Aspartic protease inhibitory and nematocidal activity of phenyl-4-(2-phenylhydrazono)hexahydrofuro[3,2-c]pyridazin-7-ol (Percival dianhydroosazone)

We synthesized Phenyl-4-(2-phenylhydrazono) hexahydrofuro[3,2- c ]pyridazin-7-ol (compound 3). The structure compound 3 was elucidated with IR, 1H NMR, 13C NMR and EIMS spectra. Compound 3 showed potent inhibitory activity against aspartic proteases, human cathepsin D and Plasmodium falciparum plasmepsin-II with IC50 = 20 μM. Enzyme-inhibitor complexes were predicted to stabilize by electrostatic and hydrophobic interactions between the side chains of amino acid residues at the active center and compound 3. Moreover, compound 3 displayed good nematocidal activity against all developmental stages of C. elegans .