Chemotherapy of leishmaniasis part X: Synthesis and bioevaluation of novel terpenyl heterocycles

Some novel α and β ionone based chalcones and their dihydropyrazolidines/pyrazolidines have been synthesized and evaluated for their in vitro and in vivo antileishmanial activities against Leishmania donovani. Amongest all, one compound (4d) exhibited significant in vitro activity against intracellular amastigotes of Leishmania donovani with IC50 values of 7.49 μM and was found promising as compared to reference drug, miltefosine. On the basis of good Selectivity Index (S.I.), the compound was further tested for its in vivo response against Leishmania donovani/hamster model and has shown significant inhibition of parasite multiplication (81%). The present study has helped us in identifying a new lead that could be exploited as a potential antileishmanial agent.