Asymmetric sulfoxidation catalyzed by a vanadium bromoperoxidase: Substrate requirements of the catalyst
作者:Malin A Andersson、Stig G Allenmark
DOI:10.1016/s0040-4020(98)00956-9
日期:1998.12
An investigation of the catalytic effect on vanadium bromoperoxidase (VBrPO, from Corallina officinalis) on the oxidation of a series of prochiral sulfides by hydrogen peroxide, revealed that substrates having a cis-positioned carboxyl group are oxidized rapidly, giving the sulfoxide in >95% e.e. The pH-rate profile shows a typical sharp sigmoidal curve, indicative of a deprotonation event at around
对钒溴过氧化物酶(Corbrina officinalis的VBrPO )对过氧化氢氧化一系列前手性硫化物的催化作用的研究表明,底物具有顺式位置的羧基迅速被氧化,亚砜的> 95%ee。pH速率曲线显示出典型的S型曲线,表明在pH 6.4左右发生了去质子事件。相应的非蛋白水解的甲酯没有被该酶催化。当在溴离子的存在下进行VBrPO催化的氧化时,会发生立体选择性的快速损失。这被解释为是由于竞争反应的介入,该竞争反应涉及溴化物的氧化和随后形成溴mos离子中间体。