The development of a route applicable to the preparation of acyclic glutamic acid-based chelating ligands bearing two different auxiliary donor groups linked to the nitrogen atom by methylene spacers is described and applied to the synthesis of the new polydentate ligand HBGl₃, the first example of such a structure. The synthesis is accomplished using a strategy employing reductive amination and t-butyl ester protected intermediates. The most basic pK_a values for the HBGl₃ ligand have been estimated via potentiometric and UV–Visible titration techniques.

中文翻译：

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合成策略HBGl ₃，一种谷氨酸衍生的配体，在氮原子上带有酚和氮杂羧酸供体基团

描述了开发适用于制备带有两个不同辅助供体基团的无环谷氨酸基螯合配体的路线，该辅助供体基团通过亚甲基间隔基与氮原子连接，并将其应用于新的多齿配体HBGl ₃的合成。这样的结构。合成是通过采用还原胺化和叔丁酯保护的中间体的策略完成的。最基本的pK_一个为值HBGl ₃配体已经通过电位和紫外-可见滴定技术来估计。