The preparation of new derivatives of benzo[1, 2‐c]1, 2, 5‐oxadiazole N‐oxide is described. These derivatives were chosen in order to investigate and confirmprevious structural features found necessary to display an adequate antitrypanosomal activity. The compounds synthesized were tested in vitro against epimastigote forms of Trypanosoma cruzi.The presence of a bromine atom in the benzo system produced compounds less active than the corresponding de‐halo analogues. However, 5‐(bromomethyl)‐7‐bromobenzo[1, 2‐c]oxadiazole N‐oxide (23) was the most cytotoxic compound against T. cruzi. For this, the 50% inhibitory dose (ID50) was determined, it was of the same order as that of Nifurtimox. From statistical analysis we could establish a relationship between lipophilic‐hydrophilic balance of the derivatives with their effectiveness as antichagasic compounds.

中文翻译：

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Benzo[1, 2-c]1, 2, 5-oxadiazole N-Oxide 衍生物作为潜在的抗锥虫药。结构-活动关系。第二部分

描述了苯并 [1, 2-c]1, 2, 5-恶二唑 N-氧化物的新衍生物的制备。选择这些衍生物是为了研究和确认先前发现的表现出足够的抗锥虫活性所必需的结构特征。合成的化合物在体外针对克氏锥虫的上鞭毛体形式进行了测试。苯并系统中溴原子的存在产生的化合物活性低于相应的脱卤类似物。然而，5-(溴甲基)-7-溴苯并 [1, 2-c] 恶二唑 N-氧化物 (23) 是对 T. cruzi 最具细胞毒性的化合物。为此，确定了 50% 抑制剂量 (ID50)，它与 ​​Nifurtimox 的数量级相同。