Thermodynamic and structural study of complexation of phenylboronic acid with salicylhydroxamic acid and related ligands
作者:Mayte A. Martínez-Aguirre、Marcos Flores-Alamo、Anatoly K. Yatsimirsky
DOI:10.1002/aoc.4405
日期:2018.8
Stability constants of boronate complexes with a highly efficient bioconjugation ligand salicylhydroxamic acid, its derivatives and some structurally related compounds were determined by potentiometric and spectroscopic titrations at variable pH allowing one to obtain detailed stability – pH profiles and to identify the optimum pH for complexation with each ligand. The N,O‐binding of salicylhydroxamic
硼酸盐与高效生物共轭配体水杨基异羟肟酸的配合物,其衍生物和一些与结构相关的化合物的稳定性常数通过电位计和分光光度滴定法在不同的pH值下确定,从而获得详细的稳定性– pH曲线并确定与每种络合的最佳pH配体。水杨酸异羟肟酸通过硼酸与酚OH和异羟肟酸NH基团的缩合形成N,O-结合,是通过分离的苯基硼酸和4-硝基苯基硼酸配合物的晶体结构确定的。尽管对于N-甲基化水杨基异羟肟酸而言,这种结合是不可能的,但它仍会形成稳定的硼酸酯络合物,据称其涉及异常的7元–O–B–O–循环,并受11 H NMR研究。缺少邻-OH基团的异羟肟酸和水杨酰酰肼形成的硼酸酯络合物较不稳定,但其稳定性与消泡剂络合物相似,可用于共轭应用。与其他形成四面体阴离子络合物的配体相反,水杨酰胺肟形成四面体但在弱酸溶液中具有高稳定性的中性硼酸酯络合物。2,6-二羟基苯并异羟肟酸在中性和酸性溶液中的亲和力最高,超过了水杨基异羟肟酸(K obs