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Synthesis of [²¹¹At]4-astato-L-phenylalanine by dihydroxyboryl-astatine substitution reaction in aqueous solution.

ABSTRACT: Astatine-211 (²¹¹At)-labeled phenylalanine is expected to be a promising agent for targeted alpha-particle therapy for the treatment of patients with glioma. The existing reactions to prepare the labeled compound usually require organic solvents and metals that are toxic and hazardous to the environment. In this study, we developed a novel method wherein astatination was realized via the substitution of ²¹¹At for a dihydroxyboryl group coupled to phenylalanine. [²¹¹At]4-astato-L-phenylalanine was obtained as the carrier-free product in aqueous medium in high radiochemical yields (98.1 ± 1.9%, n = 5). The crude reaction mixture was purified by solid-phase extraction, and the radiochemical purity of the product was 99.3 ± 0.7% (n = 5). The high yield and purity were attributed to the formation of [²¹¹At]AtI and AtI₂^- as the reactive intermediates in the astatination reaction. The reaction did not require any organic solvents or toxic reagents, suggesting that this method is suitable for clinical applications.

SUBMITTER: Shirakami Y

PROVIDER: S-EPMC8217504 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Targeted alpha therapy using astatine (211At)-labeled phenylalanine: A preclinical study in glioma bearing mice.

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Manual on the proper use of meta-[211At] astato-benzylguanidine ([211At] MABG) injections in clinical trials for targeted alpha therapy (1st edition).

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Pre-clinical investigation of astatine-211-parthanatine for high-risk neuroblastoma.

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