Biosynthesis of the antibiotic verrucarin E use of [1‐13C]‐, [2‐13C]‐, [1,2‐13C]‐ and [2‐13C, 2‐2H3]‐acetates. Verrucarins and roridins, 37th communication [1]

The origin of the carbon skeleton of verrucarin E (1) from acetate as precursor is confirmed. Incorporation studies with [1,2‐13C]‐acetate have demonstrated that two acetoacetate units couple together as shown in pattern A (Scheme 2) and not as in B. Analysis of the deuterium distribution in both verrucarin E (1) isolated after the incorporation of [2‐13C,2‐2H3]‐acetate and in sodium acetate obtained after Kuhn‐Roth oxidation of the metabolite demonstrated that C(7) is derived from the starter unit of one of the acetoacetate moieties. The deuterium exchange in verrucarin E (1) occurring during fermentation was investigated.