Rhinoclactones A-E, Resorcylic Acid Analogs from Desert Plant Endophytic Fungus .

Seven resorcylic acid lactones (RALs) including five new analog rhinoclactones, A-E (, , -), were isolated from an endophytic fungus in the plant collected from the Tengger Desert of the Ningxia Province, China. The structures of these new compounds were determined by HR-ESI-MS (High Resolution Electrospray Ionization Mass Spectrometry), NMR data, modified Mosher's method, and X-ray diffraction experiments. All compounds isolated from this fungus possessed the 16-OMe/14-OH, not the common 16-OH/14-OH or 16-OH/14-OMe groups on the aromatic ring, which are rarely found in nature. Compound displayed cytotoxic activities against HCT116 and HeLa cancer cell lines. The possible biosynthesis of - is suggested, and the potential ecological roles of these fungal secondary metabolites is discussed.