Electron-deficient isoalloxazines: model systems for disulfide prodrug formation.
Electron-deficient isoalloxazines: model systems for disulfide prodrug formation.
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缺电子异咯嗪：二硫化物前药形成的模型系统。
DOI：
10.1021/jm00111a019
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发表时间：
1991
影响因子：
7.3
通讯作者：
Liu,Y
中科院分区：
文献类型：
--
作者：
Cashman,JR;Liu,Y
Drugs which contain a thiol functionality may be enzymatically or nonenzymatically oxidized to reactive metabolites, some of which cause adverse reactions. The synthesis of disulfide prodrugs to obviate unwanted drug side effects requires the development of novel catalysts. Herein, we describe the synthesis, structure-activity relationship, and mechanism investigations of the oxidationof model thiophenols with isoalloxazine disulfide formation catalysts. m-Nitrothiophenol (31) reacts with the electron-deficient 8-cyano-jV-3-(mercaptoalkyl)-10-phenylisoalloxazines (5-8) and non-electron-deficient JV-3-(mercaptoalkyl)-10-methylisoalloxazines (1-4) to produce m-nitrothiophenol disulfide. m-Nitrothiophenol (31) reacts with electron-deficient 8-cyano-10-phenyl-3-isoalloxazinepentanoic acid (10) or 10-methyl-3-isoalloxazinepentanoic acid (9) to form m-nitrothiophenol disulfide at a reduced rate, or not at all, respectively. Of the substituted isoalloxazines studied, electron-deficient isoalloxazines containing an N-3-mercaptoalkyl side chain were most efficient at catalyzing m-nitrothiophenol disulfide formation. Non-electron-deficient isoalloxazines without an N-3-alkyl mercaptan side chain (9) did not catalyze m-nitrothiophenol oxidation. Electron-deficient isoalloxazines without N-3-alkyl mercaptan side chains catalyzed m-nitrothiophenol oxidation at*/» the rate for isoalloxazine 5. From kinetic and product studies, the differences in catalytic activity of 1-10 were judged to be due to changes in thechemical properties of the isoalloxazines andthe ability to stabilize intramolecular thiol attack on the C (4a)-N (5) bond of the isoalloxazine. Electron-deficient isoalloxazines may be useful catalysts for the syntheses of disulfide prodrugs.
