Biosynthetic Studies on Acetosellin and Structure Elucidation of a New Acetosellin Derivative^[*]

Abstract

Natural products from fungi, especially Ascomycota, play a major role in therapy and drug discovery. Fungal strains originating from marine habitats offer a new avenue for finding unusual molecular skeletons. Here, the marine-derived fungus Epicoccum nigrum (strain 749) was found to produce the azaphilonoid compounds acetosellin and 5′,6′-dihydroxyacetosellin. The latter is a new natural product. The biosynthesis of these polyketide-type compounds is intriguing, since two polyketide chains are assembled to the final product. Here we performed ¹³C labeling studies on solid cultures to prove this hypothesis for acetosellin biosynthesis.

Key words

Acetosellin - Epicoccum nigrum - Didymellaceae - azaphilones - polyketides - isotope labeling

^* Dedicated to Prof. Max Wichtl in recognition of his outstanding contribution to pharmacognosy research.

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