in this study , the highest plasma alkaloid concentrations were reached with quinidine and the lowest concentrations with the quinidine congener , cinchonine . the other congeneric pair , quinine and cinchonidine , exhibited plasma alkaloid concentrations that were comparable and intermediate to those of quinidine and cinchonine . with cinchonine and cinchonidine , the plasma and blood concentration-time curves were virtually superimposable .
C0034417
quinine
C0034414
quinidine