Synthesis of a fluorinated fatty acid, dl-erythro-9,10-[18F]difluoropalmitic acid, and biodistribution studies in rats.
9,10-Difluoropalmitic acid (DFPA) labeled with the cyclotron produced, positron emitting radionuclide 18F has been synthesized as a potential analogue of 9,10-[3H]palmitic acid, a fatty acid which has been used to study lipid metabolism in rat brain and pituitary. [18F]DFPA was prepared by the direct and stereoselective addition of [18F]F2 to the double bond of cis-9,10-palmitoleic acid. The fluorination was carried out in FCCl3 at -70 degrees C using a low concentration of F2 (0.5%) in neon. [18F]DFPA has been obtained in radiochemical yields of 12-16% from end-of-bombardment (EOB) in approx. 2.5 h. Chemical and radiochemical purity exceeded 95%, and specific activities calculated to EOB ranged from 500 to 1000 mCi/mmol. [18F]DFPA crosses the blood-brain barrier and is incorporated into rat brain at about twice the level of that of 9,10-[3H]palmitic acid. The synthesis of [18F]DFPA permits us to study the biological disposition and metabolism of a vicinal-difluoro fatty acid.
Schmall
B
B
Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, NIA, National Institutes of Health, Bethesda, MD 20892.
Finn
R D
RD
Rapoport
S I
SI
Noronha
J G
JG
DeGeorge
J J
JJ
Kiesewetter
D O
DO
Simpson
N R
NR
Larson
S M
SM
D000818:Animals; D010169:Palmitic Acids / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D051381:Rats; D011916:Rats, Inbred F344; D014018:Tissue Distribution; D014316:Tritium
D010169:Palmitic Acids; D014316:Tritium; C067999:9,10-difluoropalmitic acid