A four chemical step route to 2′-deoxy-2′-fluoro-N⁶,3′-dipivaloylarabinoadenosine and 2′-deoxy-2′-fluoro-N⁶-pivaloylarabinoadenosine from adenosine was developed for the preparation of ulevostinag in our STING (Stimulator of Interferon Genes) program. This 4-step route is based on the selective protection of adenosine with a dynamic kinetic crystallization of the desired N⁶,3′,5′-tripivaloyladenosine. This is followed by activation of the 2′-alcohol as its triflate without pivalate migration. Subsequently, the triflate is displaced with fluoride under mild conditions. Selective deprotection of the esters can give a variety of mono- and diacylated products including the 3′- or 5′-protected 2′-fluoroarabinonucleoside in the presence of the N⁶-pivalamide.

中文翻译：

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通过动态动力学结晶选择性合成 N6,3′，5′-三乙酰腺苷和区域选择性制备 2′-脱氧-2′-氟阿拉伯腺苷


从腺苷中开发出 2'-脱氧-2'-氟-N^6,3'-dipivaloylarabinoadenosine 和 2'-脱氧-2'-fluoro-N 6-pivaloylarabinoadenosine 的四化学步骤路线，用于在我们的 STING（干扰素基因刺激剂）计划中制备 ulevostinag。该 4 步路线基于腺苷的选择性保护，具有所需 N^6,3′，5′-三硫酰腺苷的动态动力学结晶。随后激活 2′-醇作为其三氟甲磺酸，而没有戊酸酯迁移。随后，在温和的条件下用氟化物置换三氟甲磺酸。酯的选择性脱保护可以得到各种单酰化和二酰化产物，包括在 N⁶-戊酰胺存在下受 3′ 或 5′ 保护的 2′-氟阿拉伯二核苷。