We present a novel chemical scaffold for cysteine‐reactive covalent inhibitors. Chloromethyl triazoles (CMTs) are readily accessed in only two chemical steps, thus enabling the rapid optimization of the pharmacological properties of these inhibitors. We demonstrate the tunability of the CMTs towards a specific biological target by synthesizing AA‐CW236 as the first potent non‐pseudosubstrate inhibitor of the O⁶‐alkylguanine DNA methyltransferase (MGMT), a protein of major clinical significance for the treatment of several severe cancer forms. Using quantitative proteomics profiling techniques, we show that AA‐CW236 exhibits a high degree of selectivity towards MGMT. Finally, we validate the effectiveness of our MGMT inhibitor in combination with the DNA alkylating drug temozolomide in breast and colon cancer cells by fluorescence imaging and a cell‐viability assay. Our results may open a new avenue towards the development of a clinically approved MGMT inhibitor.

中文翻译：

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化学蛋白质组学启用的DNA修复蛋白MGMT的有效和选择性抑制剂的发现。

我们提出了一种用于半胱氨酸反应性共价抑制剂的新型化学支架。氯甲基三唑（CMT）只需两个化学步骤即可轻松获得，因此可以快速优化这些抑制剂的药理特性。通过合成AA-CW236作为O ⁶的第一种有效非伪底物抑制剂，我们证明了CMT向特定生物靶标的可调性-烷基鸟嘌呤DNA甲基转移酶（MGMT），一种对几种严重癌症形式的治疗具有重要临床意义的蛋白质。使用定量蛋白质组学分析技术，我们表明AA-CW236对MGMT表现出高度的选择性。最后，我们通过荧光成像和细胞活力分析验证了我们的MGMT抑制剂与DNA烷基化药物替莫唑胺在乳腺癌和结肠癌细胞中的有效性。我们的结果可能为临床批准的MGMT抑制剂的开发开辟新途径。