scholarly journals The Underlying Chemistry to the Formation of PO 2 Radicals from Organophosphorus Compounds: A Missing Puzzle Piece in Flame Chemistry

2020 ◽  
Vol 26 (47) ◽  
pp. 10795-10800 ◽  
Author(s):  
Shuyu Liang ◽  
Patrick Hemberger ◽  
Mathias Steglich ◽  
Pietro Simonetti ◽  
Joëlle Levalois‐Grützmacher ◽  
...  
Author(s):  
D. A. Belinskaya ◽  
Yu. V. Chelusnova ◽  
V. V. Abzianidze ◽  
N. V. Goncharov

Poisoning with organophosphorus compounds occupy one of the leading places in exotoxicosis. At the first stage, the detoxification of organophosphates can be provided with the help of DNA or RNA aptamers that bind the poison in the bloodstream. Currently, the main method of searching for aptamers is the experimental method of systematic evolution of ligands by exponential enrichment (SELEX). In the process of aptamer selection, the target molecule must be immobilized via the streptavidin-biotin complex. Since the poison molecule is small in size, to increase its availability for binding to aptamer, it is necessary to use a spacer between organophosphorus compounds and biotin. The aim of this work was to optimize the selection of aptamers for organophosphorus compounds by increasing the availability of a poison molecule immobilized via the streptavidin-biotin complex on the example of paraoxon. For this purpose, three spacers between organophosphorus compounds and biotin were tested using molecular modeling methods: three links of polyethylene glycol (3-PEG), four links of polyethylene glycol (4-PEG) and aminohexyl. The conformation of the biotinylated paraoxon complex with streptavidin and the interaction of paraoxon with the binding fragment of the aptamer were modeled using molecular docking and molecular dynamics methods. The ability of biotinylated paraoxon to bind to the aptamer has been evaluated by analyzing the surface area of the paraoxon available to the solvent, as well as by calculating the free binding energies. It has been shown that only in the case of aminohexyl immobilized paraoxon can contact the aptamer. At the final stage, the synthesis of paraoxon bound to biotin via aminohexyl was carried out.


Author(s):  
V. A. Gorichny ◽  
D. Yu. Serdukov ◽  
A. V. Yazenok ◽  
A. V. Nosov ◽  
G. G. Zagorodnikov ◽  
...  

An outpatient examination of 530 employees engaged in work with chemical weapons related to organophosphorus compounds at chemically hazardous facilities was carried out. Risk factors for the development of cardiovascular diseases of atherogenic etiology among personnel of the facilities were studied in relation to the type of work performed using statistical analysis methods. When assessing the lipidogram, a high incidence of atherogenic dyslipidemia in a group of personnel involved in the storage of chemical weapons was found out in comparison with a group of people engaged in the destruction and control of chemical weapons (73.1 vs 61.2 vs 59.6%, p


Author(s):  
José Daniel Figueroa-Villar ◽  
Elaine C. Petronilho ◽  
Kamil Kuca ◽  
Tanos C. C. Franca

Background: Neurotoxic chemical warfare agents can be classified as some of the most dangerous chemicals for humanity. The most effective of those agents are the organophosphates (OPs) capable of restricting the enzyme acetylcholinesterase (AChE), which in turn controls the nerve impulse transmission. When AChE is inhibited by OPs, its reactivation can be usually performed through cationic oximes. However, until today it has not been developed one universal defense agent, with complete effective reactivation activity for AChE inhibited by any of the many types of existing neurotoxic OPs. For this reason, before treating people intoxicated by an OP, it is necessary to determine the neurotoxic compound that was used for contamination, in order to select the most effective oxime. Unfortunately, this task usually requires a relative long time, raising the possibility of death. Cationic oximes also display a limited capacity of permeating the blood-brain barrier (BBB). This fact compromises their capacity of reactivating AChE inside the nervous system. Methods: We performed a comprehensive search on the data about OPs available on the scientific literature today in order to cover all the main drawbacks still faced in the research for the development of effective antidotes against those compounds. Results: Therefore, this review about neurotoxic OPs and the reactivation of AChE, provides insights for the new agents’ development. The most expected defense agent is a molecule without toxicity and effective to reactivate AChE inhibited by all neurotoxic OPs. Conclusion: To develop these new agents it is necessary the application of diverse scientific areas of research, especially theoretical procedures as computational science (computer simulation, docking and dynamics); organic synthesis; spectroscopic methodologies; biology, biochemical and biophysical information; medicinal chemistry, pharmacology and toxicology.


