对六个协调的Co (II) 和Ni (II) 复合体的pyridine-tetraamide基连接体对paraCEST反应的研究
Suvam Kumar Panda1, Ankit Rai1, Akhilesh Kumar Singh1
1Indian Institute of Technology Bhubaneswar, Khordha, Odisha, 752050, India. aksingh@iitbbs.ac.in.
Dalton transactions (Cambridge, England : 2003)
|November 27, 2023
概括
研究人员合成了一种新的配体,PATA,及其Co (II) 和Ni (II) 复合体. [Co(PATA) ]2+复合体显示出有前途的paraCEST活动,在各种条件下显示出稳定性和强烈的反应.
科学领域:
- 协调化学 协调化学
- 超分子化学 超分子化学
- 生物医学成像代理商 生物医学成像代理商
背景情况:
- 新型配体和金属复合物的开发对于医疗成像中的对比剂的发展至关重要.
- 偏磁化学交换和转移 (paraCEST) 剂在MRI中提供了增强灵敏度和特异性的潜力.
- 研究了PATA连接体及其金属复合物,以确定它们作为paraCEST代理物的潜力.
研究的目的:
- 为了合成和表征一种新型的配体,PATA (2,2',2'',2'''-((pyridine-2,6-diylbis(methylene)) bis(azanetriyl)) tetraacetamide),以及其Co(II) 和Ni(II) 复合物.
- 评估合成复合物的结构特征和paraCEST活动.
- 在各种生理条件下评估有希望的[Co(PATA) ]2+复合物的稳定性和性能.
主要方法:
- 联结体和金属复合物的合成.
- 用X射线衍射进行结构确定.
- 使用溶液状态磁性和氧化还原性质研究进行表征.
- 在不同的温度,pH值和竞争性离子的存在下进行paraCEST测量.
主要成果:
- 成功合成了PATA配体及其Co (II) 和Ni (II) 复合体.
- [Co(PATA) ]2+呈现出扭曲的八面体几何形状,并显示出显著的paraCEST活动.
- [Co(PATA) ]2+在酸性条件,高温和生理pH下表现出极好的稳定性.
- 在37°C和25°C观察到对[Co(PATA) ]2+的高paraCEST反应.
- 由于快速的水质质子交换,[Ni(PATA) ((OH2) ]2+复合体是不活跃的.
结论:
- 由于其结构完整性和强大的性能,[Co(PATA) ]2+复合体是基于paraCEST的成像剂的有希望的候选者.
- PATA联体为开发稳定有效的金属基对比剂提供了合适的支架.
- 基于类似的连接体结构优化paraCEST代理的进一步研究是合理的.
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