Polycyclic polyether antibiotic ionophore, isolated from a strain of Streptomyces albus. Initial description and x-ray structure: M. Allèaume et al., Chem. Commun. 1975, 411. Production from Streptomyces hygroscopicus and use: M. Kuhn, H. D. King, DE 2608337 (1976 to Sandoz), C.A. 86, 28491k (1977). Isoln from S. albus, structure, properties: P. Gachon et al., J. Antibiot. 29, 603 (1976); C. Delhomme et al., ibid. 692. NMR spectrum and solution conformation: N. A. Rodios, M. J. O. Anteunis, Bull. Soc. Chim. Belg. 88, 279 (1979). Revised structure: H. Seto et al., J. Antibiot. 32, 970 (1979). In vitro study: M. Chapel et al., ibid. 740. Effects on cardiovascular function and plasma cation concentration in the dog: N. Moins et al., J. Cardiovasc. Pharmacol. 1, 659 (1979).