Curvulomycin E, a New Resorcylic Acid Lactone From the Beibu Gulf Coral‐Derived Fungus Curvularia lunata GXIMD 02512

ABSTRACT One new resorcylic acid lactone (RAL), curvulomycin E ( 1 ), along with 10 known compounds ( 2 – 11 ), was obtained from the Beibu Gulf coral‐derived fungus Curvularia lunata GXIMD 02512. Their structures were determined by extensive spectroscopic data interpretation and comparison with literature. The absolute configurations of 1 and 10 were accomplished by ECD calculations. Structurally, curvulomycin E ( 1 ) with a methoxy substituent at C‐12 is generally uncommon in the 12‐membered RAL family. Compounds 2 – 4 exhibited cytotoxicity against MDA‐MB‐231 and KTC‐1 cells with IC 50 values ranging from 10.8 to 26.5 μM. The preliminary structure–activity relationship is discussed. Compound 2 further arrested the cell cycle at the S phase and dose‐dependently induced apoptosis in MDA‐MB‐231 cells.