Synthesis of stable isotope-labeled chloroquine and amodiaquine and their metabolites.

Anti-malaria drugs chloroquine and amodiaquine and their metabolites were synthesized to incorporate 13 C and 15 N starting from U-13 C-labeled benzene to give M + 7 isotopomers. Chloroquine and its metabolites were prepared from 7-chloro-1,2,3,4-tetrahydroquinolin-4-one through an aryl substitution with the corresponding amines; and the amodiaquine and its metabolites were prepared from 4,7-dichloroquinoline in a similar fashion.