Biosynthesis of Cytochalasans. Part 4. The mode of incorporation of common naturally‐occurring carboxylic acids into cytochalasin D

Utilization of sodium [1‐14C]‐, [2–14C]‐, and [1,2‐13C]‐acetates, [1‐14C]‐, [1‐13C]‐, or [2‐14C]‐propionates, [1‐14C]‐or [2‐14C]‐malonates, of [1‐14C]‐ or of [1‐14C]‐myristic acid, or of [1‐14C]‐ and [1‐14C]‐palmitic acid in the biosynthesis of cytochalasin D (1) by Zygosporium masonii was determined by degradation studies or by carbon magnetic resonance spectroscopy. The precursors were incorporated primarily via the acetate‐malonate pathway to generate 1 from nine intact acetate units, eight of which are coupled in a head to tail fashion to form the C16‐polyketide moiety.