Amide conjugates of the DO3A-N-(α-amino)propionate ligand: leads for stable, high relaxivity contrast agents for MRI?
نویسندگان
چکیده
A novel synthetic methodology for preparing amide conjugates of the DO3A-N-(α-amino)propionate chelator is described, using the synthesis of the DO3A-N-(α-benzoylamido)propionate chelator as an illustrative example. The model Gd[DO3A-N-(α-benzoylamido)propionate] chelate displays accelerated water exchange, stability in a wide pH range and inertness towards transmetallation by Zn(2+). The Gd[DO3A-N-(α-benzoylamido)propionate] complex is mainly excreted via the kidneys, producing a significant increase in the kidney medulla/cortex enhancement ratio in MR images of Wistar rats, reflecting probably its higher lipophilicity compared with Gd(DTPA). The results presented suggest that Gd[DO3A-N-(α-amido)propionate] chelates can be valuable leads for preparing potentially safe high relaxivity MRI contrast agents.
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عنوان ژورنال:
- Contrast media & molecular imaging
دوره 8 1 شماره
صفحات -
تاریخ انتشار 2013