Biosynthesis of monocerin. Incorporation of 2H-, 13C-, and 18O-labelled acetates by Drechslera ravenelii

Abstract

Incorporation of ²H-, ¹³C-, ¹⁸O-labelled acetates into monocerin (1) by cultures of Drechslera revenelii and analysis of the enriched metabolites by ²H and ¹³C n.m.r. spectroscopy indicate a heptaketide origin; observation of ²H and ¹⁸O isotope shifts in the ¹³C n.m.r. spectrum allows the fate of acetate-drived hydrogen and oxygen on incorporation into monocerin to be followed and conclusions on the mechanism of formation of the fused furobenzopyrone ring system to be drawn.