The influence of the reaction conditions on the yield of N4,O5′-diacetyl-2′,3′-dideoxy-2′,3′-didehydrocytidine (3), by electrochemical synthesis from N4,O2′,O5′-triacetyl-3′-bromo-3′-deoxycytidine (2), has been studied in order to evaluate the potential of this reaction for synthesis on a larger scale. We have characterized the half-wave potentials of the precursor (2) and the product (3) by polarography under various conditions, and found that reduction in the base moiety can easily take place giving by-products. Furthermore, this reduction consumes protons leading to rapid solvolysis in protic solvents. We have demonstrated for the first time that (3) can be formed near quantitatively in both protic and aprotic solvents. The success of the synthesis of (3) as well as of other 2′,3′-dideoxy 2′,3′-didehydro nucleosides also depends to a large extent on how uniform the current density across the working electrode surface can be maintained during electrolysis.
通过电化学合成 N4,O5′-二乙酰基-2′,3′-二脱氧-2′,3′-二脱氢胞苷 (3),研究了反应条件对其产率的影响、O2′,O5′-三乙酰基-3′-溴-3′-脱氧胞苷(2)的电化学合成方法进行了研究,以评估该反应在更大规模合成方面的潜力。我们在各种条件下通过极谱法测定了前体(2)和产物(3)的半波电位,发现碱基很容易发生还原,从而产生副产物。此外,这种还原会消耗质子,导致在质子溶剂中迅速溶解。我们首次证明,(3) 可以在质子和非质子溶剂中近乎定量地生成。(3) 以及其他 2′,3′-二脱氧 2′,3′-二脱氢核苷的合成成功与否,在很大程度上还取决于电解过程中工作电极表面的电流密度是否均匀。