Planta Med 2007; 73 - P_105
DOI: 10.1055/s-2007-986887

Cyclic Heptapeptides from the latex of Jatropha integerrima

J Conrad 1, W Mongkolvisut 2, S Sutthivaiyakit 2, H Leutbecher 1, S Mika 1, I Klaiber 3, W Möller 4, H Rösner 4, U Beifuß 1
  • 1Institute of Chemistry, Hohenheim University, Garbenstraße 30, 70599 Stuttgart, Germany
  • 2Department of Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok 10240, Thailand
  • 3Institute of Physiology, Hohenheim University, August-von-Hartmann-Straße 2, 70599 Stuttgart, Germany
  • 4Institute of Zoology, Hohenheim University, Garbenstraße 30, 70599 Stuttgart, Germany

Jatropha species (Euphorbiaceae) are known to be a rich source of bioactive diterpenes and cyclic peptides. [1] In the course of our phytochemical investigations of J. integerrima we isolated two new cylic heptapeptides, namely integerrimide A (1) and B (2), from the latex of J. integerrima [2]. The structures of 1 and 2 (both existing as equilibrium mixtures of different conformers) were elucidated by extensive 1D, sel-1D, and 2D NMR studies, MS, as well as chemical degradation. In a screening on basic cytoskeleton- dependent cellular processes (neurite outgrowth, cell proliferation, cell migration) both compounds (50µM each) showed a significant inhibition of neurite outgrowth of E7 chicken spinal cord neurons as well as an antiproliferation (up to 40% lower cell densities after 2 days) but no cytotoxic activity on human melanoma cells (IPC-298). Standard cell migration assay (SMA) with confluent human pancreatic carcinoma cells (Capan II) revealed an inhibition of cell migration by about 30 and 20% of 1 and 2 (50µM each), respectively.

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References: [1] Sutthivaiyakit, S. et al. (2003) Tetrahedron Lett. 44: 3637–3640. [2] Mongkolvisut, W. et al. (2006) J. Nat. Prod. 69: 1435–1441.