Exploiting the Fluxionality of Lanthanide Complexes in the Design of Paramagnetic Fluorine Probes.
Exploiting the Fluxionality of Lanthanide Complexes in the Design of Paramagnetic Fluorine Probes.
复制标题
顺磁性氟探针设计中镧系元素配合物的流动性的开发。
DOI：
10.1021/acs.inorgchem.1c03908
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发表时间：
2022-03-07
影响因子：
4.6
通讯作者：
Pierre VC
中科院分区：
文献类型：
--
作者：
Wilharm RK;Ramakrishnam Raju MV;Hoefler JC;Platas-Iglesias C;Pierre VC
氟-19核磁共振成像越来越被认为是一种生物分子成像的工具，但这种技术的灵敏度非常低，限制了大多数应用。以往的研究早已确定，提高19F分子探针的灵敏度需要增加每个探针的氟核数量，并减少其纵向弛豫时间。后者很容易通过将氟原子靠近顺磁性金属离子（如镧系元素（III））来实现。然而，增加每个分子中氟原子的数目，只有在所有氟原子核在化学上相等的情况下才有用。以前实现这种等效性的尝试集中在设计高度对称和刚性的氟化大环配体上。一种更简单的方法是利用具有开放配位的高通量镧系配合物，这些配合物对磷酸盐和膦化物质具有高亲和力。计算研究表明，lniii - trenn - mam具有高通量，在至少六个不同的异构体之间快速相互转化。在室温下的中性水中，lniii - trenn - mam可结合两种或三种等量的氟化磷酸盐。在三元配合物中，19F核靠近LnIII中心，使氟核的弛豫时间减少了40倍。有利的是，氟膦酸结合的镧系配合物也具有高通量，使得所有19F核在化学上是等效的，并且显示具有小LIS的单个19F信号。动态平均的氟化超分子组件，从而产生有效的19F磁共振系统。
Fluorine-19 MRI is increasingly being considered as a tool for biomolecular imaging, but the very poor sensitivity of this technique has limited most applications. Previous studies have long established that increasing the sensitivity of 19F molecular probes requires increasing the number of fluorine nuclei per probe as well as decreasing their longitudinal relaxation time. The latter is easily achieved by positioning the fluorine atoms in close proximity to a paramagnetic metal ion such as a lanthanide(III). Increasing the number of fluorine atom per molecule, however, is only useful in as much as all the fluorine nuclei are chemically equivalent. Previous attempts to achieve this equivalency have focused on designing highly symmetric and rigid fluorinated macrocyclic ligands. A much simpler approach consists of exploiting highly fluxional lanthanide complexes with open coordination sites that have high affinity for phosphated and phosphonated species. Computational studies indicate that LnIII-TREN-MAM is highly fluxional, rapidly interconverting between at least six distinct isomers. In neutral water at room temperature, LnIII-TREN-MAM binds two or three equivalents of fluorinated phosphonates. The close proximity of the 19F nuclei to the LnIII center in the ternary complex decreases the relaxation times of the fluorine nuclei up to 40-fold. Advantageously, the fluorophosphonate-bound lanthanide complex is also highly fluxional such that all 19F nuclei are chemically equivalent and display a single 19F signal with a small LIS. Dynamic averaging of fluxional fluorinated supramolecular assemblies thus produces effective 19F MR systems.
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影响因子：
6.2
作者：
Du, Wenjun;Nystrom, Andreas M.;Zhang, Lei;Powell, Kenya T.;Li, Yali;Cheng, Chong;Wickline, Samuel A.;Wooley, Karen L.
通讯作者：
Wooley, Karen L.
影响因子：
1.7
作者：
Angeli, C;Cimiraglia, R
通讯作者：
Cimiraglia, R
DOI：
10.1007/bf00528565
发表时间：
1989-02-01
期刊：
THEORETICA CHIMICA ACTA
影响因子：
--
作者：
DOLG, M;STOLL, H;PREUSS, H
通讯作者：
PREUSS, H
影响因子：
4.4
作者：
Angeli, C;Cimiraglia, R;Malrieu, JP
通讯作者：
Malrieu, JP
影响因子：
4.4
作者：
Angeli, C;Cimiraglia, R;Malrieu, JP
通讯作者：
Malrieu, JP