The presence of a stereoisomeric center at the phosphorus atom in phosphorothioate-modified oligonucleotides (PS-ONs) has been recognized as an important feature since the early stages of their development. Therefore, several studies have been conducted on the chirality of PS-ONs. In this study, we evaluated the stereo-biased chemistry of PS-ON duplexes. Depending on their absolute configurations, PS-ON duplexes were found to have significantly different and stereospecific reactivities towards simple alkylating reagent.

中文翻译：

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双链结构中硫代磷酸酯修饰的寡核苷酸的Sp和Rp异构体的不同反应性。

自从硫代磷酸酯修饰的寡核苷酸（PS-ON）发展的早期以来，就已经认识到在磷原子上立体异构中心的存在是重要的特征。因此，已经对PS-ON的手性进行了一些研究。在这项研究中，我们评估了PS-ON双链体的立体偏化学。根据它们的绝对构型，发现PS-ON双链体对简单的烷基化试剂具有显着不同的立体定向反应性。