Ganefromycins are antibiotics produced by Streptomyces lydicus sp. tanzanius and were considered for use as performance enhancement agents for livestock. Ganefromycins are one of a small group of kirromycin-like elfamycins which lack the pyridone moiety. A series of ganefromycin antibiotics has been isolated and identified in order to establish their biosynthetic relationships to the previously reported ganefromycin α.