Efficient methods for the synthesis of three dipeptide mimetics with diazabicycloalkanone amino acid scaffolds were developed. Among them, compound 3, which contains a 1,5-diazabicyclo[6,3,0]dodecanone amino acid core structure, was used as the key intermediate of a clinical staged IAP inhibitor SM-406 (Xevinapant). Compared with the reported methods for the synthesis of compound 3 and its derivatives, our method is more efficient and more suitable for large scale preparation.

中文翻译：

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SM-406 (Xevinapant) 及其类似物关键中间体的合成

开发了用二氮杂双环烷酮氨基酸支架合成三种二肽模拟物的有效方法。其中，含有1,5-二氮杂双环[6,3,0]十二烷酮氨基酸核心结构的化合物3被用作临床分期IAP抑制剂SM-406（Xevinapant）的关键中间体。与已报道的化合物3及其衍生物的合成方法相比，我们的方法效率更高，更适合大规模制备。