Ehrin E, Farde L, de Paulis T, Eriksson L, Greitz T, Johnström P, Litton J E, Nilsson J L, Sedvall G, Stone-Elander S
Int J Appl Radiat Isot. 1985 Apr;36(4):269-73. doi: 10.1016/0020-708x(85)90083-3.
A new dopamine receptor antagonist, Raclopride (S-(-)-3,5-dichloro-N-[(1-ethyl-2-pyrrolidinyl)]methyl-2-hydroxy- 6-methoxybenzamide, FLA 870) (1), has been labelled using [11C]ethyl iodide for alkylation of the nitrogen of the pyrrolidine ring in the corresponding secondary amine (5). The synthesis of 5 and an efficient method for the preparation of [11C]ethyl iodide are described. The 11C-labelled FLA 870 (1) was purified by HPLC and then used in positron emission tomography to visualize the dopamine receptor-rich areas of the monkey brain. The images obtained show selective accumulation of FLA 870 in striatum and a 10-fold separation between the binding to caudate vs cerebellum.
