Synthesis of 2‐chloro‐1,1‐dimethylethyl and 2‐chloro‐2,2‐dimethylethyl analogues of ifosfamide was performed via aziridine intermediate. In vitro metabolic activation showed that both compounds are metabolised at a rate similar to the parent drug. However, their anticancer activity against L1210 leukaemia in mice was lower as compared with ifosfamide. The reduction of antitumour efficiency of examined analogues is probably caused by a lower ability to cross‐link DNA by their final, active metabolites.

中文翻译：

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异环磷酰胺甲基类似物的合成、体外代谢研究和抗肿瘤活性

通过氮丙啶中间体合成异环磷酰胺的 2-氯-1,1-二甲基乙基和 2-氯-2,2-二甲基乙基类似物。体外代谢激活显示两种化合物的代谢速率与母体药物相似。然而，与异环磷酰胺相比，它们对小鼠 L1210 白血病的抗癌活性较低。检查的类似物抗肿瘤效率的降低可能是由于其最终的活性代谢物交联 DNA 的能力较低所致。