NEW DESTRUXINS FROM THE ENTOMOPATHOGENIC FUNGUS METARHIZIUM-ANISOPLIAE

Four new cyclic depsipeptides have been isolated from the entomopathogenic fungus Metarhizium anisopliae. The chemical structures of destruxins A3 [4] and F [5] and desmethyldestruxins A [6] and C [7] were determined based on nmr and mass spectral data. Destruxin A3 bears an N-methylalanine moiety in place of the usual proline amino acid, while destruxin F contains a new 2,4-dihydroxypentanoic acid subunit. Spectral data for destruxin E diol [8], previously reported as a metabolic product of destruxin E, are also presented.