Flavanones and 3-hydroxyflavanones from Lonchocarpus oaxacensis

The roots of the tropical tree Lonchocarpus oaxacensis afforded the 3-hydro xyflavanones jayacanol and mundulinol, as well as two flavanones, mundulin and minimiflorin. Flavonoids bearing 6,7-(dimethylpyran) and 8-(gamma gamma -dimethyl allyl) substituents are characteristic for species grouped in th e Minimiflori subsection. Therefore this subsection seems to be chemically and morphologically homogeneous. The antifungal activity of the four isolat ed compounds was tested against the wood rotting fungus Postia placenta, bu t only jayacanol was active. (C) 2000 Elsevier Science Ltd. All rights rese rved.