Nucleophilic Aromatic Substitutions of 2-Halo-5-(sulfamoyl)benzoic Acids and <i>N</i>,<i>O</i>-Bis-alkylation via Phase Transfer Catalysis: Synthesis of RoRγ Inverse Agonist GSK2981278A
作者:Gregg A. Barcan、Jose J. Conde、Mohamed K. Mokhallalati、Mark G. Nilson、Shiping Xie、C. Liana Allen、Yemane W. Andemichael、Nicholas A. Calandra、David C. Leitch、Ling Li、Michael J. Morris
DOI:10.1021/acs.oprd.9b00147
日期:2019.7.19
original synthesis starting from methyl salicylate. A primary version of the route has been scaled up to deliver 125 kg of 1. However, the heating of a strong base in DMSO for an extended period during the bis-alkylation was found to be a safety concern for manufacturing. A safer and greener process was then developed utilizing a facile N,O-bis-alkylation, which was conducted under phase transfer conditions
GSK2981278A(1)是一种RORγ反向激动剂,可用作牛皮癣的潜在局部非类固醇疗法。基于(四氢-2 H-吡喃-4-基)甲醇与由2-卤代苯甲酸制备的芳基卤化物中间体的S N Ar反应,开发了1的新合成方法。该二价阴离子进行原位N,O-双-异丁基化,然后还原得到1。新路线消除了(四氢-2 H-吡喃-4-基)甲醇的对甲苯磺酸的遗传毒性,并从水杨酸甲酯开始的原始合成中进行了困难的还原胺化。该路线的主要版本已扩大规模,可提供125公斤的1。但是,发现在双烷基化过程中在DMSO中长时间加热强碱是制造过程中的安全隐患。然后,利用容易的N,O-双-烷基化开发了一种更安全,更环保的方法,该方法在相转移条件下,使用温和的碱(例如碳酸钾),并在绿色溶剂(例如水)中进行。从2-卤代苯甲酸到GSK2981278A(1)的简洁的四个阶段序列的总产率为41%。