Efficient radiotherapy requires the concomitant use of ionizing radiation (IR) and a radiosensitizer. In the present work uracil-5-yl O-sulfamate (SU) is tested against its radiosensitizing potential. The compound possesses appropriate dissociative electron attachment (DEA) characteristics calculated at the M06-2X/6-31++G(d,p) level. Crossed electron–molecular beam experiments in the gas phase demonstrate that SU undergoes efficient DEA processes, and the single C–O or S–O bond dissociations account for the majority of fragments induced by electron attachment. Most DEAs proceed already for electrons with kinetic energies of ∼0 eV, which is supported by the exothermic thresholds calculated at the M06-2X/aug-cc-pVTZ level. However, in water solution under reductive conditions and physiological pH, SU does not undergo radiolysis, which demonstrates the crucial influence of aqueous environment on the radiosensitizing properties of modified nucleosides.

中文翻译：

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尿嘧啶 5-基 O-氨基磺酸酯：一种幻觉放射增敏剂。模拟核碱基放射增敏衍生物的缺陷。

有效的放射治疗需要同时使用电离辐射 (IR) 和放射增敏剂。在目前的工作中 uracil-5-yl O- 氨基磺酸盐 (SU) 已针对其放射增敏潜力进行了测试。该化合物具有在 M06-2X/6-31++G(d,p) 水平计算的适当的解离电子附着 (DEA) 特性。气相中的交叉电子-分子束实验表明，SU 经历了有效的 DEA 过程，并且单个 C-O 或 S-O 键解离占电子附着诱导的大部分碎片。大多数 DEA 已经开始处理动能为 ∼0 eV 的电子，这得到了在 M06-2X/aug-cc-pVTZ 水平计算的放热阈值的支持。然而，在还原条件和生理 pH 值下的水溶液中，SU 不会发生辐射分解，这表明水性环境对修饰核苷的放射增敏特性具有至关重要的影响。