荧光黄素敏化胆固醇的单重态氧反应  

Singlet Oxygen Photooxidation of Cholesterol Sensitized by Lumiflavin

作　　者：江致勤[1] 曾代迅 刘有成[2] 

机构地区：[1]同济大学测试中心 [2]兰州大学应用有机化学实验室

出　　处：《化学学报》1989年第2期194-198,共5页Acta Chimica Sinica

摘　　要：黄素（Flavins）是一类典型的蛋白辅酶,其激发态参与许多重要的光生化过程。其中,黄素作为光敏剂可敏化一系列生物活性物质的光氧化,如氨基酸、蛋白质。DNA等,引起光致损伤作用。对于有重要生理作用的胆固醇（1）,已发现血卟啉、玫瑰红（RB）、9,10-二氰蒽（DCA）等光敏剂敏化其单线态氧（1O2）反应。The sensitized photooxidation of cholesterol (1) was carried out in several solvents, affording three products: cholest-6-en-3β, 5α-diol (2), cholest-5-en-3β, 7α-diol and -3β, 7β-clio1 (3) and cholest-5-en-3β-ol-7-one (4). It is found that the product distribution depends on sensitizer and solvent used. In partieular, a new product (4) is formed in the lumiflavin (LF)-sensitized photooxidation of 1. The rates of the photooxidations in polar solvents are considerably faster than that in nonpolar solvents which are favorable to the formation of 4 Based on the results, it is proposed that the photooxidation proceeds mainly via singlet oxygen (~1O_2) pathway and is followed by slow rearrangement of 2 to 3 and by hydrogen abstraction with triplet ~3LF, leading to the formation of enone 4.

关 键 词：荧光黄素 胆固醇 光氧化 

分 类 号：O644.14[理学—物理化学]