Bioactive dihydronaphthoquinone derivatives from Fusarium solani

New dihydronaphthoquinone derivatives, karuquinone A (1), karuquinone B (2), and karuquinone C (3), were isolated from a Fungal culture broth of Fusarium solani. The structures were determined by interpretation of spectroscopic data (1D/2D NMR, MS, and IR). Three known compounds, javanicin (4), 2,3-dihydro-5-hydroxy-8-methoxy-2,4-dimethylnaphtho[1,2-b]furan-6,9-dione (5), and 5-hydroxydihydrofusarubin C (6), were also isolated. The six isolated compounds were tested for cytotoxicity against three human Cancer cell lines and a human umbilical vein endothelial cell (HUVEC) line. Of these, karuquinone A exhibited the strongest cytotoxic activity. Karuquinone B did not affect the proliferation of the Cancer cell lines but did inhibit the proliferation of HUVEC. Additionally, we demonstrated that karuquinone A induces Apoptosis in Cancer cells through the generation of Reactive Oxygen Species (ROS).