Biosynthesis of the polyketide antibiotic ICI139603 in Streptomyces longisporoflavus: assignment of the 13C n.m.r. spectrum by two-dimensional methods, and determination of the origin of the carbon atoms
Abstract
The carbon skeleton of the polyether antibiotic ICI139603 (1) is shown to consist of a polyketide chain, derived from seven acetate units and six propionate units, combined with a C2-unit of unknown origin.