Mechanistic investigations on the efficient catalytic decomposition of peroxynitrite by ebselen analogues
作者:Krishna P. Bhabak、Amit A. Vernekar、Surendar R. Jakka、Gouriprasanna Roy、Govindasamy Mugesh
DOI:10.1039/c0ob01234c
日期:——
In this study, ebselen and its analogues are shown to be catalysts for the decomposition of peroxynitrite (PN). This study suggests that the PN-scavenging ability of selenenyl amides can be enhanced by a suitable substitution at the phenyl ring in ebselen. Detailed mechanistic studies on the reactivity of ebselen and its analogues towards PN reveal that these compounds react directly with PN to generate highly unstable selenoxides that undergo a rapid hydrolysis to produce the corresponding seleninic acids. The selenoxides interact with nitrite more effectively than the corresponding seleninic acids to produce nitrate with the regeneration of the selenenyl amides. Therefore, the amount of nitrate formed in the reactions mainly depends on the stability of the selenoxides. Interestingly, substitution of an oxazoline moiety on the phenyl ring stabilizes the selenoxide, and therefore, enhances the isomerization of PN to nitrate.
本研究表明,
依布硒及其类似物是分解过氧化
亚硝酸盐(
PN)的催化剂。这项研究表明,通过在
依布硒的苯基环上进行适当的取代,可以增强
硒基酰胺对过氧化
亚硝酸盐的清除能力。对
依布硒及其类似物与
PN 反应的详细机理研究表明,这些化合物直接与
PN 反应生成极不稳定的
硒氧化物,这些
硒氧化物经过快速
水解生成相应的
硒酸。与相应的
硒酸相比,
硒氧化物能更有效地与
亚硝酸盐相互作用,生成
硝酸盐,同时
硒基酰胺再生。因此,反应中形成的
硝酸盐量主要取决于
硒氧化物的稳定性。有趣的是,在苯基环上取代一个
噁唑啉分子可以稳定
硒氧化物,从而提高
PN 向
硝酸盐的异构化。