Planta Med 2008; 74 - P-82
DOI: 10.1055/s-2008-1075278

Antiproliferative Compounds of Helmiopsis sphaerocarpa from the Madagascar Rainforest

S Cao 1, P Brodie 1, JS Miller 2, C Birkinshaw 3, A Rakotondrafara 3, R Andriantsiferana 4, VE Rasamison 4, DGI* Kingston 1
  • 1Department of Chemistry, M/C 0212, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061-0212, USA
  • 2Missouri Botanical Garden, P.O. Box 299, St. Louis, Missouri 63166-0299, USA
  • 3Missouri Botanical Garden, BP 3391, Antananarivo 101, Madagascar
  • 4Centre National d'Application des Recherches Pharmaceutiques, B.P. 702, Antananarivo 101, Madagascar

Bioassay-directed separation of an ethanol extract of the leaves of Helmiopsis sphaerocarpa L.C. Barnett (Sterculiaceae) led to the isolation of five compounds: 14,15-α-epoxy-3-β-hydroxytaraxerane (1), taraxerol (2), stimast-5-en-3-ol (3), 5ʹ,8ʹ-epidioxy-24(S)-methylcholesta-6,22-dien-3β-ol (4), and 24ξ-hydroperoxy-24-ethylcholesta-4,28(29)-dien-3-one (5). The structure of the new compound 1 was established on the basis of interpretation of its 1D and 2D NMR spectroscopic data. All the compounds were tested against A2780 human ovarian cancer cell lines, and only 4 and 5 showed mild activity with IC50 values of 16 and 7 µg/mL, respectively. Acknowledgements: This project was supported by the Fogarty International Center, the National Cancer Institute, the National Science Foundation, the National Heart, Lung and Blood Institute, the National Institute of Mental Health, the Office of Dietary Supplements, and the Office of the Director of NIH, under Cooperative Agreement U01 TW000313 with the International Cooperative Biodiversity Groups, and this support is gratefully acknowledged.