2019 ◽  
Vol 23 (16) ◽  
pp. 1756-1770
Author(s):  
Sofia Strekalova ◽  
Mikhail Khrizanforov ◽  
Oleg Sinyashin ◽  
Yulia Budnikova

The interest in organophosphorus compounds with a C-P bond is due to their wide use in various fields, especially in medicine and agrochemistry. Prominent examples of anti-cancer, antibacterial, and anti-HIV agents are therapeutic candidates containing a phosphonic acid group fragment. This review provides modern synthetic methods for obtaining phosphorylated aromatic and heteroaromatic compounds with the participation of complexes and salts of various metals developed in recent years as well modern protocol - electrochemical synthesis which allows carrying out reactions at room temperature and normal pressure with no additional oxidants or bases. Herein, we demonstrate new trends and evolution of phosphorylation reactions in catalysis.


Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 714
Author(s):  
Gaber A. M. Mersal ◽  
Hamdy S. El-Sheshtawy ◽  
Mohammed A. Amin ◽  
Nasser Y. Mostafa ◽  
Amine Mezni ◽  
...  

The agricultural use of organophosphorus pesticides is a widespread practice with significant advantages in crop health and product yield. An undesirable consequence is the contamination of soil and groundwater by these neurotoxins resulting from over application and run-off. Here, we design and synthesize the mononuclear zinc(II) complexes, namely, [Zn(AMB)2Cl](ClO4) 1 and [Zn(AMB)2(OH)](ClO4) 2 (AMB = 2-aminomethylbenzimidazole), as artificial catalysts inspired by phosphotriesterase (PTE) for the hydrolysis of organophosphorus compounds (OPs) and simultaneously detect the organophosphate pesticides such as fenitrothion and parathion. Spectral and DFT (B3LYP/Lanl2DZ) calculations revealed that complexes 1 and 2 have a square-pyramidal environment around zinc(II) centers with coordination chromophores of ZnN4Cl and ZnN4O, respectively. Both 1 and 2 were used as a modifier in the construction of a biomimetic sensor for the determination of toxic OPs, fenitrothion and parathion, in phosphate buffer by square wave voltammetry. The hydrolysis of OPs using 1 or 2 generates p-nitrophenol, which is subsequently oxidized at the surface of the modified carbon past electrode. The catalytic activity of 2 was higher than 1, which is attributed to the higher electronegativity of the former. The oxidation peak potentials of p-nitrophenol were obtained at +0.97 V (vs. Ag/AgCl) using cyclic voltammetry (CV) and +0.88 V (vs. Ag/AgCl) using square wave voltammetry. Several parameters were investigated to evaluate the performance of the biomimetic sensor obtained after the incorporation of zinc(II) complex 1 and 2 on a carbon paste electrode (CPE). The calibration curve showed a linear response ranging between 1.0 μM (0.29 ppm) and 5.5 μM (1.6 ppm) for fenitrothion and 1.0 μM (0.28 ppm) and 0.1 μM (0.028 ppm) for parathion with a limit of detection (LOD) of 0.08 μM (0.022 ppm) and 0.51 μM (0.149 ppm) for fenitrothion and parathion, respectively. The obtained results clearly demonstrated that the CPE modified by 1 and 2 has a remarkable electrocatalytic activity towards the hydrolysis of OPs under optimal conditions.


1990 ◽  
Vol 60 (3) ◽  
pp. 375-387 ◽  
Author(s):  
Carole K. Grätzel ◽  
Marie Jirousek ◽  
Michael Grätzel

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