Planta Med 2015; 81 - PX43
DOI: 10.1055/s-0035-1556487

Four antimalarial limonoids isolated from Carapa guianensis and two antiproliferative diterpenes isolated from Hypoestes SP.

M Wang 1, P Krai 2, S Dala 2, M Cassera 2, M Goetz 3, S Rakotonandrasana 4, VE Rasamison 4, DGI Kingston 1
  • 1Department of Chemistry and Virginia Tech Center for Drug Discovery, Virginia Tech, Blacksburg, VA 24061 USA
  • 2Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061 USA
  • 3Natural Products Discovery Institute, 3805 Old Easton Road, Doylestown, PA, 18902, USA
  • 4Centre National d'Application de Recherches Pharmaceutiques, Antananarivo, Madagascar

In a search for antimalarial natural products from plants in collaboration with the Natural Products Discovery Institute we investigated an antiplasmodial extract from Carapa guianensis (Meliaceae). This extract gave a DCM fraction with activity against the chloroquine-resistant Dd2 strain of P. falciparum with an IC50 value about 4 µg/mL. The four active limonoids (1 – 4) were isolated from this fraction and their structures were elucidated by 1D and 2D NMR spectroscopic and MS data. This is the first report of the antimalarial activity of 6α,11β-diacetoxygedunin (1). In a separate study as part of our work in the Madagascar International Cooperative Biodiversity Group program, two diterpenes with good antiproliferative activity against the A2780 human ovarian cancer cell line as well as antimalarial activity were found in the hexanes fraction from the extract of Hypoestes sp. (Acanthaceae). This is the first report of the activity of crotonolide G (5) towards A2780 cell lines and of its antiplasmodial activity.

IC50 (P. falciparum Dd2) µM

IC50 (A2780)µM

1 IC50 = 2.0 ± 0.3

5 IC50 = 9.9 ± 1.4

5 ˜2

2 IC50 = 2.1 ± 0.1

6 IC50 = 2.8 ± 0.7

6 1.1

3 IC50 = 2.1 ± 0.2

4 IC50 = 2.8 ± 0.2