Helminthosporium dematioideum

Cytochalasin B Natural product from the fungus Helminthosporium dematioideum (58). Depolymerizes actin hlaments. 

Isoindoles are not known to occur as natural products again, there is a marked contrast with the indoles. However, the cytochalasins, a group of mold metabolites having a marked effect on cell division, contain a highly substituted isoindoline nucleus (3). Cytochalasins A and B (4 and 5) have been obtained from Helminthosporium dematioideum,1 cytochalasins C and D (6 and 7) from Metarrhizium anisopliae,8 and the cytochalasins 8 and 9 from the fungus Phomopsis paspalli found on an Indian millet.9... 

Cytochalasin B (1088) belongs to the [14]cytochalasan group and was isolated from Helminthosporium dematioideum (696) and Phoma S298 (695). Its first total synthesis was accomplished by Stork et al. in 1978 (740). Later, this group published a more simplified synthesis, utilizing an intramolecular Diels-Alder reaction as the key step, forming both perhydroisoindolone and the macrocyclic moiety in a single reaction (741). 

C ochalasins a group of mold metabolites with cytostatic activity. Six chemically similar C. have been isolated from Helminthosporium dematioideum, Memrrhizium anisopliae and Rosellina necatrix. [M.S. Buchanan etal. Phytochemistry 41 (1996) 821-828 M.S.Buchanan etal. Phytochemistry 42 996) 173-176]... 

---