2-[(hydroxyimino)methyl]-1-methylpyridinium

Description

Before aging occurs, patients can be treated with pralidoxime, which breaks the phosphorus–enzyme complex and regenerates the enzyme. Pralidoxime is a strong nucleophile. It reactivates phosphorylated enzymes in a two-staged reaction. First, a complex is formed between the oximate ion and the phosphorylated enzyme. Second, enzyme activity is restored and phosphorylated oxime is formed. The high reactivating ability of pralidoxime is attributed to its ability to combine with a negatively charged group on the surface of an enzyme and a high level of molecular correlation between oxime and phosphorylated cholinesterase. It is possible that oximes may react directly with the inhibitor, turning it into a harmless compound as well as reactivating the inhibitory enzyme both in blood and in tissue.

Uses

Pralidoxime is used for treating organophosphate poisonings, paralysis of skeletal muscle, and in general for cholinesterase crisis.

Definition

ChEBI: A pyridinium ion that is 1-methylpyridinium substituted by a (hydroxyimino)methyl group at position 2.

Synthesis

Pralidoxime, 2-pyridinaldoxime methylchloride (13.2.25), is synthesized by reacting piridine-2-aldehyde with hydroxylamine, giving piridine-2-aldoxime (13.2.24), which is further reacted with methyliodide, giving the desired pralidoxime (13.2.25) [52¨C55].

Veterinary Drugs and Treatments

Pralidoxime is used in the treatment of organophosphate poisoning, often in conjunction with atropine and supportive therapy.