Mimicking Enzymes: Cooperation between Organic Functional Groups and Metal Ions in the Cleavage of Phosphate Diesters
作者:Monica Livieri、Fabrizio Mancin、Giacomo Saielli、Jik Chin、Umberto Tonellato
DOI:10.1002/chem.200600672
日期:2007.3.5
amino groups, were prepared and their Zn(II) complexes were studied as catalysts for the cleavage of bis-p-nitrophenyl phosphate (BNP) and 2-hydroxypropyl-p-nitrophenyl phosphate (HPNP) diesters. A comparative kinetic study indicated that the insertion of organic groups, capable of acting as nucleophiles or as hydrogen-bond donors, substantially increases the hydrolytic activity of the metal complex
制备了一系列衍生自双-2-吡啶基甲胺结构的,带有附加羟基或芳香氨基的配体,并研究了其Zn(II)配合物作为裂解双-对-硝基苯基磷酸酯(BNP)的催化剂和2-羟丙基-对硝基苯基磷酸酯(HPNP)二酯。一项比较动力学研究表明,能够充当亲核试剂或氢键供体的有机基团的插入大大提高了金属络合物的水解活性。解剖各组的影响后发现,反应性的提高可以达到三个数量级。所研究系统的效率提高,以及活性亲核试剂的低pK(a)值所带来的好处,导致在6的pH值下BNP裂解加速了六个数量级。pH依赖的反应性曲线呈钟形曲线,在pH 9时观察到最大反应性。通过动力学分析,NMR光谱实验和理论计算,详细研究了反应机理和配合物的结构。裂解HPNP的复合物的反应性与BNP观察到的反应性非常相似,但由于不同的反应机理,所获得的促进作用较低。和理论计算。裂解HPNP的复合物的反应性与BNP观察到的反应性非常相似,但由于不同的反应机理,