Abstract

Nucleophilic copper-mediated radioiodination (CMRI) of organoboronic precursors with radioiodides is a promising method of radioiodination. The previously reported CMRI has demonstrated its great potential and scope of labeling for the radiosynthesis of radioiodine-labeled compounds. However, the reported protocols (using a small amount/volume of radioactivity) are practically not reproducible in large-scale CMRI, in which the radioactivity was usually provided in a bulk alkaline solution. A large amount of water and a strong base are incompatible with CMRI. To overcome these issues in large-scale CMRI, we have developed a simple protocol for large-scale CMRI. The bulk water was removed under a flow of inert gas at 110°C, and the strong base (i.e., NaOH) was neutralized with an acid, pyridinium p-toluenesulfonate or p-toluenesulfonic acid. In the model reactions of [123 I]KX-1, a PARP-1 radioligand for Auger radiotherapy, radiochemical conversions were significantly improved after neutralization of the base, and the addition of additional acids was tolerated and favorable for the reactions. Using this protocol, [123 I]KX-1 was radiosynthesized from 20 mCi (0.74 GBq) of [123 I]iodide in high radiochemical yields, high radiochemical purity, and high molar activity. This protocol should be applicable to the radiosynthesis of other compounds with radioiodine via CMRI.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call