Four unprecedented sulfur-containing cytochalasans,thiocytochalasins A−D(1−4),were isolated from an endophytic fungus Phoma multirostrata XJ-2-1.Thiocytochalasins A(1)and B(2)feature a novel 5/6/14/5 tetracyclic scaff...Four unprecedented sulfur-containing cytochalasans,thiocytochalasins A−D(1−4),were isolated from an endophytic fungus Phoma multirostrata XJ-2-1.Thiocytochalasins A(1)and B(2)feature a novel 5/6/14/5 tetracyclic scaffold,which are the first examples of cytochalasan containing a thiophene moiety.Thiocytochalasins C(3)and D(4)are epimeric cytochalasan homodimers formed via a thioether bridge.Their structures with absolute configurations were established by detailed analysis of the HRESIMS,NMR,and X-ray crystallography.The plausible biogenetic pathway of 1−4 was postulated.Compounds 3 and 4 exhibited significant cytotoxicity against CT26 cells with IC_(50) values of 0.85 and 0.76µmol/L,respectively.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.22077041 and 31770380).
文摘Four unprecedented sulfur-containing cytochalasans,thiocytochalasins A−D(1−4),were isolated from an endophytic fungus Phoma multirostrata XJ-2-1.Thiocytochalasins A(1)and B(2)feature a novel 5/6/14/5 tetracyclic scaffold,which are the first examples of cytochalasan containing a thiophene moiety.Thiocytochalasins C(3)and D(4)are epimeric cytochalasan homodimers formed via a thioether bridge.Their structures with absolute configurations were established by detailed analysis of the HRESIMS,NMR,and X-ray crystallography.The plausible biogenetic pathway of 1−4 was postulated.Compounds 3 and 4 exhibited significant cytotoxicity against CT26 cells with IC_(50) values of 0.85 and 0.76µmol/L,respectively.