From organophosphorous compounds

Phosphonium salts can be synthesized from unsaturated compounds by addition of a triarylphosphine and an acid in the presence of a palladium or rhodium catalyst. Transition metal catalysis turned out to be effective for the synthesis of organophosphorous compounds. 

Metrifonate is an organophosphorous compound that is effective only in the treatment of S. haematobium The active metabolite, dichlorvos, inactivates acetylcholinesterase and potentiates inhibitory cholinergic effects. The schistosomes are swept away from the bladder to the lungs and are trapped. Therapeutic doses produce no untoward side effects except for mild cholinergic symptoms. It is contraindicated in pregnancy, previous insecticide exposure, or with depolarizing neuromuscular blockers. Metrifonate is not available in the United States. 

Acetylcholine is removed from the synapse through hydrolysis into acetylCoA and choline by the enzyme acetylcholinesterase (AChE). Removing ACh from the synapse can be blocked irreversibly by organophosphorous compounds and in a reversible fashion by drugs such as physostigmine. 

Neurotransmitters are removed by translocation into vesicles or destroyed in enzyme-catalysed reactions. Acetylcholine must be removed from the synaptic cleft to permit repolarization and relaxation. A high affinity acetylcholinesterase (AChE) (the true or specific AChE) catalyses the hydrolysis of acetylcholine to acetate and choline. A plasma AChE (pseudo-AChE or non-specific AChE) also hydrolyses acetylcholine. A variety of plant-derived substances inhibit AChE and there is considerable interest in AChE inhibitors as potential therapies for cognition enhancement and for Alzheimer s disease. Organophosphorous compounds alkylate an active site serine on AChE and the AChE inhibition by this mechanism is the basis for the use of such compounds as insecticides (and unfortunately also as chemical warfare agents). Other synthetics with insecticidal and medical applications carbamoylate and thus inactivate AChE (Table 6.4). 

Introducing a variable evolution time x, a series of experiments with gated Li decoupling leads to /-resolved spectra where the C, Li multiplets appear parallel to the F axis [13]. A similar experiment has been applied to P, Li spin systems to separate the P, Li coupling constants from the homonuclear P, P interactions in lithiated organophosphorous compounds [108]. 

Especially it is necessary to emphasize that the mentioned elaboration was performed at one go what from the point of view of inhalation toxicology was impossible. If additionally to note that the exposure was characterized by atypical clinical intoxication picture in a comparison with sarin, and gas alarms with sensitivity at the level of maximum allowable concentration for organophosphorous compounds indicated nothing at lethal concentrations, it becomes clear why leading experts in the world could not come to know the particulars of these acts of chemical terrorism. 

Our previous investigation showed that oxime reactivators of ChE have direct influence on presynaptic and postsynaptic membranes after intoxication with OPC [7, 11]. In the ultrastructural investigation ofthe neuromuscular synapses after acute DDVP and Vx intoxications, the changes observed were similar to those resulting from neurotomy, which is the reason why we called this effect of organophosphorous compounds chemiconeurothomy [9], After i.m. application of reactivator of ChE TMB-4, the neuromuscular synapses recover their normal ultrastructure up to 10 days after intoxication. Without treatment, full recovery of ultrastructure will be after 30 days [9],... 

Fig. 8.2. Organophosphorous compounds. Malathion and parathion are organophosphorous insecticides. Nausea, coma, convulsions, respiratory failure, and death have resulted from the use of parathion by farmers who have gotten it on their skin. Malathion is similar in structure to parathion, but not nearly as toxic. The nerve gas Sarin, another organophospho-rus compound, was used in a terrorist attack in a Japanese subway.

Neutral extractants may be used for uncharged metal complexes, ionic salts, and strong acids. Examples include ethers such as diethylether and diisopropylether ketones such as methylisobutyl ketone (MIBK or hexone) and neutral organophosphorous compounds such as tri-n-butylphosphate (TBP), tri-n-octylphosphine oxide (TOPO), triphenylphosphate (TPP), and triphenyphosphine oxide (TPPO). Such neutral extractants have long been used for extracting actinides and lanthanides from nitric acid solutions. 

With regard to the foct that a great number of compounds of the CW Convention related arose from Organophosphorous basis, the application of TEA CO2 DIAL is shown as very perspective. Analysis of TEA CO2 DIAL usability and evaluation of test results for detection GB and further conq)ounds will be presented in the next part of this paper. 

In addition to the most conunon contaminants previously mentioned, pollutants such as hydrogen chloride, chlorine, hydrogen fluoride, and hydrogen bromide are produced as combustion products from the burning of chemical waste. When organophosphorous compounds are incinerated, corrosive phosphorous compounds are produced. Chlorides are also a product of municipal waste incinerators. 

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