Analogs of Eu3+ DOTAM-Gly-Phe-OH and Tm3+ DOTAM-Gly-Lys-OH:: Synthesis and magnetic properties of potential PARACEST MRI contrast agents
Analogs of Eu3+ DOTAM-Gly-Phe-OH and Tm3+ DOTAM-Gly-Lys-OH:: Synthesis and magnetic properties of potential PARACEST MRI contrast agents
复制标题
DOI：
10.1016/j.bmc.2008.04.038
复制
发表时间：
2008-06-01
影响因子：
3.5
通讯作者：
Hudson, Robert H. E.
中科院分区：
文献类型：
--
作者：
Suchy, Mojmir;Li, Alex X.;Hudson, Robert H. E.
螯合的镧系元素离子，特别是钆，已被广泛用作磁共振成像中的造影剂。最近描述了一种用于产生对比度的新范例，称为PARACEST，其需要配体框架中存在的水或其他可交换质子的缓慢交换。在以前的工作中，我们已经描述了一种合成方法，用于制备DOTAM的二肽缀合物，用作PARACEST试剂。两个化合物具有有趣的磁性：DOTAM-Gly-Phe-OH的Eu（3+）配合物和DOTAM-Gly-Lys-OH的Tm（3+）配合物。为了了解这些配合物的结构与其磁性之间的关系，我们扩展了我们的合成方法，并制备了几种新的配合物。已经制备了这样的配体，其中末端苯丙氨酸部分已被色氨酸或酪氨酸取代，与具有α取代基的氨基酸残基的距离已改变，或者苯丙氨酸和赖氨酸已在肽序列中组合。这些配体的镧系元素（III）配合物的制备已经实现，并已确定其PARACEST性能。(C)2008爱思唯尔有限公司保留所有权利。
Chelated lanthanide ions, especially gadolinium, have found wide use as contrast agents in magnetic resonance imaging. A new paradigm for generating contrast, termed PARACEST, was recently described that requires the slow exchange of water or other exchangeable protons present in the ligand framework. In previous work, we have described a synthetic method for the preparation of dipeptide conjugates of DOTAM for use as PARACEST agents. Two compounds possessed interesting magnetic properties: the Eu(3+) complex of DOTAM-Gly-Phe-OH and the Tm(3+) complex of DOTAM-Gly-Lys-OH. To understand the relationship between the structure of these complexes and their magnetic properties, we have expanded our synthetic methodology and prepared several new complexes. Ligands have been prepared in which the terminal phenylalanine moieties have been replaced with tryptophan or tyrosine, the distance to the amino acid residue possessing an alpha-substituent has been changed, or phenylalanine and lysine have been combined in the peptide sequence. The preparation of lanthanide(III) complexes of these ligands has been achieved and their PARACEST properties have been determined. (C) 2008 Elsevier Ltd. All rights reserved.