94-63-3

Basic information

• Product Name: PYRIDINE-2-CARBOXALDOXIME METHIODIDE
• Synonyms: n-methylpyridinium-2-carboxaldoxime iodide;pyraloxime methoiodide;PRALIDOXIMELODIDE;2-PAM iodide, 2-PAM, Pralidoxime iodide;2-(Hydroximinomethyl)-1-methylpyridinium iodide;2-Pyridinaldoxim methojodid [german];2-PyridinealdoxiMe Methiodide 99%;Pralidoxime Iodid
• CAS NO: 94-63-3
• Molecular Formula: C₇H₉N₂O*I
• Molecular Weight: 264.06
• EINECS: 202-349-6
• Mol File: 94-63-3.mol
• Article Data: 8

Chemical Properties

• Melting Point: 220 °C (dec.)(lit.)
• Appearance: /
• Density: 1.7439 (estimate)
• Storage Temp.: 2-8°C
• Sensitive: Light Sensitive
• Merck: 13,7788
• CAS DataBase Reference: PYRIDINE-2-CARBOXALDOXIME METHIODIDE(CAS DataBase Reference)
• NIST Chemistry Reference: PYRIDINE-2-CARBOXALDOXIME METHIODIDE(94-63-3)
• EPA Substance Registry System: PYRIDINE-2-CARBOXALDOXIME METHIODIDE(94-63-3)

Safety Data

• Hazard Codes: Xn
• Statements: 22
• Safety Statements: 36-24
• WGK Germany: 3
• RTECS: UU4375000
• Hazardous Substances Data: 94-63-3(Hazardous Substances Data)

Usage

Definition

ChEBI: An organic iodide salt that has pralidoxime as the cation.

Safety Profile

Poison by subcutaneous, intravenous, intramuscular, and intraperitoneal routes. Moderately toxic by ingestion. Used as an antidote to the cholinesterase inhibitors of the parathion group. When heated to decomposition it emits highly toxic fumes of NO, and I-.

InChI:InChI=1/C7H8N2O.HI/c1-9-5-3-2-4-7(9)6-8-10;/h2-6H,1H3;1H

Upstream product

• 873-69-8 2-pyridinealdoxime 
• 74-88-4 methyl iodide 
• 3784-97-2 N-methyl pyridinium 2-carboxaldehyde iodide salt 
• 1121-60-4 pyridine-2-carbaldehyde 
• 1193-96-0 (E)-pyridin-2-aldoxime 

Downstream Products

• 3785-03-3 ortho-N-Methylcyanopyridinium iodide 
• 112272-69-2 C₉H₁₁N₂O₂⁽¹⁺⁾*I^(1-) 
• 14609-74-6 p-nitrophenolate 

Relevant articles and documents

Radiosynthesis, ex Vivo Biodistribution, and in Vivo Positron Emission Tomography Imaging Evaluations of [11C]2-Pyridinealdoxime Methiodide ([11C]2-PAM): A First-In-Class Antidote Tracer for Organophosphate Intoxication

2-Pyridinealdoxime methiodide (2-PAM) is a widely used antidote for the treatment of organophosphorus (OP) exposure that reactivates the target protein acetylcholinesterase. Carbon-11 2-PAM was prepared to more fully understand the in vivo mode of action, distribution, and dynamic qualities of this important countermeasure. Alkylation of 2-pyridinealdoxime with [11C]CH3I provided the first-in-class [11C]2-PAM tracer in 3.5% decay corrected radiochemical yield from [11C]CH3I, >99% radiochemical purity, and 4831 Ci/mmol molar activity. [11C]2-PAM tracer distribution was evaluated by ex vivo biodistribution and in vivo dynamic positron emission tomography (PET) imaging in na?ve (OP exposure deficient) rats. Tracer alone and tracer coinjected with a body mass-scaled human therapeutic dose of 30 mg/kg nonradioactive 2-PAM demonstrated statistically similar tissue and blood distribution profiles with the greatest uptake in kidney and significantly lower levels in liver, heart, and lung with lesser amounts in blood and brain. The imaging and biodistribution data show that radioactivity uptake in brain and peripheral organs is rapid and characterized by differential tissue radioactivity washout profiles. Analysis of arterial blood samples taken 5 min after injection showed ～82% parent [11C]2-PAM tracer. The imaging and biodistribution data are now established, enabling future comparisons to outcomes acquired in OP intoxicated rodent models.

Design, synthesis, and evaluation of guanylhydrazones as potential inhibitors or reactivators of acetylcholinesterase

Analogs of pralidoxime, which is a commercial antidote for intoxication from neurotoxic organophosphorus compounds, were designed, synthesized, characterized, and tested as potential inhibitors or reactivators of acetylcholinesterase (AChE) using the Ellman’s test, nuclear magnetic resonance, and molecular modeling. These analogs include 1-methylpyridine-2-carboxaldehyde hydrazone, 1-methylpyridine-2-carboxaldehyde guanylhydrazone, and six other guanylhydrazones obtained from different benzaldehydes. The results indicate that all compounds are weak AChE reactivators but relatively good AChE inhibitors. The most effective AChE inhibitor discovered was the guanylhydrazone derived from 2,4-dinitrobenzaldehyde and was compared with tacrine, displaying similar activity to this reference material. These results indicate that guanylhydrazones as well as future similar derivatives may function as drugs for the treatment of Alzheimer's disease.

Hydrolysis of carboxylate and phosphate esters using monopyridinium oximes in cationic micellar media

The reactions of p-nitrophenyl acetate (PNPA) with a series of monopyridinium oximes, viz. 2-PAM (2-hydroxyiminomethyl-1-methylpyridinium iodide), 3-PAM (3-hydroxyiminomethyl-1-methylpyridinium iodide), and 4-PAM (4-hydroxyiminomethyl-1-methylpyridinium iodide) have been studied in the presence of cationic surfactants of same hydrophobic chain length (C 16) within the concentration range of 0.5-6.0 mM at pH 8.0 under the pseudo-first-order condition. The observed rate constant (kobs) increases with increasing surfactant concentration culminating into a maximum, and this has been analyzed in detail following the concepts of micellar catalysis. The structure-activity relationship of the investigated oximes has been discussed, and 2-PAM was found to be the most reactive among all the three investigated oximes for the cleavage of PNPA. Esterolytic decomposition of p-nitrophenyldiphenyl phosphate with oximate ions (-CH=NO-) was followed in cetyltrimethylammonium bromide micelles at pH 9.0, and 4-PAM was the most reactive oxime for the micellar hydrolysis of phosphate ester. The apparent acid dissociation constants (pKa) of the investigated oximes have been determined spectrophotometrically.