New naphthoquinone derivatives from Fusarium napiforme of a mangrove plant.

Two new naphthoquinone derivatives, 6-hydroxy-astropaquinone B ( 1 ) and astropaquinone D ( 2 ) as well as the known compound 3- O -methyl-9- O -methylfusarubin ( 3 ) were isolated from Fusarium napiforme , an endophytic fungus isolated from the mangrove plant, Rhizophora mucronata . The structures of 1 and 2 were determined by 1D and 2D NMR spectroscopic analyses. Compounds 1 , 2 and 3 exhibited moderate antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa . Furthermore, 1 , 2 and 3 were phytotoxic action in lettuce seeding at a concentration of 30 μg · mL ^-1 .