DAST and Deoxofluor are usually used for nucleophilic fluorination of nucleosides via S_N1 or S_N2 mechanism. DAST and Deoxo-fluor could enhance anomerization of N-substituted thymidine and 2'-deoxyuridine in dichloromethane into the more stable and favored α-anomers due to in-situ liberation of HF. This is strongly supported by computational calculations based on the density functional theory, that were performed to rationalize energy stability and electronic properties of both anomers in order to provide further insights into the proposed mechanism.

中文翻译：

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使用氟化剂对N-硝基嘧啶核苷进行异构化的协同合成和计算见解

DAST和脱氧氟通常通过S _N 1或S _N 2机制用于核苷的亲核氟化。DAST和Deoxo-fluor由于HF的原位释放，可增强二氯甲烷中N-取代的胸苷和2'-脱氧尿苷的异构化成更稳定和更有利的α-端基异构体。这是由基于密度泛函理论的计算计算强有力地支持的，该计算计算是为了合理化两种端基异构体的能量稳定性和电子性质，以便为提出的机理提供进一步的见解。