|
KMID : 0369819940240040273
|
|
Jorunal of Korean Pharmaceutical Sciences
1994 Volume.24 No. 4 p.273 ~ p.279
|
|
|
Stability of Mono - and Bis - pyridinium Oximes in Aqueous Systems
|
|
정창희/Jung CH
최승주/서원준/석대은/Choi SJ/Seo WJ/Sok DE
|
|
|
Abstract
|
|
|
|
The stability of three oximes, Hl-6 [(4-carbamoyl-2'[(hydroxyimino)-methyl]- 1,1'-oxydimethylenedi-(pyridinium chloride)], Hl-CN [(4 cyano-2'-[(hydroxyimino)-methyl] -1,1'-oxydimethylene-di-(pyridinium chloride)], and 2-PAM [pralidoxime chloride] in aqueous solutions was evaluated by HPLC assay. The rate of degradation is dependent on the pH as well as the temperature at which the solution is stored. The optimum pH for the stability of these oximes was pH 2 to 3. The degradation rate constant for 2-PAM (kat70?C, 2.07×10?4/hr;Eavalue, 27.2 kcal/mol) was smaller than those for bis-pyridiniumoximes, Hl-6 (kat70?C, 3.38×10?3/hr) and Hl-CN (kat70?C, 8.66×10?3/hr;Eavalue, 20.7 kcal/mol). In mechanistic analyses, it was found that Hl-CN was decomposed through not only the hydrolysis of nitrile group but also the cleavage of methylene ether bridge, in contrast to Hl-6 which was degraded mainly through the cleavage of methylene ether bridge.
|
|
|
KEYWORD
|
|
|
Oxime, Kinetics, Stability
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|