Stereoselective inhibition of human butyrylcholinesterase by pbosphonotbiolate analogs of (+)- and (−)-cocaine
作者:Clifford E. Berkman、Gail E. Underiner、John R. Cashman
DOI:10.1016/s0006-2952(97)00403-6
日期:1997.12
analogs for both (-)- and (+)-cocaine hydrolysis were synthesized and tested as inhibitors of human BuChE-catalyzed hydrolysis of butyrylthiocholine. The phosphonothiolate corresponding to the transition state for (-)-cocaine hydrolysis was a competitive inhibitor with a Ki value of 55.8 microM. The phosphonothiolate corresponding to the transition state for (+)-cocaine hydrolysis gave a Ki value of
先前已经显示,人丁酰胆碱酯酶(BuChE; EC 3.1.1.8)将可卡因(苯甲酰芽子碱甲酯)水解为芽子甲酯,是将这种物质解毒成无药理活性代谢物的重要手段。天然存在的(-)-可卡因水解成芽子碱甲酯的速度比非天然(+)-可卡因异构体慢约2000倍。与先前的研究很好地吻合,(-)可卡因以相对良好的亲和力与人BuChE结合,并竞争性地抑制了Ki值为8.0 microM的分光光度法底物丁酰硫代胆碱的水解。同样,(+)可卡因也显示出对人BuChE的相对高亲和力,竞争性抑制了丁酰硫代胆碱的水解,Ki值为5.4 microM。合成了对应于(-)-和(+)-可卡因水解的过渡态类似物的硫代膦酸酯,并作为人BuChE催化的丁硫代胆碱水解的抑制剂进行了测试。对应于(-)-可卡因水解的过渡态的硫代磷酸硫醚是竞争性抑制剂,Ki值为55.8 microM。对应于(+)-可卡因水解的过渡态的硫代膦酸酯给出的Ki值为25