IN-VITRO ACTION OF ENT-MANOYL OXIDES AGAINST LEISHMANIA-DONOVANI

Several ent-manoyl oxides obtained from natural products through chemi cal and microbiological procedures were tested in vitro as inhibitors of the growth of the promastigote and amastigote forms of leishmania d onovani. Compounds 3, 6, 7, and 15 showed significant antileishmanial activity. (3S)-ent-3 beta-Acetoxy-12-oxo-8 alpha,13-epoxylabda-9,14-di ene (15), whose semisynthesis is described, totally inhibited the prom astigote forms of L. donovani at a concentration of 100 mg/mL after 24 h of incubation. Functionalization of this series of compounds plays an important role in the antileishmanial activity observed.