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An efficient new method for the synthesis of 3-[18 F]fluoro-4-aminopyridine via Yamada-Curtius rearrangement.

ABSTRACT: 4-Aminopyridine is a clinically approved drug to improve motor symptoms in multiple sclerosis. A fluorine-18-labeled derivative of this drug, 3-[18 F]fluoro-4-aminopyridine, is currently under investigation for positron emission tomography (PET) imaging of demyelination. Herein, the Yamada-Curtius reaction has been successfully applied for the preparation of this PET radioligand with a better radiochemical yield and improved specific activity. The overall radiochemical yield was 5 to 15% (n = 12, uncorrected) with a specific activity of 37 to 148 GBq/?mol (end of synthesis) in a 90 minute synthesis time. It is expected that this 1 pot Yamada-Curtius reaction can be used to prepare similar fluorine-18-labeled amino substituted heterocycles.

SUBMITTER: Basuli F

PROVIDER: S-EPMC5992582 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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An efficient new method for the synthesis of 3-[18 F]fluoro-4-aminopyridine via Yamada-Curtius rearrangement.

Basuli Falguni F Zhang Xiang X Brugarolas Pedro P Reich Daniel S DS Swenson Rolf E RE

Journal of labelled compounds & radiopharmaceuticals 20171130 2

4-Aminopyridine is a clinically approved drug to improve motor symptoms in multiple sclerosis. A fluorine-18-labeled derivative of this drug, 3-[18 F]fluoro-4-aminopyridine, is currently under investigation for positron emission tomography (PET) imaging of demyelination. Herein, the Yamada-Curtius reaction has been successfully applied for the preparation of this PET radioligand with a better radiochemical yield and improved specific activity. The overall radiochemical yield was 5 to ...[more]

PMID: 28870001

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