Six New Derivatives from Alternaria sp MCCC 3A00467

Terrestrial plant resources are becoming increasingly scarce; moreover, the development of science and technology has facilitated the exploration of marine ecosystems. We isolated and identified six novel (1–6) and six (7–12) known secondary metabolites of Alternaria sp MCCC 3A00467 by chromatographic and spectroscopic techniques and investigated their antitumor activities in human myeloma (U266), liver cancer (HepG2), and lung cancer (A549) cells by the MTT assay. Among these compounds, the new compounds 2, 3 and 4 exhibited excellent anticancer activities with IC50 values of 21.98, 24.99 and 14.78 μg/mL, respectively. These compounds obtained from a marine source have the potential to be developed into novel anticancer drugs.