Complete on/off responsive ParaCEST MRI contrast agents for copper and zinc
作者:K. Srivastava、G. Ferrauto、S. M. Harris、D. L. Longo、M. Botta、S. Aime、V. C. Pierre
DOI:10.1039/c8dt01172a
日期:——
Two thulium-based ParaCEST responsivecontrastagents, Tm-DOTAm-py and Tm-DOTAm-βAla-py, have been synthesized and evaluated for imaging copper and zinc. Unusual for responsiveMRIcontrastagents, both agents display a complete on/off response in the presence of transition metals. Both complexes function as paraCEST agents in the absence of copper and zinc, with the positively charged Tm-DOTAm-py
已经合成了两种基于Para的ParaCEST响应性造影剂Tm-DOTAm-py和Tm-DOTAm-βAla-py,并对其用于铜和锌的成像进行了评估。对于反应性MRI造影剂而言,这两种试剂不常见,在过渡金属存在的情况下,两种试剂均显示出完整的开/关响应。两种配合物在没有铜和锌的情况下均充当paraCEST试剂,带正电荷的Tm-DOTAm-py比带中性电荷的Tm-DOTAm-βAla-py更敏感。在每种情况下,CEST信号均来自酰胺质子,而不是来自与Tm 3+离子配位的水分子。与Cu +,Cu 2+或Zn 2+结合时,酰胺质子的交换速率大大增加,导致CEST信号完全消失。通过1 / T 1 NMRD谱,17 O NMR测量和分子模拟模拟,证实了这种有效的作用方式以及在存在和不存在过渡金属的情况下都没有内层水分子。这两种络合物都没有铜比锌具有选择性。两者都形成1:1 TmL:Cu +或2:1 TmL:Cu
The effect on the lanthanide luminescence of structurally simple Eu(iii) cyclen complexes upon deprotonation of metal bound water molecules and amide based pendant arms
作者:Sally E. Plush、Naomi A. Clear、Joseph P. Leonard、Ann-Marie Fanning、Thorfinnur Gunnlaugsson
DOI:10.1039/b923383k
日期:——
and their complexes with europium(III) were synthesised. The protonation constants and the metal ion stability constants of two of these ligands were determined by potentiometric titration. The pKa of the water molecules coordinated to the complexed metal ion were determined by both luminescent and potentiometric measurements. The luminescence pH dependence of a further three Eu(III) complexes, 5–7, which
一系列替代 1,4,7,10-四氮杂十二烷配体1-4,具有敏化作用硝基苯 或者 萘 触角,作为酰胺侧基臂之一,及其与 ((III)被合成了。通过电位滴定法测定其中两个配体的质子化常数和金属离子稳定性常数。与配位的金属离子配位的水分子的p K a通过发光和电位测量来确定。另外三个发光的pH值依赖性((III)还研究了没有任何触角的5-7配合物,目的是更好地了解金属结合物的作用水这种分子在直接激发镧系元素离子时具有这种复合物的发光特性。这些发光测量的结果表明,所有配合物的Eu(III)发射均被作为pH的函数进行了调节,我们将其归因于循环系统中离子的配位环境中发生的由金属去质子化引起的变化。边界水 分子和/或酰胺侧臂的去质子化。
Three step vs one pot synthesis and X-ray crystallographic investigation of heptadentate triamide cyclen (1,4,7,10-tetraazacyclododecane) based ligands and some of their lanthanide ion complexes
作者:Thorfinnur Gunnlaugsson、Joseph P Leonard、Sinead Mulready、Mark Nieuwenhuyzen
DOI:10.1016/j.tet.2003.10.086
日期:2004.1
The synthesis of several lanthanide complexes from the tris alkylated cyclen (1,4,7,10-tetraazacyclododecane) ligands 1 and 2 is described. The syntheses of 1 and 2 were investigated by means of two different synthetic routes (Method 1 and Method 2). The first of these involves the mono protection of cyclen using 4-methoxyphenylsulfonyl chloride, followed by alkylation of the remaining three secondary
Delayed lanthanide luminescence sensing of aromatic carboxylates using heptadentate triamide Tb(iii) cyclen complexes: the recognition of salicylic acid in waterElectronic supplementary information (ESI) available: experimental section, Fig. S1, Table S1. See http://www.rsc.org/suppdata/cc/b2/b204888d/
作者:Thorfinnur Gunnlaugsson、Andrew J. Harte、Joseph P. Leonard、Mark Nieuwenhuyzen
DOI:10.1039/b204888d
日期:2002.9.11
The coordinately unsaturated terbium complexes Tb.1 and Tb.2 possess two labile metal-bound water molecules that can be displaced upon metal chelation to aromatic carboxylic anions such as salicylic acid in water, which gives rise to large enhancements in the Tb(III) luminescence.
Luminescent europium sensors for specific detection of 8-oxo-dGTP by time-gated fluorescence
作者:Yasufumi Fuchi、Takashi Fukuda、Shigeki Sasaki
DOI:10.1016/j.bmc.2018.04.052
日期:2018.7
The 9-hydroxy-1,3-diazaphenoxazine-2-one unit was conjugated with the Eu3+-cyclen complex through a linker. This diazaphenoxazine group was expected as an antenna unit for the excitation of europium ion, and a selective recognition site for 8-oxo-dGTP base. Among the synthesized three derivatives, the highest fluorescence emission was obtained by the complex constructed of an ethylene linker and the cyclen unit with three N, N-dimethylacetamide groups. The Eu3+-cyclen complex exhibited a selective response to the 8-oxo-dGTP in aqueous media by a time-resolved fluorescence assay. (C) 2018 Elsevier Ltd. All rights reserved.