Abstract
The labeling distribution of averufin and versicolorin B produced from (1‐13C) acetate by Aspergillus versicolor was determined by 13C FT NMR. The results support the polyketide hypothesis for averufin and versicolorin B biogenesis. The pattern of versicolorin B indicates a biogenetic relationship with bisfuranoids, sterigmatocystin and aflatoxins.