González-Ortega, Sergio Rosales-Mendoza
Baneerjee et al. [74] prepared multi-walled carbon nanotubes (MWNT) functionalized with protoporphyrin (PPIX) as material (NT-P) to reduce the ability of the Influenza A virus to infect mammalian cells. The virus tested was the influenza strain X-31, A/Aichi/2/68 (H3N2), while the cells analyzed was the pulmonary mucoepidermoid carcinoma cell line NCI-H292 (ATCC# CRL-1848). The material was generated by first preparing acid-functionalized MWNT and aminated PPIX. They were afterward reacted in the presence of thionyl chloride. When treating NCI cells with NT-P in the presence of virus following 90 min of light irradiation, the percentage of infection was reduced to 1% (78% of percentage infection was achieved when the system was in the dark). This situation was ascribed to the production of ROS by PPIX in the presence of light and not the MWNT. As expected photobleaching is a major concern of the NT-P material, while reusability studies indicated that the material could be used five times. The authors envisioned this material as a disinfectant of surfaces and water; moreover, it has the characteristics of simple recovery and non-toxicity in terms of the generated byproducts. Furthermore, since the system is based on the generation of ROS (that induces protein oxidation, breakage in the RNA genome, and protein-RNA crosslinking) [75], it can be expected to function with all influenza virus strains.
Synthesis and characterization of PEG-functionalized graphene oxide as an effective pH-sensitive drug carrier
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Mohamad Kazempour, Hassan Namazi, Abolfazl Akbarzadeh, Roya Kabiri
Graphite was purchased from Sigma-Aldrich, and it was used without further purification. Several analytical grades of polyethylene glycols (PEG), H2SO498%, H2O230wt%, NaNO3, sodium sulphate (Na2SO4), KMnO4 were obtained from Merck Co. Ltd, Germany. Thionyl chloride (SOCl2), was purchased from Sigma-Aldrich (Saint Louis, MO). Hydrochloric acid (HCl), nitric acid (HNO3), anhydrous tetrahydrofuran (THF) and anhydrous N,N-dimethylformamide (DMF) were purchased from Fisher Scientific (Pittsburgh). THF and DMF were dried over CaH2 before use. Doxorubicin hydrochloride (DOX) was purchased from EBEWE Pharma Co. Ltd. A dialysis chamber for the drug release was purchased from Sigma-Aldrich (Saint Louis, MO).