期刊
CHEMISTRY-A EUROPEAN JOURNAL
卷 19, 期 27, 页码 9050-9058出版社
WILEY-V C H VERLAG GMBH
DOI: 10.1002/chem.201300539
关键词
arylboronic esters; H2O2 induction; quinone methides; substitutent effects; trapping
资金
- National Cancer Institute [1R15 A152914-01]
- Great Milwaukee Foundation
- University of Wisconsin-Milwaukee (UWM)
A series of arylboronic esters containing different aromatic substituents and various benzylic leaving groups (Br or N+Me3Br-) have been synthesized. The substituent effects on their reactivity with H2O2 and formation of quinone methide (QM) have been investigated. NMR spectroscopy and ethyl vinyl ether (EVE) trapping experiments were used to determine the reaction mechanism and QM formation, respectively. QMs were not generated during oxidative cleavage of the boronic esters but by subsequent transformation of the phenol products under physiological conditions. The oxidative deboronation is facilitated by electron-withdrawing substituents, such as aromatic F, NO2, or benzylic N+Me3Br-, whereas electron-donating substituents or a better leaving group favor QM generation. Compounds containing an aromatic CH3 or OMe group, or a good leaving group (Br), efficiently generate QMs under physiological conditions. Finally, a quantitative relationship between the structure and activity has been established for the arylboronic esters by using a Hammett plot. The reactivity of the arylboronic acids/esters and the inhibition or facilitation of QM formation can now be predictably adjusted. This adjustment is important as some applications may benefit and others may be limited by QM generation.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据