Polycyclic Polyprenylated Xanthones from Symphonia globulifera: Isolation and Biomimetic Electrosynthesis
Kevin Cottet1, Anne Neudörffer1, Marina Kritsanida1
1UMR COMETE 8638 CNRS - Université Paris Descartes , Sorbonne Paris Cité, Faculté de Pharmacie de Paris, 4 Avenue de l'Observatoire, 75270 Paris Cedex 06, France.
Abstract:
Two regioisomeric polycyclic xanthones, 3,16-oxyguttiferone A (2) and 1,16-oxyguttiferone A (3), which are polyprenylated acylphloroglucinol-derived analogues, were isolated from the seeds of Symphonia globulifera, together with their presumed o-dihydroxybenzoyl precursor, guttiferone A (1). Anodic oxidation of 1 into the corresponding o-quinone species proved to be an efficient biomimetic method to generate xanthones 2 and 3 in high overall yield and to confirm their structures. Both compounds displayed cytotoxicity against the HCT 116 colon carcinoma cell line with IC₅₀ values of 8 and 3 μM, respectively.
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