Biosynthesis of lasalocid. III. Isolation and structure determination of four homologs of lasalocid A.

Four isomeric homologs of lasalocid A have been isolated from cultures of Streptomyces lasaliensis. The homologs each arise by replacement of one of the four propionate derived methyls in lasalocid A by an ethyl group, which results in each homolog molecule containing four C-ethyls.