竹红菌甲素光敏氧化反应机制

本文报道了在竹红菌甲素的光敏氧化反应中, 原初反应产生了^1O2、O2和H2O2,在一些还原性底物(5-羟基色氨酸、色氨酸、组氨酸、蛋氨酸和赖氨酸等)的存在下, 体系中形成的O2量大大增加。证明了体系中的^1O2是通过三重态的竹红菌甲素和基态氧进行能量传递形成的, O2是体系中的竹红菌甲素负离子自由基和基态氧进行单电子转移的结果, H2O2是体系中存在的竹红菌甲素二价负离子还原基态氧的产物。在一些底物存在下, 次级反应产生了.OH。我们也发现竹红菌甲素具有弱的抽氢能力而生成一些有机自由基, 这些有机自由基的形成促进了各种活泼态氧的相互转化, 因此我们认为竹红甲素的光敏氧化是各种活泼态氧和一些有机自由基综合反应的结果。

The mechanism of hypocrellin a sensitized photooxidation reaction

In the primary reaction of hypocrellin A sensitized photooxidn., 1O2, O2. and H2O2 were formed, and the yield of O2. increased with the addition of a reducing substrate (such as 5-hydroxytryptophan, tryptophan, histidine, methionine and lysine). 1O2, O2. and H2O2 were resp. formed through energy transfer between triplet hypocrellin A and grout state O and the reduction of ground state O by hypocrellin A anions. Some free radicals were produced because of the weak H abstraction power of hypocrellin A, which promotes the interconversion of different forms of activated O species. Therefore, it was considered that both activated O species and free radicals were involved in the hypocrellin A sensitized photooxidn.