Design, Synthesis, and Development of Novel Guaianolide-Endoperoxides as Potential Antimalarial Agents

Design and synthesis of a guaianolide-endoperoxide (thaperoxide) 3 was pursued as a new antimalarial lead which was found to be noncytotoxic as compared to the natural product lead thapsigargin 2. Several analogues of 3 were successfully synthesized and found to be comparable to derivatives of artemisinin 1 in in vitro antimalarial assay. Among the synthesized compounds, 22 showed excellent in vitro potency against the cultured parasites (W2 IC50 = 13 nM) without apparent cytotoxicity. Furthermore, SAR trends in thaperoxide analogues are presented and explained with the help of docking studies in the homology model of PfSERCA(PfATP6).