与胺或氧基组作为ParaCEST剂添加的四亚马克环复合物
Jaclyn J Raymond1, Samira M Abozeid1, Gregory E Sokolow1
1Department of Chemistry, Natural Sciences Complex, University at Buffalo, the State University of New York, Amherst, NY 14260, USA. jmorrow@buffalo.edu.
Dalton transactions (Cambridge, England : 2003)
|July 4, 2023
概括
基于四亚宏循环的新复合物显示出其作为超磁性化学交换和转移 (paraCEST) 剂的前景. 基于CYCLAM的复合物与胺悬挂物表现出最强烈的CEST效应,这表明进一步开发的潜力.
科学领域:
- 协调化学 协调化学
- 超分子化学 超分子化学
- 磁共振成像 (MRI) 对比剂对比剂
背景情况:
- 偏磁化学交换和转移 (paraCEST) 剂对于先进的MRI应用至关重要.
- 由于其稳定性和可调节性特性,四亚马克环 (Tetraazamacrocyclic cobalt) 复合物具有作为新型ParaCEST剂的潜力.
- 了解这些复合体的结构和动态行为是优化其CEST性能的关键.
研究的目的:
- 合成和表征新型 ((II) 复合物与带有悬挂组的四亚马克罗环联体 (CYCLEN和CYCLAM).
- 评估这些复合物的潜力作为超磁性化学交换和转移 (paraCEST) 剂.
- 研究影响这些金属复合体中CEST效应的结构性质关系.
主要方法:
- 合成 (II) 复合物与CYCLEN和CYCLAM连接物,其功能化与氧或胺.
- 单晶X射线衍射以确定固态结构和坐标数.
- 质子核磁共振 (1H NMR) 谱学用于研究溶液行为和异构性.
- 化学交换和转移 (CEST) 光谱法用于评估paraCEST属性.
- 对解离和传播的惰性研究.
主要成果:
- 六坐标和七坐标 (II) 复合体的结构特征是.
- 溶液NMR揭示了不同的动态行为,包括流动性和全吊组协调.
- 观察到CEST效应,主要归因于悬挂的NH或OH质子.
- 基于CYCLAM的复合物与胺悬挂显示出最强烈和高度移动的CEST峰值.
- 所有合成的复合物都在缓冲溶液中表现出极好的稳定性和抗转移性.
结论:
- 四亚宏环复合体的结构和动态特性显著影响它们的paraCEST能力.
- 由于强烈的,转移的CEST信号,CYCLAM复合物与悬浮胺基组对于paraCEST应用特别有前途.
- 这些稳定复合体为下一代paraCEST代理的合理设计提供了宝贵的见解.
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