Indoleamine 2,3-dioxygenase 1 (IDO1) is a promising target for cancer immunotherapy because it is overexpressed in a variety of tumor cells. IDO1 also plays an important role in the process of immune escape by tumors. In this study, we identified a novel IDO1 inhibitor KPYC12532 (5a) bearing an eight-membered ring-fused indole scaffold by screening our compound library. To develop novel IDO1 inhibitors, we conducted a structure-activity relationship study of 5a and found some compounds displaying comparable activity. These results provide useful insight for the design of novel IDO1 inhibitors.

中文翻译：

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具有八元环稠合吲哚支架的新型吲哚胺2，3-二加氧酶抑制剂的鉴定及其构效关系

吲哚胺2，3-二加氧酶1（IDO1）是癌症免疫疗法的有希望的靶标，因为它在多种肿瘤细胞中过表达。IDO1在肿瘤的免疫逃逸过程中也起着重要作用。在这项研究中，我们通过筛选我们的化合物文库，鉴定了一种新型的IDO1抑制剂KPYC12532（5a ），该抑制剂带有八元环稠合的吲哚支架。为了开发新型IDO1抑制剂，我们进行了5a的构效关系研究，发现了一些具有可比活性的化合物。这些结果为新型IDO1抑制剂的设计提供了有用的见识。