Planta Med 2008; 74 - PB161
DOI: 10.1055/s-0028-1084505

Onobrychis species: a source of novel C-prenylated cytotoxic 3-formyl-2-arylbenzofurans

M Halabalaki 1, X Alexi 2, N Aligiannis 1, E Kalpoutzakis 1, MN Alexis 2, AL Skaltsounis 1
  • 1Division of Pharmacognosy and Natural Products Chemistry, School of Pharmacy, University of Athens, Panepistimioupoli Zografou, 15771, Athens, Greece
  • 2Molecular Endocrinology Program, Institute of Biological Research and Biotechnology, National Hellenic Research Foundation, GR-11635 Athens, Greece

The genus Onobrychis belongs to Leguminosae family and contains over 160 species which are widespread in Europe, the Americas, W. Asia and N. Africa [1]. The phytochemical reports concerning the genus are limited and mainly referred to O. viciifolia due to its great economic importance [2]. In the continued study of Leguminosae plants, 5 different species of the genus Onobrychis were investigated (O. ebenoides, O. alba ssp. alba, O. caput-galli, O. aequidentata and O. montana ssp. scardica). The plants extracts were analyzed qualitatively (TLC & HPLC-PDA) and explored biologically (E-screen assay). All the MeOH extracts found to be estrogenic. The extracts of O. ebenoides were the richest regarding their phytochemical profile and were selected to be further investigated. A number of secondary metabolites were isolated and structurally characterized using several chromatographic (LC, MPLC, HPLC) and spectroscopic techniques (UV, MS, 1&2D NMR), respectively. From the isolated compounds 3 are 2-arylbenzofurans (2 novel compounds), 9 are 3-formyl-2-arylbenzofurans (9 novel compounds), 4 are isoflavones (1 novel compound), 2 are coumestans (1 novel compound), 1 is a pterocarpan (a novel compound) and 2 are flavonoid diglucosides [3]. In addition, a number of simple phenolics, sterols and cyclitoles were isolated and characterized. Numerous of biological assays were performed in order to evaluate the biological activities of the isolated 2-arylbenzofurans and isoflavones. Both showed an important estrogenic activity while the prenylated 3-formyl-2-arylbenzofurans appeared to be selectively cytotoxic to multiple cancer cell lines [4,5].

References: 1. Tutin, TG. (1972), Flora Europaea, University Press, Cambridge, U.K. 2. Jones, BA. (1995) Journal of Science, Food and Agriculture, 67:109–112. 3. Halabalaki, M. et al. (2000)J. Nad. Prod. 63:1672–674. 4. Halabalaki, M. et al. (2006) Planta Medica 72:488–493. 5. Katsanou, ES. et al. (2007)J Steroid Biochem Mol Biol. 104:228–36.