Metabolites of the higher fungi. Part 26. Cubensic acid, 3,7,11,15-tetra hydroxy-18-(hydroxymethyl)-2,4,6,10,14,16,20-heptamethyldocosa-4E,8E,12E,16E-tetraenoic acid, a novel polysubstituted C22 fatty acid from the fungus Xylaria cubensis(Mont.) Fr. with substituents and substitution pattern similar to the macrolide antibiotics

Cubensic acid, 3,7,11,15-tetrahydroxy-18-(hydroxymethyl)-2,4,6,10,14,16,20-heptamethyldocosa-4E,8E,12E,16E-tetraenoic acid, has been isolated from the mycelium and culture medium of Xylaria cubensis. Cytochalasin D is an additional metabolite isolated from the culture medium. The structure of cubensic acid has been determined by a combination of spectroscopic and chemical methods. A possible biosynthetic link between cubensic acid and certain macrolide antibiotics is suggested.