Paul H. M. Harrison, Donald W. Hughes and R. William Riddoch
Incorporation of labelled acetates and serine into pramanicin 1 in Stagonospora sp. ATCC 74235 shows that the carbon skeleton of 1 is derived from eight acetate units and a serine residue, implying that the biosynthesis of 1 proceeds via an acyl–tetramic acid intermediate 3.