Dianemycin is an antibiotic previously reported to affect cation transport and to be effective in treating coccidiosis in chickens. It is isolated from a fermentation broth of Streptomyces hygroscopicus. The compound was found to be primarily active against gram-positive organisms. The chemical properties of dianemycin indicate a close relationship to monensin and other acidiccation complexing compounds. © 1969, JAPAN ANTIBIOTICS RESEARCH ASSOCIATION. All rights reserved.