Pchaeglobolactone A, Spiropchaeglobosin A, and Pchaeglobosals A and B: Four Rearranged Cytochalasans from Chaetomium globosum P2-2-2

Four novel rearranged cytochalasans ( 1 – 4 ) were isolated from an endophytic fungus Chaetomium globosum P2-2-2. Pchaeglobolactone A ( 1 ) possessed an unprecedented 13-aza-21-oxa-tetracyclo-[10.6.1.2 17,19 .0 15,19 ]henicosane core. Spiropchaeglobosin A ( 2 ) was the first example of cytochalasans featuring a novel spiro[5.10]hexadecane unit. Pchaeglobosals A ( 3 ) and B ( 4 ) featured a unique 5/5/13 fused tricyclic ring system. Compounds 1 – 4 were tested for their antiproliferative, apoptosis, cell cycle arrest, and TRAIL-resistance-overcoming activities on cancer cell lines.