Isochromophilone IX, a Novel GABA-Containing Metabolite Isolated from a Cultured Fungus, Penicillium sp.

Isochromophilone IX, a novel antibiotic active component was isolated from a penicillium species and investigated. Isochromophilone IX displays a specific rotation with the same sign as isochromophilone VI. It was found that isochromophilone represents the first occurrence of an γ-amino butyric acid (GABA) containing metabolite among only four naturally occuring members of this structure class.