Synthesis of racemic (+) and (-) N-[methyl-11C]nomifensine, a ligand for evaluation of monoamine re-uptake sites by use of positron emission tomography.
The synthesis of racemic or enantiomeric N-[methyl-11C]nomifensine (1,2,3,4-tetrahydro-2-[11C]methyl-4-phenyl-8-isoquinolinamine), a potential ligand for the evaluation of monoamine re-uptake sites at the presynaptic dopaminergic terminals, using the appropriate N-desmethylcompounds and [11C]methyl iodide is described. The radiochemical conversion of [11C]methyl iodide to [11C]nomifensine was in the order of 85-95%. Radiochemical purity of the LC-purified radiopharmaceutical was in the order of 98-99%. In a typical run, starting with 120 mCi (4.4 GBq) of [11C]carbon dioxide, 380 MBq (8.6% not decay corrected) of a final solution was obtained within 55 min (roughly 20 min of that is related to transport time). The specific radioactivity corresponding to the [11C]methyl iodide was 30-100 mCi/mumol (typical: a total mass of 30 micrograms and 150 MBq was administered in the PET-studies). A procedure for resolving the racemate of N-desmethylnomifensine (1,2,3,4-tetrahydro-4-phenyl-8-isoquinoline) into its enantiomers using triacetylcellulose as the stationary phase and methanol/ethanol as solvents by use of LC is also described.
Ulin
J
J
Department of Organic Chemistry, University of Uppsala, Sweden.
Gee
A D
AD
Malmborg
P
P
Tedroff
J
J
Långström
B
B
D000328:Adult; D015306:Biogenic Monoamines / Q000493:pharmacokinetics*; D002250:Carbon Radioisotopes; D006801:Humans; D007553:Isotope Labeling / Q000379:methods*; D008024:Ligands; D008875:Middle Aged; D009627:Nomifensine / Q000138:chemical synthesis*; D011954:Receptors, Dopamine / Q000378:metabolism*; D014055:Tomography, Emission-Computed
D015306:Biogenic Monoamines; D002250:Carbon Radioisotopes; D008024:Ligands; D011954:Receptors, Dopamine; D009627:Nomifensine