Turner M J, Rosen G M
J Med Chem. 1986 Dec;29(12):2439-44. doi: 10.1021/jm00162a004.
The synthesis of three nitrones, 5-butyl-5-methyl-1-pyrroline 1-oxide (BMPO), 5,5-dipropyl-1-pyrroline 1-oxide (DPPO), and 2-aza-2-cyclopentenespirocyclopentane 2-oxide (CPPO), was conducted with use of the zinc/ammonium chloride reduction of appropriately substituted gamma-nitrocarbonyl compounds. The lipophilicity of these nitrones was estimated by determining their partition coefficients in a 1-octanol/water system. These nitrones were found to possess more lipophilic character than the most frequently used cyclic nitrone, 5,5-dimethyl-1-pyrroline 1-oxide (DMPO), which exhibits a partition coefficient of only 0.02. Hyperfine coupling constants for the spin trapping of superoxide and hydroxyl radical by the various nitrones were determined. The rate of spin trapping of superoxide with each nitrone was conducted by competitive kinetics with superoxide dismutase (SOD). In addition, the ability of DPPO and BMPO to spin trap free radicals generated during the metabolism of menadione by rat enterocyte cells was investigated. From these studies, DPPO and BMPO appear to be more suitable spin traps than DMPO when one is interested in monitoring free radicals generated intracellularly.
通过锌/氯化铵还原适当取代的γ-硝基羰基化合物，合成了三种硝酮，即5-丁基-5-甲基-1-吡咯啉1-氧化物（BMPO）、5,5-二丙基-1-吡咯啉1-氧化物（DPPO）和2-氮杂-2-环戊烯螺环戊烷2-氧化物（CPPO）。通过测定这些硝酮在1-辛醇/水体系中的分配系数来估计其亲脂性。发现这些硝酮比最常用的环状硝酮5,5-二甲基-1-吡咯啉1-氧化物（DMPO）具有更强的亲脂性，后者的分配系数仅为0.02。测定了各种硝酮对超氧阴离子和羟基自由基自旋捕获的超精细偶合常数。通过与超氧化物歧化酶（SOD）的竞争动力学研究了每种硝酮捕获超氧阴离子的自旋捕获速率。此外，还研究了DPPO和BMPO捕获大鼠肠细胞中甲萘醌代谢过程中产生的自由基的能力。从这些研究来看，当人们想要监测细胞内产生的自由基时，DPPO和BMPO似乎比DMPO更适合作为自旋捕获剂。
