Oximes treatment

The Hoch-Campbell reaction of a-hydroxy ketoximes do not alter the course of the reaction although deprotonation probably took place concurrently for both the alcohol and the oxime. Treatment of oxime 40 afforded aziridine 42 in 30%, presumably via the intermediacy of azirine 41. a-Keto ketoximes would behave similarly to the a-hydroxy ketoximes in the Hoch-Campbell reaction after addition of the first equivalent of the Grignard reagent to the ketone. Therefore, the reaction between a-keto ketoxime 43 and phenylmagnesium bromide gave aziridine 45 in 41% yield, presumably via the intermediacy of azirine 44. 

The human intravenous bolus dose of oximes in nerve agent treatment ranges between 250 and 500 mg ". Side effects of oxime treatment in humans were monitored in 750 volunteers, and the main adverse effects reported were changes in blood pressure, pulse rate, dizziness, nausea and blurred vision . Oral administration of oximes produces gastrointestinal distress. ... 

Lifshitz, M., Rotenberg, M., Sofer, S., Tamiri, T., Almog, S. (1994). Carbamate poisoning and oxime treatment in children a clinical and laboratory study. Pediatrics 93 652-5. 

Standard post-exposure treatments include eoneurrent administration of anticholinergics, such as the musearinie cholinergic blocker atropine sulfate, and AChE reactivators, such as obidoxime and pyridine-2-aldoxime methochloride (also known as 2-PAM). Oximes cannot reactivate OP-inhibited AChE that has already aged . Therefore, traditional oxime treatment is considered to be less effective for those agents such as soman, for which aging is rapid (Worek et al, 2005). 

The duration of oxime treatment will depend on the presence of features, the clinical response and the erythrocyte AChE activity. It is recommended that the oxime should be administered for as long as atropine is indicated. For the majority of individuals this will be for less than 48 h the exception would be individuals exposed der-mally to VX where a depot of VX might result in prolonged intoxication. 

In doing so, the estimation of the effect of nerve-agent exposure and oxime treatment on AChE activity is hampered by the lack of human toxicokinetic data. Nevertheless, such model calculations may provide valuable information on the ability of different oximes to reactivate human AChE. 

Kaliste-Korhonen, E., Ryhanen, R., Ylitalo, R, and Hanninen, O., Cold exposure decreases the effectiveness of atropine-oxime treatment in organophosphate intoxication in rats and mice, Gen. Pharmac., 20, 805, 1989. 

Eshghi and Hassankhani (2007) studied the Beckmann rearrangement using sulfuric acid immobilized on the surface of silica gel (Scheme 5.57). Under these conditions, high conversion and excellent selectivity were found in the Beckmann rearrangement of cyclohexanone oxime. Treatment of carbamates and oxazolidi-nones with anhydrides in the presence of SSA under solvent-free conditions at room temperature results in the formation of V-acyl carbamates and oxazolidinones... 

Caprolactam, the monomer from which nylon 6 is synthesized, is prepared from cyclohexanone in two steps. In Step 1, cyclohexanone is treated with hydroxylamine to form cyclohexanone oxime. Treatment of the oxime with concentrated sulfuric acid in Step 2 gives caprolactam by a reaction called a Beckmann rearrangement. Propose a mechanism for the conversion of cyclohexanone oxime to caprolactam. 

The presentation and initial treatment of the characteristic acute cholinergic syndrome following severe OP exposure was considered in earlier chapters. Experience with OP pesticide poisoning has shown that in most cases, the signs and symptoms resolve after about 18 h with continuing anticholinergic and oxime treatment. Ventilation, if it had been required, can be discontinued at this stage. 

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