Potentiation organophosphorus compounds

Indeed, these reactions proceed at 25 °C in ethanol-aqueous media in the absence of transition metal catalysts. The ease with which P-H bonds in primary phosphines can be converted to P-C bonds, as shown in Schemes 9 and 10, demonstrates the importance of primary phosphines in the design and development of novel organophosphorus compounds. In particular, functionalized hydroxymethyl phosphines have become ubiquitous in the development of water-soluble transition metal/organometallic compounds for potential applications in biphasic aqueous-organic catalysis and also in transition metal based pharmaceutical development [53-62]. Extensive investigations on the coordination chemistry of hydroxymethyl phosphines have demonstrated unique stereospe-cific and kinetic propensity of this class of water-soluble phosphines [53-62]. Representative examples outlined in Fig. 4, depict bidentate and multidentate coordination modes and the unique kinetic propensity to stabilize various oxidation states of metal centers, such as Re( V), Rh(III), Pt(II) and Au(I), in aqueous media [53 - 62]. Therefore, the importance of functionalized primary phosphines in the development of multidentate water-soluble phosphines cannot be overemphasized. 

All these observations underscore the potential for application of appropriate OPAs to the destruction of organophosphorus compounds with anticholinesterase activity (Cheng and Calomiris 1996). However, since, hydrolysis results in release of fluoride, the possibility of its subsequent incorporation into organic substrates to produce fluoroacetate and 4-fluorothreonine (Reid et al. 1995) may be worth consideration. 

Although analysis of urine samples for the presence of these metabolites represents a potential means of assessing recent human exposure to diazinon, these metabolites can originate from exposure to other organophosphorus compounds and, therefore, are not specific for diazinon exposure. Additionally, these studies do not report a quantitative association between metabolite levels and exposure to diazinon in humans. Thus, these biomarkers are only indicative of exposure to diazinon (or other organophosphorus compounds) and are not specifically useful for diazinon exposure nor for dosimetric analysis. Further studies designed to refine the identification of metabolites specific to diazinon and provide dosimetric data will be useful in the search for a more dependable biomarker of diazinon exposure. 

Alkyl-substituted monoamides are known as extractants for the uranyl cation and they could potentially be considered as alternatives to organophosphorus compounds in nuclear fuel reprocessing. In toluene, the uranyl cation forms complexes with two monoamide molecules. These relatively simple molecules were selected for computer-aided design,14 taking into account a lot of synthetic and experimental work that must be done to prove the modeling predictions. 

Varnek, A.A. Kuznetsov, A.N. Petrukhin, O.M. Electrostatic potential distribution and extraction ability of some organophosphorus compounds. Zh. Structumoi Khim. (Russ.) 1989, 30, 44-48. 

Richards, P.G., Johnson, M.K., Ray, D.E. (2000). Identification of acylpeptide hydrolase as a sensitive site for reaction with organophosphorus compounds and a potential target for cognitive enhancing drugs. Mol. Pharmacol. 58 577-83. 

Richardson, R.J. (1995). Assessment of the neurotoxic potential of chlorpyrifos relative to other organophosphorus compounds a critical review of the literature. J. Toxicol. Environ. Health 44 135-65. 

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