描述了对 duocarmycin SA 的缩短、简化和扩展类似物的检查,并构成了对连接的 DNA 结合亚基作用的详细研究。除了通过小沟非共价接触增强 DNA 结合亲和力和选择性外,这些研究与随附文章的研究一起表明,DNA 烷基化反应的催化需要扩展的刚性 N2 酰胺取代基。DNA 烷基化的这种激活与 pH 无关,我们认为它是由结合诱导的试剂构象变化引起的,这增加了它们的固有反应性。底物的基态不稳定是由连接酰胺中的扭曲引起的,该扭曲破坏了烷基化亚基的乙烯基酰胺稳定性并激活了亲核加成试剂。
Examination of the role of the duocarmycin SA methoxy substituents: Identification of the minimum, fully potent DNA binding subunit
作者:Dale L. Boger、Bernd Bollinger、Douglas S. Johnson
DOI:10.1016/0960-894x(96)00401-5
日期:1996.9
The preparation and examination of 4-7 revealed that (+)-5 and (+)-duocarmycin SA were indistinguishable. In contrast, 6 and 7 exhibited properties more analogous to 4 illustrating that the C6 and C7 methoxy substituents of duocarmycin SA contribute little or nothing to its properties. Thus, the C5 methoxy substituent of the 5,6,7-trimethoxyindole subunit of duocarmycin SA is necessary and sufficient for observation of the full potency of the natural product. Copyright (C) 1996 Elsevier Science Ltd