We propose a synthetic process for the preparation of a benzoxazole building block for a programmed death-ligand 1 inhibitor that is a candidate currently under clinical investigation for cancer treatment. Our research focused on searching for mild, scalable, and ecofriendly conditions for the synthesis of benzoxazoles. To reduce the use of toxic reagents or solvents and to minimize the production of organic wastes, the cyclization reaction was performed in an aqueous micellar medium. This in-water benzoxazole synthesis gave comparable yields to previously reported processes, and was applied to a broad range of benzoxazoles with various substitution patterns, showcasing its effectiveness in ecofriendly benzoxazole cyclization reactions.

我们提出了一种用于制备程序性死亡配体 1 抑制剂的苯并恶唑结构单元的合成方法，该抑制剂是目前正在进行癌症治疗临床研究的候选药物。我们的研究重点是寻找温和、可扩展且生态友好的苯并恶唑合成条件。为了减少有毒试剂或溶剂的使用并尽量减少有机废物的产生，环化反应在水性胶束介质中进行。这种水中苯并恶唑合成的产率与之前报道的工艺相当，并且适用于具有各种取代模式的各种苯并恶唑，展示了其在环保苯并恶唑环化反应中的有效性。