Hurst P R
Int J Radiat Biol Relat Stud Phys Chem Med. 1975 Nov;28(5):447-52. doi: 10.1080/09553007514551271.
Radicals produced by X-irradiation at 77 K and at 300 K of cytosine. HCl crystals have been analysed by electron spin resonance spectroscopy. Four radicals have been identified: the anion radical of the cytosine molecule, the radical resulting from H-addition at position C6, the radical resulting from H-addition at position O2, and finally a radical resulting from addition of a Cl- to nitrogen N3. Hückel molecular orbital calculations are presented, which support the hypothesis according to which in unsaturated pyrimidines the site of hydrogenation or protonation depends on the state of the molecule.
通过电子自旋共振光谱对77K和300K下的胞嘧啶盐酸盐晶体经X射线辐照产生的自由基进行了分析。已鉴定出四种自由基：胞嘧啶分子的阴离子自由基、在C6位发生氢加成产生的自由基、在O2位发生氢加成产生的自由基，以及最后在氮N3位加成一个Cl-产生的自由基。给出了休克尔分子轨道计算结果，其支持了不饱和嘧啶中氢化或质子化位点取决于分子状态这一假设。
