作者:Luigi Fabbrizzi、Maurizio Licchelli、Angelo Perotti、Antonio Poggi、Giuliano Rabaioli、Donatella Sacchi、Angelo Taglietti
DOI:10.1039/b105480p
日期:2001.11.1
The tetra-amino tripodal ligand, 3, containing two anthracene subunits, has been prepared through a multi-step synthesis and its solution properties have been studied by potentiometric and spectrofluorimetric techniques. The zinc(II) complex, [ZnII(3)]2+, which displays the typical emission of anthracene derivatives, interacts with natural amino acids, showing a particular affinity towards phenylalanine and tryptophan. This selective behaviour of the complex derives from its ability to establish two kinds of interaction: (i) a metal–ligand interaction between the zinc(II) ion and the amino acid's carboxylate group; (ii) a π-stacking interaction involving the aromatic moieties positioned on the complex and on the amino acid, inducing an extra stability of the adducts with tryptophan and phenylalanine (7–8 kJ mol−1).
The formation of the 1 ∶ 1 adduct with tryptophan is signalled by a strong fluorescence quenching while no effect on the emission intensity has been observed in all other cases.
通过多步合成制备了含有两个蒽亚基的四氨基三足配体3,并通过电位测定和荧光分光光度技术研究了其溶液性质。锌(II)络合物[ZnII(3)]2+具有蒽衍生物的典型发射特性,与天然氨基酸相互作用,对苯丙氨酸和色氨酸表现出特殊的亲和力。复合物的这种选择性行为源于其建立两种相互作用的能力:(i)锌(II)离子和氨基酸的羧酸根之间的金属-配体相互作用; (ii) π 堆积相互作用涉及位于复合物和氨基酸上的芳香族部分,从而诱导色氨酸和苯丙氨酸 (7–8 kJ mol−1) 的加合物具有额外的稳定性。
与色氨酸形成 1:1 加合物的信号是强烈的荧光猝灭,而在所有其他情况下没有观察到对发射强度的影响。