incorporated by unmodified standard procedures into four different self-complementary DNA and two RNA oligonucleotides. After photochemical removal of the protective group, elimination of formic aldehyde and spontaneous air oxidation, the nitroxide radicals were regenerated in high yield. The resulting spin-labeled palindromic duplexes could be directly investigated by PELDOR spectroscopy without further
                                    用2-硝基苄氧基甲基保护的
TEMPO自旋标记被连接到三个不同核苷的
氨基残基上:脱氧
胞苷,脱氧
腺苷和
腺苷。可以通过未修饰的标准程序将相应的亚
磷酰胺掺入四个不同的自互补DNA和两个RNA寡核苷酸中。在光
化学去除保护基,消除
甲醛和自发的空气氧化后,高产率地再生了
氮氧自由基。所得的自旋标记的回文双链体可以通过PELDOR光谱直接研究,而无需进一步的纯化步骤。通过PELDOR测量的自旋-自旋距离与从分子模型获得的值非常一致。