A new and practical synthesis of GS-441524, the key intermediate for remdesivir, is developed. 4-Amino-7-iodopyrrolo[2,1-f][1,2,4]triazine is protected by DMF-DMA, and reacted with 2,3,5-tri-O-benzyl-D-ribonolactone to give the product in 61% isolated yield. The next cyanation and debenzylation are carried out at −30 °C successively in 67% yield over two steps with >99% purity (HPLC). Purification methods of the intermediates and the final product involved in the route are developed.

中文翻译：

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瑞德西韦的关键中间体 GS-441524 的新型实用合成

开发了一种新的实用合成 GS-441524，即瑞德西韦的关键中间体。4-氨基-7-碘吡咯并[ 2,1- f ][1,2,4]三嗪受DMF-DMA保护，并与2,3,5-三-O-苄基-D-核糖内酯反应得到产品的分离产率为 61%。接下来的氰化和脱苄基在 -30 °C 下连续进行，分两步以 67% 的产率进行，纯度 >99% (HPLC)。开发了该路线所涉及的中间体和最终产品的纯化方法。