Four spiroquinazoline alkaloids from Eupenicillium sp. isolated as an endophytic fungus from leaves of Murraya paniculata (Rutaceae)

A Eupenicillium spp. was isolated from healthy leaves of Murraya paniculata (Rutaceae) after surface sterilization. This fungus was cultivated in sterilized white-corn, where the spiroquinazoline alkaloids alanditrypinone, alantryphenone, alantrypinene and alantryleunone were produced. The culture was extracted with methanol and the alkaloids were isolated by a combination of silica gel chromatography and HPLC. The structures were elucidated by extensive spectroscopic studies, including 2D NMR and MS-MS experiments. The possible role of endophytes in the biosynthesis of plant secondary metabolites is discussed.