The antiplasmodial activity of norcantharidin analogs

The antiplasmodial activities of sixty norcantharidin analogs were tested in vitro against a chloroquine sensitive (D6, Sierra Leone) and chloroquine resistant (W2) strains of Plasmodium falciparum. Forty analogs returned IC50 values <500 μM against at least one of the P. falciparum strains examined. The ring open compound 24 ((1S,4R)-3-(allylcarbamoyl)-7-oxabicyclo[2.2.1]heptane-2-carboxylic acid) is the most active aliphatic analog (D6 IC50 = 3.0 ± 0.0 and W2 IC50 = 3.0 ± 0.8 μM) with a 20-fold enhancement relative to norcantharidin. Surprisingly, seven norcantharimides also displayed good antiplasmodial activity with the most potent, 5 returning D6 = 8.9 ± 0.9 and W2 IC50 = 12.5 ± 2.2 μM, representing a fivefold enhancement over norcantharidin.

The antiplasmodial activity of 60 norcantharidin analogs is reported.Figure optionsDownload as PowerPoint slide