Cytotoxic Alkaloids from Fusarium incarnatum Associated with the Mangrove Tree Aegiceras corniculatum

Several unusual alkaloids, N-2-methylpropyl-2-methylbutenamide (1), 2-acetyl-1,2,3,4-tetrahydro-beta-carboline (2), fusarine (3), fusamine (4), and 3-(1-aminoethylidene)-6-methyl-2H-pyran-2,4(3H)-dione (5), were isolated from the culture broth of Fusarium incarnatum (HKI0504), an endophytic fungus of the mangrove plant Aegiceras corniculatum. Compounds 2, 4, and 5 exhibit weak antiproliferative and cytotoxic activities against HUVEC, K-562, and HeLa human cell lines, respectively.