Secondary metabolites of Diaporthe sp., isolated from the Cameroonian medicinal plant Trema guineensis (Schumach. & Thonn.) Ficalho

From a fresh root of Trema guineensis (Ulmaceae), endophytic fungi were isolated, among which a taxon belonging to Diaporthe sp. This strain was fermented in shake flask batch cultures and the broth extracted with ethyl acetate. From the crude extract, a hemiketal polyketide ( 1 ), and an acetylated alternariol ( 2 ) were isolated, along with fifteen known secondary metabolites. Their structures were established by extensive NMR spectroscopy and mass spectrometry analyses, as well as by comparison with literature data of their analogs.