Anti-Pneumocystis carinii and antiplasmodial activities of primaquine-derived imidazolidin-4-ones

A series of primaquine-derived imidazolidin-4-ones were screened for their in vitro activity against Pneumocystis carinii and Plasmodium falciparum W2 strain. Most compounds were active against P. carinii above 10 μg/mL and displayed slight to marked activity. The imidazolidin-4-ones most active against P. carinii were also those most active antiplasmodial agents, in the μM range. One of the tested imidazolidin-4-ones was slightly more active than the parent primaquine and may represent a lead compound for the development of novel anti-P. carinii 8-aminoquinolines with increased stability and resistance to metabolic inactivation.

The anti-Pneumocystis carinii and antiplasmodial activities of compounds 2 were evaluated and found to be correlated. Cycloheptanone-derived imidazolidin-4-ones 2g, 2j–k (R2 and R3 = –(CH2)6–) were the most active.Figure optionsDownload as PowerPoint slide