Two new cytochalasan derivatives from Chaetomium globosum SNSHI-5, a fungus derived from extreme environment.

Two new cytochalasan derivatives, isochaetoglobosin Db (1) and cytoglobosin Ab (2), were isolated from an ethyl acetate extract of Chaetomium globosum SNSHI-5, a fungus derived from extreme environment. The structures of the new compounds were comprehensively characterized by HR-ESI-MS, 1H NMR, 13C NMR and 2D-NMR. Cytotoxic activity against H292 human lung cancer cell of the new compounds was tested. Isochaetoglobosin Db (1) showed potent cytotoxicity with IC50 of 3.5 μM, while cytoglobosin Ab was inactive (IC50 > 10 μM).