Withanolides from Three Species of the Genus Deprea (Solanaceae). Chemotaxonomical considerations

Abstract

Nine withanolides were isolated from the aerial parts of Deprea bitteriana, Deprea cuyacensis, and Depreazamorae. D. bitteriana yielded two withaphysalins, D. cuyacensis gave two 13,14-seco withaphysalins,while D. zamorae yielded five physangulidines. The compounds were fully characterized by a combinationof spectroscopic methods (1D and 2D NMR and MS). All compounds isolated from D. bitterianaand D. cuyacensis were obtained as epimeric mixtures at C-18. The structure of physangulidine D wasconfirmed by X-ray diffraction analysis. The skeletons found in this research support the chemotaxonomicalposition of the genus Deprea in the tribe Physalideae.