Chemical constituents and cytotoxic activity from the wood-decaying fungus Xylaria sp. SWUF08-37.

A new cyclic pentapeptide, pentaminolarin ( 1 ), and a new cytochalasin, xylochalasin ( 2 ), along with thirteen known compounds ( 3 - 15 ) were isolated from the wood-decaying fungus Xylaria sp. SWUF08-37. The absolute configurations of 1 were determined by a combination of Marfey's method and TDDFT ECD calculation and the absolute configurations of 2 were established by TDDFT ECD calculation. Compound 12 showed moderate cytotoxicity against HeLa (IC ₅₀  = 19.60 µg/mL), HT29 (IC ₅₀  = 17.31 µg/mL), HCT116 (IC ₅₀  = 14.28 µg/mL), MCF-7 (IC ₅₀  = 15.38 µg/mL), and Vero (IC ₅₀  = 24.97 µg/mL) cell lines by MTT assay. Compounds 1 and 2 showed slight cytotoxicity against all tested cancer cell lines.