A series of 30 6-chloro-2, 4-diaminopyrimidines was synthesized and tested in vitro as inhibitors of [3H] spiroperidol binding. The affinity for the dopamine receptor was shown to be related to the 6-chloro-4-(N-methylpiperazine) pyrimidine structure bearing a NH2 or NHRl group as a substituent in position 2, provided that R1 was not an a branched alkyl group. The nature of the substituent in position 5 is also of importance for the affinity; 2-( ...
