No-carrier-added regioselective preparation of 6-[18F]fluoro-L-dopa

J Nucl Med. 1990 Jul;31(7):1247-51.

Abstract

This paper describes the preparation of 6-[18F]fluoro-L-dopa by a no-carrier-added method based on the nucleophilic displacement of nitro groups of two commercially available substrates, 3,4-dimethoxy-2-nitrobenzaldehyde (nitroveratraldehyde) and 6-nitropiperonal. Fluorination was conducted in DMSO with fluorine-18 (18F) in the presence of the aminopolyether Kryptofix 222 and potassium carbonate. The condensation of the fluorinated aldehydes with phenyloxazolone and the subsequent hydrolysis with HI/P yield, after purification by HPLC, only the 6-(D, L) isomers. The racemic mixture (50/50) was resolved on an analytical scale chiral column. The method, which requires 100 min (EOB) to complete, produces 6-[18F]fluoro-L-dopa with a decay-corrected radiochemical yield of 10%, an enantiomeric purity greater than 99%, and a specific activity of 1.2 Ci/mumole.

MeSH terms

  • Benzaldehydes
  • Chromatography, High Pressure Liquid
  • Dihydroxyphenylalanine / analogs & derivatives*
  • Dihydroxyphenylalanine / chemical synthesis
  • Dimethyl Sulfoxide
  • Fluorine Radioisotopes
  • Hydrolysis

Substances

  • Benzaldehydes
  • Fluorine Radioisotopes
  • nitroveratraldehyde
  • fluorodopa F 18
  • Dihydroxyphenylalanine
  • 6-nitropiperonal
  • Dimethyl Sulfoxide