Pyrimidinone: versatile Trojan horse in DNA photodamage?
Pyrimidinone: versatile Trojan horse in DNA photodamage?
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DOI：
10.1039/c5pp00114e
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发表时间：
2015-08
影响因子：
3.1
通讯作者：
M. Micheel;C. Ziegenbein;P. Gilch;G. Ryseck
中科院分区：
文献类型：
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作者：
M. Micheel;C. Ziegenbein;P. Gilch;G. Ryseck
(6-4)相邻嘧啶DNA碱基之间的光损伤容易发生二次光化学。已经表明，单重态激发（6-4）部分形成杜瓦价异构体以及三重态激发。我们在此报告 (6-4) 光损伤最小模型 1-甲基-2(1 H )-嘧啶酮的三重态。重点在于其从醇和碳水化合物中提取氢原子的能力。稳态和时间分辨实验始终产生 ∼10^4 M^−1 s^−1 的氢提取双分子速率常数。正如泽布林 (1-(β-d-呋喃核糖基)-2(1 H )-嘧啶酮) 实验所示，该过程也在分子内发生。
(6-4) Photolesions between adjacent pyrimidine DNA bases are prone to secondary photochemistry. It has been shown that singlet excited (6-4) moieties form Dewar valence isomers as well as triplet excitations. We here report on the triplet state of a minimal model for the (6-4) photolesion, 1-methyl-2(1 H )-pyrimidinone. Emphasis is laid on its ability to abstract hydrogen atoms from alcohols and carbohydrates. Steady-state and time-resolved experiments consistently yield bimolecular rate constants of ∼10^4 M^−1 s^−1 for the hydrogen abstraction. The process also occurs intramolecularly as experiments on zebularine (1-(β- d -ribofuranosyl)-2(1 H )-pyrimidinone) show.