Received: 17 August 2022 Accepted: 18 January 2023
Abstract:
Isoandrographolide (2) and its nineteen acetals (3a–3o, 4, 5 and 6a–6b) of which fifteen are new were synthesized and characterized using 1H-NMR, 13C-NMR, mass spectrometry, and IR spectroscopy. The compound 3c was characterized using single-crystal X-ray diffraction as well. All the compounds were tested for their anti-plasmodial potencies (IC50) against the Chloroquine sensitive Pf3D7 and chloroquine resistant PfINDO strains. Potent compounds were further tested also for their cytotoxicity (CC50) against mammalian cells. Compounds 3d (IC50 10.59 µM) and 3e (IC50 12.83 µM) were found to be the most active with mammalian cell CC50 > 100 µM for both the compounds.
Graphical abstract
Keywords: Isoandrographolide; Acetals of isoandrographolide; Semi-synthesis; Malaria; Anti-plasmodial activity; Cytotoxicity